Patent Publication Number: US-11381615-B2

Title: Sharing social network information

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of and claims the benefit of priority to U.S. application Ser. No. 16/005,066, filed Jun. 11, 2018, which is a continuation of and claims the benefit of priority to U.S. application Ser. No. 14/330,897, filed on Jul. 14, 2014 (now U.S. Pat. No. 10,021,151, issued Jul. 10, 2018), which is a continuation of and claims the benefit of priority to U.S. application Ser. No. 13/967,138, filed Aug. 14, 2013 (now U.S. Pat. No. 8,812,407, issued Aug. 19, 2014), which is a continuation of and claims the benefit of priority to U.S. application Ser. No. 11/079,522, filed Mar. 15, 2005 (now U.S. Pat. No. 8,538,895, issued Sep. 17, 2013), which claims the benefit of priority to U.S. Provisional Application No. 60/552,718, filed Mar. 15, 2004, all of which are hereby incorporated herein by reference in their entirety. 
    
    
     TECHNICAL FIELD 
     This description relates to social networking. 
     BACKGROUND 
     Users of an online service provider who do not have a direct relationship to one another may nevertheless be linked to one another through intermediate entities based on a personal, business or other relationship among the users and the intermediate entities. For example, a user A may have a friend, user B, who also uses that same online service provider and who has a business relationship with user C who also uses the same online service provider. Thus, user A is linked to user C through user B. Such interpersonal interactions or relationships may generally be referred to as a social network. The number of intermediate entities needed to link one entity/user to another may generally be referred to as the degrees of separation between those two entities/users. The social network may be tracked and maintained by the online service provider. The online service provider may generate a social network by observing which users communicate with one another, may build it from user created contact lists or address books, or may ask the users to explicitly create their networks. Social networks may also provide a mechanism for tracking online reputations, and help the users estimate how much to trust one another. 
     SUMMARY 
     In general, social network information may be shared across online service providers. Thus, for instance, one online service provider M that maintains a membership separate from a second online service provider N may nevertheless use the social network maintained by the second online service provider N to tailor content and/or services based on such social network information. 
     Accordingly, in one aspect, social network information from a first online service provider network may be used to modify content or services provided by a second online service provider network. A request for social network information related to a user is sent to a first online service provider network. The social network information related to the user is received and content or services provided by the second online service provider network are modified based on the social network information. 
     Implementations of this aspect may include one or more of the following features. For example, a social network id associated with a username for the user at the first online service provider network may be received and the request for the social network information may include the social network id. The first online service provider network then may determine the social network information related to the user based on this social network id. 
     Similarly, a social network id associated with a username for a second user at the first online service provider may be received as part of a web page provided by the second online service provider network. The social network id may be associated with content in the web page added by the second user or contact information for the second user in the web page. The request for social network information related to the user may include this social network id and a username for the user at the first online service provider network. The first online service provider network then may determine the social network information related to the user based on the social network id and the username of the user. The web page then may be modified based on the social network information. 
     Modifying the web page may include highlighting or changing the position of the content added to the web page by the second user and/or highlighting the contact information for the second user in the web page. The web page may be modified based on the degrees of separation between the user and the second user. For instance, modifying the web page may additionally or alternatively include displaying a visual cue in proximity to the content added to the web page by the second user, or the contact information for the second user in the web page, where the visual cue indicates the number of degrees of separation between the user and the user requesting the web page. Similarly, modifying the web page may alternatively or additionally include changing the position of the content added to the web page by the second user based on the number of degrees of separation between the user and the second user. 
     Reputation information for the second user may be used to modify the web page or other content or services. For instance, the social network information may include a value representing a reputation of the second user among members of a social network including the user. The web page then may be modified, for example, by displaying a visual cue that indicates the value of the reputation for the second user, and/or by changing the position of the content added to the web page by the second user based on the value representing the reputation of the second user. 
     An application, for example, may log into the first online service provider network under a username for the user established at the first online service provider network. The username and an identifier of a server, for example, a web server on the second online service provider network, may be sent to the first online service provider network by the application. The first online service provider network may generate a social network id based on the username and identifier and associates the social network id with the username. The application then may receive the social network id from the first online service provider network and sending the social network id to the server on the second online service provider network. That server then may associate the social network id with an account for the user maintained by the second online service provider. 
     The second online service provider network may maintain a first social network having members including the user. In addition, the social network information received from the first online service provider network may include information regarding members of a second social network that includes the user maintained by the first online service provider network. The members of the first social network may be linked to members of the second social network using the received information regarding members of the first social network. 
     The user may be one, for example, that has requested the content or services provided by the second online service provider network, that has added content to the content or content or services provided by the second online service provider network, or that is a user whose contact information is display in the content or services provided by the second online service provider. 
     In another aspect, a social network server maintained on a online service provider network includes a processor and memory that stores instructions for causing the processor to perform particular operations. As a result of those instructions, the social network server may maintain data indicating one or more social networks for members of the online service provider network. The social network server also may receive a request from a system that is separate from the online service provider network for social network information related to a user. The social network server may determine the social network information related to the user based on the data indicating one or more social network maps and make the determined social network information related to the user accessible to the system that is separate from the online service provider network. 
     Implementations of this aspect may include one or more of the following features. For instance, the system that is separate from the online service provider network may be a client system or a server maintained on a second online service provider network. The social network server may receive, from the system that is separate form the online service provider network, a request for a social network id for the user, generate a social network id for the user, associate the social network id with a username, and send the generated social network id to the system that is separate from the online service provider network. 
     The request for the social network id may include the username and an identification of a server maintained on a second online service provider network. The social network server may generate the social network id based on the username and the identification of the server maintained on the second online service provider network. A request for social network information may include the social network id and the social network id may be used with the data indicating the one or more social networks to determine the social network information. 
     Implementations of the techniques discussed herein may include hardware, a method or process, or computer software on a computer-accessible medium. The details of one or more implementations are set forth in the accompanying drawings and the description below. 
     Other features will be apparent from the description and drawings, and from the claims. 
    
    
     
       DESCRIPTION OF DRAWINGS 
         FIG. 1  is a block diagram of an example of a networked computing environment in which social network information may be shared between online service providers. 
         FIG. 2A  is a flowchart showing a process for determining a user&#39;s social network. 
         FIG. 2B  is a diagram showing an example of a social network list. 
         FIG. 2C  is a diagram showing the social network corresponding to  FIG. 2B  in graphical form. 
         FIGS. 3A-3D , collectively, show the communications and a process that may be performed when a user registers with the web server of  FIG. 1 . 
         FIGS. 4A-4C , collectively, show the communications and process that may be performed when a user retrieves a web page from the web server of  FIG. 1 . 
         FIGS. 5A-6C  show various ways in which a web page may be modified according to social network information. 
         FIGS. 7A and 7B , collectively, show another implementation of the communications and process that may be performed when a user retrieves a web page from the web server of  FIG. 1 . 
         FIGS. 8A-8B , collectively, show another implementation that permits a third party service provider network to maintain a social network for the members of the third online service provider network. 
     
    
    
     DETAILED DESCRIPTION 
     The techniques described in this document may allow social network information to be shared across online service providers. Thus, one online service provider M that maintains a membership separate from a second online service provider N may nevertheless use the social network maintained by the second online service provider N to tailor content and/or services based on such social network information. 
     Generally, the terms “member,” “user,” and “entity” are used interchangeably throughout this description. These terms, however, should not be seen as limited to a person. For example, an organization, such as a corporation, also may use the services provided by an online service provider. Consequently, these terms should be seen as encompassing any entity, actual, legal, or otherwise, that uses a service provider network. 
     In general, entities may be members of an online service provider. The online service provider may maintain a network that provides its members with content and/or one or more communication services, such as chat, instant messaging (IM), e-mail, message boards, and member directories. An entity may use a client application to connect to the online service provider&#39;s network through a global network such as the Internet and to logon to the online service provider&#39;s network by providing a screenname (otherwise referred to as a username) and password that have previously been established with the online service provider. Once the entity is authenticated, the client application may be used by the entity to access the content and communication services provided by the online service provider&#39;s network. The communication services may allow the entity to communicate with other members of the online service provider. The online service provider may provide access to different communications services depending on a level of access granted to the entity and/or based on the client application used by the entity to connect to the online service provider&#39;s network. 
     America Online, Inc. of Dulles, Va. is an example of an online service provider that maintains an online service provider network. America Online® allows entities who subscribe to the America Online® service to connect to the America Online® network using the AOL® client application. These entities are then able to access the proprietary content and communication services provided by the America Online® network. Some of the content and communication services (for example, message boards) are only available to entities who subscribe to the America Online® service and who connect to the America Online® network using the AOL® client application. America Online® also provides instant messaging services to entities, regardless of whether they subscribe to the America Online® service, through the AOL instant messaging (AIM®) client application. An entity may use the AIM® client application to connect to the America Online® network and to use the instant messaging services provided by the America Online® network. More generally, an online service provider network refers to one or more servers that provide some online service or content that users register to use or view. 
     Members of an online service provider may use the online service to maintain user contact lists (e.g., address books or instant messaging contact lists). For example, the AIM® client application allows a user to maintain a contact list (referred to as a Buddy List®) that includes the screennames of the entities to whom the user of the AIM® client desires to send instant messages. 
     Such contact lists may be evaluated to determine the links and the degrees of separation between two entities. For example, entity A may list entity B in entity A&#39;s instant messaging contact list, entity B may list entity C in entity B&#39;s instant messaging contact list, and entity C may list entity D in entity C&#39;s instant messaging contact list. Here, entity B is zero degrees of separation away from A (that is, there are no intermediate nodes between them). Entity C is one degree of separation away from A (they are separated by B). Entity D is two degrees of separation away from A (they are linked via entities B and C). 
     The online service provider may automatically map a first entity&#39;s social network (e.g., the entire social network or up to a designated number of degrees of separation), for example, by evaluating the first entity&#39;s contact list(s) and then successively evaluating the contact list(s) of those entities listed in the first entity&#39;s contact list until the desired number of degrees have been reached or until the entire network has been mapped. For example, entity A may list entities B and C in entity A&#39;s instant messaging contact list. A system may evaluate and determine that entities B and C are so listed and construct a social network map that indicates that entities B and C are linked to entity A. The online service provider may then evaluate the contact lists of entities B and C to determine the entities to which entities B and C are linked. For example, the system may determine that entity B&#39;s instant messaging contact list includes entities D and E, and, consequently, that B is linked to D and E. The system then may refine the social network map to indicate that A is linked directly to B and C and is also linked to D and E through B. The online service provider may additionally or alternatively use other techniques to map a social network. For example, the online service provider may observe which users communicate with one another and/or may ask the users to explicitly create their networks 
     The online service provider may store such information about its members as a social network map, graph, or list. The online service provider may make such social network information available to third party service provider networks (i.e., networks of one or more servers that provide content or services separate from those provided by the online service provider, such as, for example, a web server that is separate from the online service provider&#39;s network). 
     For example, in one implementation, a client system may execute a social network client application that logs into the online service provider&#39;s network. The client system also may execute a web browser that requests a web page from a third party web server. The web page may include social network display code. The social network display code may communicate with the social network client application to request social network information regarding the user of the client system. The social network client application then may use an application programming interface to retrieve social network information for the user of the client system from a social network server on the online service provider network. The social network client application then returns the social network information to the social network display code of the web page, which modifies the web page based on the social network information. Thus, the web page, for example, can be modified based upon the social network relationship between the viewer of the web page and the creator of content in the web page, or the user corresponding to contact information displayed in the web page content. 
     For instance, if the web page provides newsgroup posts, or other content that is added by users of the website, the social network display code may change the order of the posts based on the social network information. The social network display code may, for instance, move posts added by the users in the client system user&#39;s social network to the top of the web page and/or may order them based on the number of degrees of separation between the user who added the post and the client system user. The social network code may alternatively or additionally order the posts based on the posting user&#39;s reputation in the social network of the client system user. Ordering or otherwise changing the position of added content on a web page based on the social network information may, for example, help alleviate problems related to spam content or posts. 
     As another example, a visual cue may be displayed to an entity viewing contact or other information displayed on a web page to represent another entity. The visual cue may directly indicate the degrees of separation between the entity whose contact information is displayed and the entity who is viewing the contact information, may display the pathway between the two, and/or indicate reputation information. For example, if a potential buyer A is reading a post by a seller B (where the post displays seller B&#39;s contact information) on an online auction site (such as the online auction provided by eBay Inc. of San Jose, Calif.), and buyer A is linked to seller B by six degrees of separation, then a visual cue may be displayed in association with seller B&#39;s contact information to indicate to buyer A that entities A and B are linked and separated by six degrees of separation. The visual cue may alternatively or additionally indicate whether members of user A&#39;s social network have marked user B with a positive or negative reputation. 
     Similarly, if a job hunter A is reading a post by an employer B (where the post displays entity B&#39;s contact information) on an employment website, and the job hunter A and employer B are separated by three degrees of separation, a visual cue may indicate that they are separated by three degrees and may additionally or alternatively indicate the path between the two. Providing such information may make a buyer more comfortable buying from the seller, in the case of an online auction, or, in the case of the employment website, may provide information about contacts that can be leveraged by the job hunter to obtain employment with the employer or help the employer determine whether to hire the job seeker. 
       FIG. 1  shows an example of a networked computing environment  100  in which social network information maintained by one online service provider network  120  may be made available to modify the content and/or services provided by a third party online service provider network  110 . Computing environment  100  includes client systems  130   a  and  130   b , service provider network  120 , and a third party service provider network  110  interconnected by a network  150 , such as the Internet. 
     Service provider network  120  may be one like the network provided by America Online®. However, as described above, an online service provider network more generally refers to one or more servers that provide some online service or content that users register to use or view. For example, social network websites, such as the ones provided by Tribe Networks, Inc. of San Francisco, Calif. (located at www.tribe.net) and LinkedIn Corporation of Palo Alto, Calif. (located at www.linkedin.com), may be referred to as online service provider networks. Users register with these websites to obtain a username and password, which the users then use to log onto these websites to access the social network services provided by these websites. As another example, some websites (such as web logs or websites that provide access to newsgroups or forums) allow users to post comments or other content. Before such websites allow users to post content, the websites typically require users to register with the website to obtain credentials, such as a username and password, which the user then uses to log into the website and post content. 
     Service provider network  120  includes a login server  122  that allows a client application to log into service provider network  120  using, for example, a screenname and password. The screenname or username used to log into service provider network  120  is referred to as a service provider username. Once the client application is authenticated and logged into the service provider network by login server  122 , the client application can then access some or all of the services or content provided by service provider network  120 . Service provider network  120  also includes a social network server  124  that determines the social network map(s) or list(s) for members of online service provider network  120  and makes such social network information available for use in modifying a third party provider&#39;s content or services, as described further below. 
     Client systems  130   a  and  130   b  each include, respectively, a web browser  132   a  or  132   b  and a social network client application  134   a  or  134   b . Social network client applications  134   a  and  134   b  log into the service provider network  120  using the client system users&#39; credentials and act as intermediaries to obtain social network information for the client system users, as described further below. The social network client applications  134   a  and  134   b  may be client applications, such as an instant messaging client or an online service provider client like the AOL® client, used by users to access services or content provided by the service provider network  120 . Alternatively, social network client applications  134   a  and  134   b  may be applications that simply act as intermediaries to obtain the social network information. Social network client applications  134   a  and  134   b  may be plug-ins for web browsers  132   a  and  132   b  or other applications, or they may be stand-alone applications or services on client systems  130   a  and  130   b  that may or may not have a user interface. 
     From the standpoint of the online service provider network  120 , network  110  is a third party service provider network (i.e., it provides content and/or services that are not part of service provider network  120 ). In this example, third party service provider network  110  includes a web server  112 . Web server  112  provides web pages, for example, to web browsers  132   a  or  132   b . The web pages provide content or services that can be viewed or used by the users of client systems  130   a  and  130   b . As further described below, while illustrated as including a web server  112 , other implementations of third party service provider network  110  may, in addition or as an alternative to web server  112 , include other types of servers that provide content or services, which may or may not be accessed by client applications other than web browsers  132   a  and  132   b . For example, the third party service provider network  110  may include an e-mail server that provides e-mail service that is accessed by an e-mail client, or an instant messaging server that provides instant messaging service to an instant messaging client. Third party online service provider network  110  may be a network similar to the AOL® network. Third party online service provider  110  may maintain its own social network for the members of third party service provider network  110 . 
     To obtain the content or services from third party service provider network  110 , a user, such as the user of client system  130   a , first registers with web server  112  to establish a username (which is referred to as a third-party username and may be different from the service provider username that is established for service provider network  120 ) and a password. The username and password are then used by the user of client system  130   a  to log onto web server  112  and access the content or services. As described more fully below, in one implementation, the web page that is used by the user of client system  130   a  to register with the web site contains code, such as javascript, that communicates with social network client application  134   a  to obtain a unique id from social network server  124 . The unique id is associated with the service provider username. This unique id is then returned to web server  112  when the user completes the registration and is associated with the user&#39;s account information (including the third-party username) stored by web server  112 . Thus, for this user, web server  112  now stores both a third party username and a unique id provided by social network server  124 . Then, when the user&#39;s third party username or other contact information is displayed in a web page, or content is posted to a web page by the user, the unique id is associated with the contact information or content displayed in the web page. 
     When a second user, such as the user of client system  130   b  using web browser  132   b , subsequently requests a web page that contains the contact information or content created by the user of system  130   a , the associated unique id for the user of system  130   a  is provided along with that contact information and/or content. The web page provided by web server  112  also includes code, such as javascript, that communicates the unique id to social network client application  134   b , which uses the unique id (which is associated with the service provider username of the user of client system  130   a ) and the service provider username of the user of client system  130   b  to obtain social network information from social network server  124  regarding the relationship between the user of client system  130   a  and the user of client system  130   b . The code uses this social network information to modify the display of the web page. For instance, if the user of client system  130   a  is in the social network of the user of client system  130   b , the content posted by the user of client system  130   a  is identified by the associated unique id and may be highlighted or moved to the top of the web page. 
     Each of the client systems  130   a  and  130   b , web server  112 , login server  122 , and social network server  124  may be implemented using, for example, a general-purpose computer capable of responding to and executing instructions in a defined manner, a personal computer, a special-purpose computer, a workstation, a server, a device, a component, or other equipment or some combination thereof capable of responding to and executing instructions. Client systems  130   a  and  130   b , web server  112 , login server  122 , and social network server  124  may receive instructions from, for example, a software application, a program, a piece of code, a device, a computer, a computer system, or a combination thereof, which independently or collectively direct operations, as described herein. The instructions may be embodied permanently or temporarily in any type of machine, component, equipment, storage medium, or propagated signal that is capable of being delivered to client systems  130   a  and  130   b , web server  112 , login server  122 , or social network server  124 . 
     Network  150  may include the Internet, Wide Area Networks (WANs), Local Area Networks (LANs), analog or digital wired and wireless telephone networks (e.g., a Public Switched Telephone Network (PSTN), an Integrated Services Digital Network (ISDN), or a Digital Subscriber Line (xDSL)), or any other wired or wireless network. Network  150  may include multiple networks or subnetworks, each of which may include, for example, a wired or wireless data pathway. 
       FIG. 2A  is a flow chart showing a process  200 , which may be performed, for example, by social network server  124 , to determine a user&#39;s social network. A social network list is maintained for the user ( 202 ). The contacts in one or more of the user&#39;s contact lists (e.g., the user&#39;s instant messaging contact list) are added to the social network list with an indication that the contacts are zero degrees of separation from the user (and, therefore, are directly linked to the user) ( 204 ). 
     Next, the contacts linked to the user through the user&#39;s contacts in the contact list (e.g., up to a desired degree of separation) are identified and added to the social network list. To do so, the contact lists of each contact in the user&#39;s contact list are accessed ( 206 ). The contacts in those lists (i.e., the contacts separated by one degree) then are added to the social network list ( 208 ). If another degree of separation is desired ( 210 ), the degree of separation is incremented ( 212 ) such that the contact lists of the contacts that are separated from the recipient by one degree are accessed ( 206 ) and the contacts in those contact lists are added to the social network list ( 208 ). 
     When a contact is added to the social network list, the contact&#39;s degree of separation from the user also is added and, in addition, the contact that links the user to the added contact may be stored so that an indication can be provided of the path between the user and the added contact. The addition of contacts continues until the desired degree of separation is reached, at which point the social network list is stored for later use ( 214 ). 
     The above process can be modified in a number of ways. For example, at times it may be desirable to have greater assurance that a relationship actually exists between two users before indicating that the two users are directly linked. That is, the before a first user is included in a social network, it may be desirable to have greater assurance that there is a relationship between the first user and a second user which connects the first user to the social network. In particular implementations, such assurance can be obtained by requiring that two entities list each other in their respective contact lists before the entities are considered as having a relationship (and, therefore, are directly linked). In such implementations, an increased likelihood of a relationship between two users is assumed to exist when the two users list each other in their respective contact lists. Thus, for example, before a second user listed in a first user&#39;s contact list is added to the first user&#39;s social network list, the second user&#39;s contact list may be accessed to determine if the first user is listed in the second user&#39;s contact list. If such a bidirectional link exists, then the second user is added to the first user&#39;s social network list. 
     The contact lists used to develop the social network list or otherwise used to map a social network may be stored centrally or in a distributed fashion. For example, the techniques may be applied to an environment in which all of the users&#39; contact lists are stored on a single server (completely centralized), or on a single cluster of servers owned by the service provider (partially centralized/distributed). The contact lists may be stored in a more fully distributed fashion by being stored on each client system (i.e., each user&#39;s contact list is stored on the user&#39;s client system). The contact lists may then be accessed by social network server  124  when social network client application  134   a  or  134   b  is logged into service provider network  122  and temporarily or permanently stored by social network server  124  to develop the social network lists. 
       FIG. 2B  shows an example of a social network list  216 , while  FIG. 2C  shows the corresponding exemplary social network  218  in graphical form. Social network  218  is for an entity designated as User. User is directly linked to User1 and User2 (User may, for example, have User1 and User2 in User&#39;s address book). User1 is linked to User4, while User2 is linked to User3. Consequently, User is linked to User3 (through User2) and User4 (through User1) through one degree of separation. Similarly, User4 is linked to User5 and, consequently, User is linked to User5 (through User4 and User1) through two degrees of separation. 
     Social network list  216  for User contains indications of the entities to which User is linked, the degrees of separation between User and the linked entities, and the entities linking the linked entity to the social network  218 . For instance, an indication of User5 is included, along with an indication that User5 is two degrees of separation from User. There also is an indication that User4 is the entity that links User5 to social network  218  (and, hence, User). Including the entity linking a particular entity to the social network allows the structure of the social network to be determined from the social network list. As an alternative, the entity linking a particular entity to the social network may be excluded. For instance, the social network list may only contain an indication of the entity and its degrees of separation. The social network may alternatively or additionally contain more detailed information about the relationships between the users, such as the degree to which particular users trust or distrust other particular users and/or and indication of the strength of the links between users. 
     While the process described with respect to  FIG. 2A  determines existing social networks, from, for example, contact lists, other ways of forming, determining, or tracking social networks may alternatively or additionally be used. For instance, instead of determining existing social networks, the online service provider may provide tools to users so that they can positively create social networks for use with the social network websites described above. For instance, the online service provider may support an invite-accept model for forming social networks. In an invite-accept model, to become part of a social network, a user receives an invitation from another user to join the social network (i.e., to be linked to the other user). When the user accepts the invitation, he or she is linked to the other user, and hence, the social network. The online service provider then may use social network lists or other techniques to track the links between members of the various social networks. 
     An invite-accept model may be used in conjunction with the techniques described above for determining an existing social network using, for example, contact lists. For instance, the social network list may be constructed using contact lists as described above. Then, as the user receives and accepts invitations to join other social networks, the social network list may be updated to include those directly linked users that the user accepted, and the other users linked at further degrees of separation. 
     In some implementations, the online service provider may observe the communications between users to determine the social network, or to infer the strength of the links between users. For example, the online service provider may observe that two users communicate using instant messaging, and therefore are linked to one another. The online service provider then may observe the frequency of the users&#39; communication to a determine the “strength” of the link between the two. Users&#39; who communicate more frequently, for instance, may have a link with a higher strength than users that communicate less frequently. 
       FIGS. 3A-3C , collectively, show an example of communications ( FIG. 3A ) and a process  300  ( FIGS. 3B and 3C ) that may be performed by web server  112 , web browser  132   a , social network client  134   a , login server  122 , and social network server  124  when the user of client system  130   a  registers with web server  112 . Initially, social network client application  134   a  sends the user&#39;s credentials (e.g., a service provider username and password) to login server  122  and requests that the social network application  134   a  be logged into service provider network  120  ( 302 ). For example, if the social network client application  134   a  is an instant messaging application, the user may invoke the instant messaging application and provide the service provider username and password to the instant messaging application using an interface of the instant messaging application. This may be performed by the user in anticipation of registering with web server  112  or may be performed simply to use the instant messaging application to engage in instant messaging with other users. As described above, social network application  134   a  may, alternatively or additionally, be implemented as a plug-in for web browser  132   a . In such a case, social network client application  134   a  may be invoked when web browser  132   a  is invoked. 
     Login server  122  then authenticates the credentials and, assuming the credentials are authentic, logs social network client application  134   a  into service provider network  120  ( 304 ). Once login server  122  logs in social network client application  134   a , login server  122  sends a response back to social network client application  134   a  indicating that the login was successful ( 306 ). 
     Web browser  132   a  then requests the registration page (an example is shown in  FIG. 5A ) from web server  112  ( 308 ). Web server  112  returns the registration web page  350  (which includes social network registration code) to web browser  132   a  ( 310 ), which renders the registration web page ( 312 ). 
     Referring to  FIG. 3D , web page  350  may include a mechanism, such as a checkbox  352 , that allows the user of client system  130   a  to indicate that his or her social network information maintained by service provider network  120  should be associated with the account on web server  112 . Web page  350  also includes text fields  354  and  356  that allow the user to enter his or her name, text boxes  358  and  360  that allow the user to establish a third party username and password by entering them into text boxes  358  and  360 , respectively, and a text box  362  that allows the user to enter his or her e-mail address. Once the user has entered this information, he or she may select “submit” button  364  to complete registration by sending this registration information to web server  112 . 
     The social network registration code is executed when the user indicates that the social network information should be associated with the account on web server  112 , for example, by selecting checkbox  352 . The social network registration code may be implemented in, for example, javascript or another scripting language supported by web browser  132   b , or may be implemented, for example, as an ActiveX control or Java applet. 
     Referring again to  FIGS. 3A-3C , when executed, the social network registration code passes a request for a social network id to social network client application  134   a  ( 314 ). The social network registration code may pass the request, for example, using an interprocess communication protocol. Alternatively, social network client application  134   b  may implement a server, such as a web server, that listens at a specified port on client system  130   b . In such a case, the social network registration code may pass the request to the server by sending a hypertext transfer protocol (HTTP) or other protocol request to the server at the open port. 
     The request passed to social network client application  134   a  may include a unique identifier for web server  112 , such as the uniform resource locator (URL) for web server  112 . Social network client application  134   a  then requests a social network id from social network server  124  ( 316 ). To do so, social network client application  134   a  may send to social network server  124  the unique identifier for web server  112  and the service provider username used by social network client application  124  to log onto service provider network  120 . Social network client application  124  may do so, for example, by using an application programming interface (API) provided for social network server  124 . The API may implement a function similar to the following: getSocialNetworkID (current_username, URL), where current_username is equal to the service provider username used by social network client application  134   a  to log into service provider network  120  and URL is equal to the unique identifier of web server  112 . Social network client application  134   a  may call such a function to obtain the social network id from social network server  124 . 
     Social network server  124  then generates a unique social network id and associates that social network id with the service provider username used by social network client application  134   a  to log onto service provider network  120  ( 318 ). Social network server  124  may generate a social network id that is unique from other social network ids, and is specific to web server  112 . For example, social network server  124  may apply a hash function that generates unique ids to a concatenation of the web server URL and service provider username. Accordingly, if the user of client system  130   a  visits another web server and associates the social network information with the different web server, a different, unique social network id will be created specifically for that different server and associated with the service provider username. In other words, a particular service provider username may have different social network ids for each different website. This process of having the browser connect from the client via the social network application, may prevent the third party service provider from being able to directly determine the service provider username and may thereby afford the user a measure of security and anonymity. The inclusion of a site identifier to generate the unique social network id may prevent other web sites from copying data in an attempt to spoof the social network. 
     After generating the social network id, social network server  124  returns the social network id to social network client application  134   a  ( 320 ), which in turn returns the social network id to the social network registration code ( 322 ). The social network registration code may, for example, store the social network id in a variable that is returned to web server  112 . 
     As the social network registration code obtains the social network id, the user may enter a username and password for web server  112  (that is, a third party username and password), and provide other registration information, by entering such information into text boxes  354 ,  356 , and  362  on web page  350 . The user then may submit this information and complete registration, for example, by selecting submit button  364  on registration web page  350 . After the user selects the submit button, web browser  132   a  submits the information entered into text boxes  354 - 362 , along with the social network id, to web server  112  ( 324 ). 
     Web server  112  then generates an account for the user and stores the registration information in the account, along with the social network id ( 326 ). While not shown in  FIGS. 3A-3C , when a user subsequently wishes to access content or services provided by web server  112 , a login web page is obtained from web server  112  and the user enters his or her third party username and password into the login web page and submits these credentials to web server  112 . Once logged in, the user can access the content or services provided by web server  112 , such as adding content to web pages or communicating with other users of web server  112 . 
       FIGS. 4A-4C , collectively, show an example of communications and a process  400  that may be performed by web server  112 , web browser  132   b , social network client  134   b , login server  122 , and social network server  124  when the user of client system  130   b  retrieves a web page from web server  112 . As with process  300 , in process  400  social network client application  134   b  logs into service provider network  120 . To do so, social network client application  134   b  sends the credentials (e.g., a service provider username and password) for the user of client system  130   b  to login server  122  and requests that the social network application  134   b  be logged into service provider network  120  ( 402 ). Login server  122  then authenticates the credentials and, assuming the credentials are authentic, logs social network client application  134   b  into service provider network  120  ( 404 ) and sends a response back to social network client application  134   b  indicating that the login was successful ( 406 ). 
     Web browser  132   b  then requests a web page (examples are shown in  FIGS. 6A-7C ) from web server  112  ( 408 ), and web server  112  returns the web page  450  ( 410 ). The web page retrieved may include the username or other contact information for, and/or content added by users, such as the user of client system  132   a . For users, such as the user of client system  132   a , that have associated their social network information with their account for web server  112 , the content added by these users, or the contact information for these users, has the user&#39;s corresponding social network id associated with the content or contact information. 
     Web pages are typically written in the hypertext markup language (HTML) or other markup language such as the extensible markup language (XML). In such languages, tags are used to define how a web browser should display the content of the web page. One method of associating the social network id with content or contact information is to set the “id” attribute of a tag surrounding the added content or contact information equal to the users social network id. 
     The following is a simple example of a portion of the HTML of a web page using such a technique to associate a social network id with the content added by the corresponding user: 
     &lt;p id=235678&gt;Hello Everyone!&lt;p&gt; 
     In this example, the “id” attribute of the &lt;p&gt; tag (which represents a paragraph) is set equal to a social network id of “235678,” which, for example, may be the social network id for the user of client system  132   a.    
     In addition to having social network ids associated with added content or contact information, the retrieved web page includes social network display code, which, similarly to the social network registration code, may be implemented, for example, in javascript or another scripting language, or may be implemented, for example as an ActiveX control or Java applet. After web browser  132   b  receives the web page, web browser  132   b  begins rendering the web page ( 412 ), which executes the social network display code. For example, if javascript is used, then the social network display code may be executed in response to the “onLoad” event. 
     When executed, the social network registration code passes a request for social network information to social network client application  134   b  ( 414 ). As with the social network registration code, the social network display code may pass the request, for example, using an interprocess communication protocol or by sending a request to server implemented by the social network client application  134   b.    
     The request passed to social network client application  134   a  includes one or more of the social network ids, and may specify a type of social network information requested, depending on how the web page is to be modified. For example, the social network display code may highlight content added by users within a certain number of degrees of separation, or may modify the page to reflect the degrees of separation. In such a case, only the degrees information needs to be request. Alternatively, or additionally, for example, the social network display code may modify the web page to display the pathway between two users. In such a case, the social network display code may request the path information (i.e., which users connect the two users and how). As another example, the social network display code may highlight contact information for, and/or content created by, users with particularly good reputations. The social network display code may alternatively or additionally hide contact information for, or content created by, users with bad reputations. In another scenario, the social network display code may reorder the content such that content created by users with good reputations is shown first. In such instances, the social network display code may request the reputation information. 
     Social network client application  134   a  then requests the social network information from social network server  124  ( 416 ). To do so, social network client application  134   a  may send social network server  124  the social network ids provided by the social network display code, the service provider username used by social network client application  124  to log onto service provider network  120 , and other information as necessary. Social network client application  124  may do so, for example, by using an API provided for social network server  124 . Depending on the information requested by the social network display code, different types of information may be accessed through the API. For example, the API may have a number of different functions that can be called based on the information requested by the social network display code. For example, the API may have the functions similar to the following:
         isDegrees (current_username, site_id, sn_id, degrees), where current_username is a service provider username, site_id uniquely identifies the third party service, sn_id is an array of one or more social network ids, and degrees is a number. This function may return a boolean for each social network id indicating whether the service provider username associated with the social network id and the “current_username” are within the number of degrees of separation specified by “degrees.”   getPath (current_username, site_id, sn_id), where current_username is a service provider username, site_id uniquely identifies the third party service, and sn_id is an array of one or more social network ids. This function may return for each social network id an object containing the path between the service provider username associated with the social network id and the “current_username.”   getDegrees (current_username, site_id, sn_id), where current_username is a service provider username, site_id uniquely identifies the third party service, and sn_id is an array of one or more social network ids. This function may return for each social network id a number indicating the degrees of separation between the service provider username associated with the social network id and the “current_username.”       

     Thus, depending on the information needed, social client network application  134   b  may call the appropriate function and pass the service provider username used by social network application  134   b  to log into the service provider network through the current_username variable, pass the social network ids provided to social network client application  134   b  by social network display code through the variable sn_id equal, and, if needed, pass a number of degrees of separation requested by social network display code through the variable degrees. The unique site_id identifier may also be passed to social network server  124  in order to verify that the social network ids were actually registered with the site for which the social network code and/or social network client application is requesting information. 
     Social network server  124  then uses the social network ids to determine the corresponding service provider usernames. Using the determined usernames and the username provided by social network client application  134   b , social network server  124  then determines the requested social network information using, for example, a social network list, such as the one shown in  FIG. 2B  ( 418 ). 
     Social network server  124  then returns the requested social network information to social network client application  134   b  ( 420 ), which in turn returns the requested social network information to the social network display code ( 422 ). Based on the requested social network information, the social network client code modifies the display of the web page. To do so, for example, the social network code may access the document object model (DOM) of the web page and modify nodes of the DOM as appropriate to modify the web page based on the social network information. For example, when the “id” attribute in a tag surrounding content added by a user is set to the user&#39;s social network id, the social network display code may access the corresponding node using the social network id. After accessing the node, for instance, the social network display code may move the node (thereby changing where the content is displayed on the page). The social network display code may add highlighting or perform other style changes to the node, or a child node that represents the added content. 
     There are a number of ways a page can be modified based on social network information. For example, as described above, the position of content added to a web page by users may be changed based on the social network information. Thus, for instance, content added by users not in the viewing user&#39;s social network may be hidden, or moved towards the bottom of the web page. The content added by users may be ordered on the web page according to the number of degrees of separation between the users and the viewing user, by the social network reputations for the content authors, or based on the link strength between relationships in the social network. 
     As another example, the added content or contact information of a user may be modified to reflect the social network information. For example, a visual cue may be associated with the content or contact information to indicate the degrees of separation between the viewing user and the author of the content or the user corresponding to the contact information, and/or the reputation of the content author. For instance, an icon may be displayed next to the contact information or content, or a color may be associated with the contact information or content. The color may be associated, for example, by highlighting or changing the color of the contact information (e.g., the second user&#39;s screen name or e-mail address) or added content. The color may directly indicate the degrees of separation between the users by corresponding to a particular number of degrees. For instance, green may correspond to one degree of separation, while red corresponds to two degrees of separation. In another case, the color of the icon may represent the reputation of the user to which it is linked. As yet another example, the pathway between the viewing user and the author of the added content or the user corresponding to displayed contact information may be displayed in the web page, or may be displayed in a pop-up web page that is invoked if the contact information or content is selected by the viewing user. Thus, the social network display code may modify the web page to provide a pop-up that displays the pathway when the contact information or content is selected. 
     As an example of one way in which the social network display code may modify web page  450 ,  FIG. 5A  shows web page  450  rendered in browser  132   b  without being modified, while  FIG. 5B  shows web page  450  modified according to social networking information. In this example, web page  450  provides access to newsgroups, such as the USENET newsgroups. 
     Referring to  FIG. 5A , web page  450  includes a section  510  that includes a link  512  and links  514 . Selecting link  512  retrieves a web page that allows the user to browse the various newsgroups and select one newsgroup to view the posts to that newsgroup. Links  514  reflect recently viewed newsgroups and, when one of links  514  is selected, the corresponding newsgroup is displayed. 
     Web page  450  also includes a section  520  that displays headers  524  for posts to the currently selected newsgroup. A title  522  displays the name of the currently selected newsgroup. 
     There are three headers  524  shown, header  524   a ,  524   b , and  524   c . Header  524   a  is listed first (at the top), header  524   b  is listed second, and header  524  is listed last (at the bottom). Headers  524  display some information about each post, such as, for example, a title for the post, the username or e-mail address of the user who added the post, and a brief synopsis of the post. Headers  524  also include a link to view the entire post. For example, header  524   a  displays the title “Hello yall, check this out,” the e-mail address dl1618@hotmail.com, the synopsis that starts with “Free quick easy money period,” and a hyperlink “Read More” that allows the user to view the entire post. 
       FIG. 5B  shows a version of web page  450  that is modified by the social network display code to reorder the headers  524  based on the degrees of separation between the user viewing headers  524  (for example, the user of client system  130   b ) and the users who added the posts corresponding to headers  524 . In this example, the user of client system  130   b  is connected to the user who added the post corresponding to header  524   b  and the user who added the post corresponding to header  524   c , but is not connected to the user who added the post corresponding to header  524   c . In addition, the user of client system  130   b  is connected to the user who added the post corresponding to header  524   b  by fewer degrees of separation than the user that added the post corresponding to header  524   c.    
     Accordingly, the social network display code, after receiving the degrees of separation information, has modified the order in which headers  524  are displayed. Social network display code has modified headers  524  such that header  524   b  is displayed first (at the top) because the fewest number of degrees of separation exist between the user of client system  130   b  and the user that added the post corresponding to header  524   b . In addition, header  524   c  is listed second and header  524   a  is listed last because the user of client system  130   b  is not connected to the user that added the post corresponding to header  524   a.    
     As other examples,  FIGS. 6A-6C  show various ways in which a web page  600  may be modified according to social networking information. In these examples, web page  600  provides access to an auction on an auction web site. 
     Referring to  FIG. 6A , web page  600  includes a title  610  that describes the item being auctioned. Web page  600  also includes a section  620  that provides information about the auction, such as the starting bid, the time left until the auction is over, the location of the item being auctioned, where the seller is willing to ship the item, and the shipping cost of the item being auctioned. A button  622  allows a user to place a bid on the item being auctioned. 
     A section  630  includes information about the seller of the item. Section  630  includes hyperlinks  632  that allow the user to access to access feedback comments added by other users who have bought items from the seller, to send a question to the seller, and to view other items for sale or auction by the seller. Section  630  also displays the date  634  when the seller became a member of the auction site and a feedback rating  636 , which may be based on negative or positive comments the seller has received from other users. 
     Contact information  638  for the seller is also displayed in section  630 . In this case, the contact information is the third party username for the seller (the example “Eric” being shown). The social network display code has modified web page  600  to display an icon  638   a  next to contact information  638 . Icon  638   a  displays the number of degrees of separation between the user viewing web page  450  (for example, the user of client system  130   b ) and the seller. 
     Referring to  FIG. 6B , in one implementation, web page  600  also is modified so that a user is able to invoke a pop-up window  640  that displays the pathway  642  between the user and the seller. Window  640  can be invoked, for example, by selecting icon  638   a . Window  640  represents the user viewing web page as “You,” and represents the intermediate entities and the seller by their respective service provider usernames. In the example shown, the user (indicated by “You”) is linked to User2, who in turn is linked to the seller, whose service provider username is User3. 
     For privacy concerns, some users may not want to have their information displayed in a pathway, such as the pathway  642 . To accommodate such concerns, some implementations may permit users to opt out of having their information displayed in a pathway that connects a user to a linked user. For a user who has opted out of having information shown, pathway  642  may be modified, for example, by changing the user&#39;s screenname to “unknown,” for example. 
     Referring to  FIG. 6C , in another implementation, web page  600  also is modified so that a user is able to invoke a pop-up window  650  that displays profile information for the seller stored on service provider network  120 . Social network display code may request such profile information from social network client application  134   b , which in turn retrieves such information from social network server  124  or another server. Window  650  can be invoked, for example, by selecting icon  638   a . Window  650  includes a section  652  that presents profile information for the seller stored by service provider network  120 , such as the seller&#39;s name, job title, addresses, phone numbers, and interests. 
     Using an architecture such as the one shown in  FIGS. 3A and 4A , where social network client application  134   b  executing on a client system  130   b  retrieves social network information and the content is modified based on the social network information using social network display code in the web page, may provide improved scalability as compared to an architecture in which web server  112  retrieves social network information, such as the one describe below with respect to  FIG. 7A . The improved scalability may allow web server  112  to handle larger numbers of users at the same computing power of web server  112 . Architectures in which web server  112  or another server on third party service provider network  110  retrieves social network information may, however, be more desirable depending on how social network information is used to modify the content or services of the third party service provider network  110 . 
     Referring to  FIGS. 7A and 7B , in another implementation, web server  112  may request the social network information from social network server  122  and modify the web page based on this social network information before the web page is sent to web browser  132   b . If the user who is requesting the web page, such as the user of client system  130   b , has also registered with web server  112  using the process and communications described with respect to  FIGS. 3A-3D , then web server  112  may also be storing a social network id for that user. That is, for example, web server  112  may have stored a social network id for the user of client system  130   a  and a social network id for the user of client system  130   b . The user of client system  130   b  may log onto web server  112  before requesting a web page, so as to thereby allow web server  112  to identify and access the social network id of the user of client system  130   b . Accordingly, if the user of client system  130   b  uses web browser  132   b  to request a web page that contains content added by, or contact information for, the user of client system  132   a , web server  112  may access the social network ids for both of these users, and use the social network ids to request social network information from social network server  122 . Web server  112  then may modify the web page based on this social network information and send the modified web page to web browser  132   b.    
     More particularly,  FIGS. 7A and 7B , collectively, show examples of communications and a process  700  for such an implementation. The user may use web browser  132   b  to log onto web server  112  and request a web page that contains content added by, or contact information for, other users, such as the user of client system  132   a  ( 702 ). The content added by the users, or the contact information for the users, may be associated with the social network id of the corresponding user. The social network ids may be associated with the content or contact information by being embedded in the HTML of the web page, for example, by using the “id” attribute as described above. Alternatively, web server  112  may use a program, such as a common gateway interface (CGI) script, to generate the HTML or other markup for the web page, and the other components the web page (e.g., scripts). In such a situation, the content or contact information may be stored in a database or other storage until the web page is requested. When the web page is requested, the CGI script accesses the content or contact information to dynamically generate the web page. In such a situation, the social network id may be associated with the content or contact information in the database or other storage. 
     Web server  112  then requests the social network information from social network server  124  ( 704 ). For example, the request for the web page may be directed to a program, such as a CGI script, executing on web server  112 . When the request for the web page is received, the CGI script then accesses the social network id of the requesting user and the social network ids associated with the content or contact information to be included in the web page (for example, by accessing the HTML or other mark-up of the web page or by accessing a database that stores the content or contact information). The CGI script then may send to social network server  124  the social network ids, and other information as necessary. The CGI script may do so, for example, by using an API provided for social network server  124 . Functions similar to those described above may be implemented by the API. For example, the API may have the functions similar to the following:
         isDegrees (user_sn_id, site_id, sn_id, degrees), where user_sn_id is the social network id for the user requesting the web page, site_id uniquely identifies the third party service, sn_id is an array of one or more social network ids associated with the content or contact information, and degrees is a number. This function may return a boolean for each social network id in the sn_id array indicating whether the social network id in the array and the social network id of the user requesting the web page are within the number of degrees of separation specified by “degrees.”   getPath (user_sn_id, site_id, sn_id), where user_sn_id is the social network id for the user requesting the web page, site_id uniquely identifies the third party service, and sn_id is an array of one or more social network ids. This function may return for each social network id in the array an object containing the path between the social network id in the array and the social network id of the user requesting the web page.   getDegrees (user_sn_id, site_id, sn_id), where user_sn_id is the social network id for the user requesting the web page, site_id uniquely identifies the third party service, and sn_id is an array of one or more social network ids. This function may return for each social network id in the array a number indicating the degrees of separation between the social network id in the array and the social network id of the requesting user.       

     Social network server  124  then uses the social network ids to determine the corresponding service provider usernames. Using the usernames, social network server  124  then determines the requested social network information using, for example, a social network list, such as the one shown in  FIG. 2B  ( 706 ), and returns the requested social network information to web server  112  (e.g., to the CGI script executing on web server  112 , if implemented) ( 708 ). 
     Web server  112  then modifies the web page based on the social network information ( 710 ). For example, if a program such as a CGI script is implemented, the CGI script may modify the HTML or other markup of the web page based on the social network information. Alternatively, the CGI script may dynamically generate the HTML or other markup for the web page and other components of the web page, modifying the web page based on the social network information as the web page is generated. The web page may be modified in the ways described above, such as reordering, highlighting, or deleting content or contact information, inserting social network information into the web page, or making social network information or other information available in, for example, a pop-up window. Web server  112  then sends the modified web page  750  to web browser  132   b  ( 712 ), which then renders the web page  750  ( 714 ). 
     Referring to  FIGS. 8A and 8B , in other implementations, third party service provider network  110  may maintain a social network for the members of third party online service provider network  110  (referred to as a third party social network), and may use the third party social network in providing services or content to the members of online service provider network  110 . In addition, the third party service provider network  110  may modify these services or content based on the social network maintained by online service provider network  120 . That is, a user may be a member of both the third party social network maintained by third party online service provider  110  and a member of the social network maintained by online service provider  120 . 
     In general, if the user of third party network  110 , such as the user of client system  130   b , has registered using the process and communications described with respect to  FIGS. 3A-3D , then third party online service provider network  110  may also be storing a social network id for that user. The third party online service provider network  110  may use the social network id to retrieve social network information related to the user from the social network maintained by the service provider network  120 . This retrieved social network information may be used to modify the content or services provided by the third party service provider network  110  based on the third party social network. 
     In particular, with respect to  FIG. 8A , the third party online service provider uses social network information to inform filtering of e-mail. In this implementation, third party online service provider network  110  includes an e-mail server  112   a  in place of (or in addition to) web server  112 . Third party online service provider network  110  also includes asocial network server  114  (referred to as a third party social network sever), which may be similar to social network server  122 , except that third party social network server  114  maintains social network information for the members of third party online service provider network  110 . The user of client system  130   b  may use an e-mail client  130   b - 1  instead of web browser  132   b  to access e-mail from e-mail server  112   a.    
     Third party online service provider network  110  may use social network information, of example, to create a trusted list of senders for a user, such as the user of client system  130   b , and use the trusted list to inform filtering of the e-mails sent to the user. For example, the e-mail server may use the trusted list as a white list to allow e-mail from e-mail addresses on the trusted list, while blocking e-mail from e-mail addresses not on the trusted list. Methods of filtering e-mail or other communications based on trusted lists developed from social network information is further described in U.S. application Ser. No. 10/746,232, filed Dec. 29, 2003, and titled “Degrees of Separation for Handling Communications,” which is incorporated herein in its entirety for all purposes. 
       FIGS. 8A and 8B  show examples of communications and a process  800  for such an implementation. E-mail server  112   a  may create the trusted list for a user, such as the user of client system  130   b , by first requesting, from social network server  114 , the e-mail addresses for other users within a certain number of degrees of separation from the user ( 802 ). Social network server  114  then requests the social network information from social network server  124  ( 804 ). To do so, social network server  114  may access the social network id of the user and send to social network server  124  the social network id, and other information as necessary. Social network server  114  may do so, for example, by using an API provided for social network server  124 . For example, the API may have a function similar to the following: getEmails (sn_id, degrees), where sn_id is the social network id for the user and degrees is the number of degrees of separation requested by e-mail server  112   a . This function may return an array of the e-mail addresses for users within the specified degrees of separation. 
     Social network server  124  uses the social network id to determine the associated username. The associated username is then used to determine the users within the specified degrees of separation, and their corresponding e-mail addresses ( 806 ). Once determined, social network server  124  returns the e-mail addresses to social network server  114  ( 808 ). 
     Social network server  114  returns to e-mail sever  112   a  the e-mail addresses retrieved from social network server  124 , in addition to the e-mail addresses of users within the third party social network that are within the specified degrees of separation ( 810 ). E-mail server  112   a  uses the e-mail addresses to generate the trusted list and to filter or otherwise modify the e-mails received for the user accordingly ( 812 ). When e-mail client application  132   b - 1  subsequently requests the e-mails for the user of client system  130   b  ( 814 ), e-mail server  816  provides the filtered or otherwise modified e-mails to e-mail client application  132   b - 1 , which displays them to the user ( 816 ). 
     A number of other implementations are possible depending on the content or services provided by third party service provider  110 , and the social network information made available through the API for social network server  122 . For example, in an implementation similar to that shown in  FIG. 8A , the third party service provider network may provide general social network services, such as those provided by Friendster, Inc. of Silicon Valley, Calif. (located at www.friendster.com). Such services allow a user to view profiles and access content maintained by members of the user&#39;s social network, in addition to allowing the user to communicate with members of the user&#39;s social network. Through the API provided for social network server  122 , information may be retrieved for the members in the user&#39;s social network maintained by online service provider  120 , and the information may be used to link those members, through the user, to the members in the user&#39;s social network maintained by social network server  122 . Such information may include profiles or content maintained by these members and/or contact information for these members. This may allow members of the user&#39;s third party social network maintained by third party service provider  110  to be connected, through the user, to members of the user&#39;s social network maintained by online service provider  120 , and may allow members of the third party social network to navigate to, interact with, or view information about the members of the user&#39;s social network maintained by online service provider  120 , and may provide mechanisms for the members of the user&#39;s third party social network to communicate with the members of the user&#39;s social network maintained by online service provider  120 . For example, a member of the user&#39;s third party social network may be able to access profile information for a member of the user&#39;s social network maintained by service provider  120 . The profile information may contain contact information for the member, such as an e-mail address for an e-mail account provided by service provider  120 . 
     Instead of showing the member&#39;s contact information, the third party service provider network  110  may provide a form, such as a web form, for the member of the third party social network to enter and send messages to the other member. Once the member submits the message, the third party service provider network  110  may send the message using, for example, the other member&#39;s e-mail address for an e-mail account provided by service provider  120 . 
     In addition, one user in a social network may try to access content maintained by another user in the social network. For example, a first user may attempt to access a calendar maintained by a second user. Whether the user can access the calendar, or what information is shown on the calendar, may be based on the types of relationships connecting the first user to the second user (e.g., whether the relationships are family relationships, friend relationships, or business relationships). Such techniques are more fully described in U.S. application Ser. No. 11/079,524, filed concurrently with this application on Mar. 15, 2005, titled “Social Networking Permissions,” now U.S. Pat. No. 8,595,146, issued Nov. 26, 2013, and incorporated herein in its entirety for all purposes. The third party online service provider network  110  may communicate with social network server  122  to implement such permissions across the service provider boundaries. For example, a member of the third party social network may be connected to a member of the social network maintained by online service provider network  120  through a user that is a member of both networks. The member of the third party social network may use the services provided by third party service provider to attempt to access content maintained by the member of the online service provider  120 . Third party social network server  114  and social network server  114  may communicate to determine the type of access based on the types of relationships connecting the members, and to provide the appropriate type of access to the requested content. 
     The techniques described above are not limited to any particular hardware or software configuration. Rather, they may be implemented using hardware, software, or a combination of both. The methods and processes described may be implemented as computer programs that are executed on programmable computers comprising at least one processor and at least one data storage system. The programs may be implemented in a high-level programming language and may also be implemented in assembly or other lower level languages, if desired. 
     Any such program will typically be stored on a computer-usable storage medium or device (e.g., CD-Rom, RAM, or magnetic disk). When read into the processor of the computer and executed, the instructions of the program cause the programmable computer to carry out the various operations described above. 
     Furthermore, elements of different implementations may be combined, deleted, added, supplemented or modified to yield further implementations. In addition, actions or communications do not necessarily need to occur in the order in which they are depicted. Accordingly, other implementations are within the scope of the following claims.