Abstract:
A system and method are disclosed for protecting e-mail sender identity by redirecting e-mail messages to an e-mail forwarding server via use of customized recipient e-mail addresses. An e-mail message is sent from a user&#39;s actual e-mail account to a customized recipient e-mail address. Because an e-mail forwarding server of the present invention is the Mail Exchange (MX) authority for the domain of the customized recipient e-mail address, the e-mail message is sent to the e-mail forwarding server. The e-mail forwarding server contains a database that stores users&#39; actual e-mail addresses and their associated alias e-mail addresses. When the message is received by the e-mail forwarding server, it parses the message recipient&#39;s e-mail address to obtain the intended recipient&#39;s e-mail address, replaces the message sender&#39;s actual e-mail address with its associated alias e-mail address, and delivers the message to the original intended recipient. To the recipient the message appears to be sent directly from the sender&#39;s alias e-mail address. Therefore the sender&#39;s actual e-mail identity is not exposed to the recipient. When the e-mail forwarding server receives an e-mail message sent or replied to the user&#39;s alias e-mail address, it automatically forwards the message to the user&#39;s actual e-mail address.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit of provisional patent application Ser. No. 60/823,145, filed Aug. 22, 2006 by the present inventor. 
     
     FEDERALLY SPONSORED RESEARCH 
       [0002]    Not Applicable 
       SEQUENCE LISTING OR PROGRAM 
       [0003]    Not Applicable 
       BACKGROUND 
       [0004]    1. Field of the Invention 
         [0005]    The present invention relates to a system and method for protecting e-mail sender identity, and more specifically to a system and method utilizing customized recipient e-mail addresses to redirect e-mail messages to an e-mail forwarding server to protect sender&#39;s actual e-mail address and other identifying information from being exposed on a communications network. 
         [0006]    2. Prior Art 
         [0007]    E-mail is an essential communications tool for business and individuals. However exposing actual e-mail identity on the Internet is becoming a problem because actual e-mail identity may contain personal information, such as senders&#39; e-mail addresses, company or organization names, network usernames, and Internet Service Provider (ISP) names. E-mail address itself could also be sensitive personal information since it may associate with online banking or e-commerce user IDs. As incidences of online identity theft have steadily climbed in recent years, there is always a risk that someone could glean enough personal information to usurp people&#39;s identity. Therefore the actual e-mail identity should be protected just like other personal identifying information, only being given out to trusted parties. 
         [0008]    Spam is another reason why actual e-mail identity should NOT be exposed on the Internet. For most Internet users getting spam messages each and every day is a fact of life. Even with various state and federal laws and spam filtering software, this barrage seems to be never ending. One of the best strategies to avoid spam is to keep the actual e-mail addresses private and not let spammers know they even exist. But this is a difficult task to accomplish. Every time Internet users give their actual e-mail addresses to an online vendor, send a message to a mailing list, or join a web forum, they are exposing their actual e-mail addresses. Therefore protecting the actual e-mail addresses is easier said than done. 
         [0009]    One approach to solving half of this problem is using e-mail forwarding services. Current e-mail forwarding services are able to forward e-mail messages received from one e-mail address to anther e-mail address. Therefore users&#39; actual e-mail accounts can receive e-mail messages which are sent to the e-mail addresses of the e-mail forwarding service. It helps to keep actual e-mail addresses private. But this method only works for receiving e-mail messages. It cannot protect the actual e-mail addresses from being exposed on the Internet if they want to send e-mail messages directly from their actual e-mail accounts. 
         [0010]    Another approach to protecting the actual e-mail addresses from identity theft and spam is using separate e-mail accounts. For example, two e-mail accounts can be created: One for friends and family only, and another for others. If the e-mail address for others starts getting spammed, it can be just abandoned, without having to create a new e-mail address for friends and family again. However this method is inconvenient for those who need to switch back and forth between different e-mail addresses frequently. Usually it requires users to enter their user names and passwords to log on different e-mail accounts if they want to send e-mail messages with a different e-mail address. 
         [0011]    Yet another approach to sending or receiving e-mail messages with a different e-mail address is using “Send As” feature in some e-mail systems. The “Send As” feature allows a user to send e-mail messages as if from another e-mail address or e-mail account. But the “Send As” feature has many limitations: First not every e-mail system provides the “Send As” feature and e-mail users have no choice if their e-mail system doesn&#39;t offer this feature. Second the “Send As” feature may require a system administrator to setup a separate e-mail address and grant proper permissions for a user to use it. Third it may also require e-mail users to use some specific e-mail client software or devices (e.g., Microsoft Outlook) and many mobile devices or e-mail client software either do not support the “Send As” feature or can not easily switch back and forth between different e-mail addresses or e-mail accounts. Fourth the “Send As” feature could possibly cause the sender&#39;s actual e-mail address, e-mail domain name, and computer IP address being revealed. Because some e-mail systems store sender&#39;s actual e-mail address and computer IP address in the message headers or use the same e-mail servers delivering both e-mail messages. Fifth the “Send As” feature could also cause e-mail messages being marked as spam if the messages are sent from the e-mail systems which are not legitimate mail sources for the “Send As” e-mail address domain. 
         [0012]    Apparently, there is a clear need for a convenient, reliable and effective manner of protecting e-mail identity. Embodiments of the present invention provide a novel system and method for protecting users&#39; actual e-mail identities from being exposed on the Internet. 
       SUMMARY 
       [0013]    The present invention is a system and method for protecting the identity of an e-mail sender via use of customized recipient e-mail addresses. The system and method comprise the steps of: 
         [0014]    A registered user of an e-mail forwarding server of the present invention sends an e-mail message to a customized recipient&#39;s e-mail address. Because the e-mail forwarding server is the Mail Exchange (MX) authority for the domain of the customized recipient e-mail address, the message is sent to the e-mail forwarding server. The e-mail forwarding server contains a database including user&#39;s actual e-mail addresses and their associated alias e-mail addresses. Once the e-mail forwarding server receives the message, it first extracts the intended recipient&#39;s e-mail address from the message, then replaces message sender&#39;s e-mail address with its associated alias e-mail address, and delivers the message to the original intended recipient. To the recipient the message seems to be sent from the e-mail forwarding server directly and the sender&#39;s e-mail address is user&#39;s alias e-mail address. Hence the user&#39;s actual e-mail identity is not exposed to the recipient. When the e-mail forwarding server receives an e-mail message sent to the user&#39;s alias e-mail address, it automatically forwards the message to the user&#39;s registered actual e-mail address stored in the database. 
         [0015]    The present invention also provides various techniques of customizing recipient e-mail address, which allow users easily choose one of their alias e-mail addresses, or use system generated random alias e-mail addresses, or schedule message delivery. 
         [0016]    The present invention provides advantages in that protecting people&#39;s actual e-mail identity from being exposed on the Internet, which can be used with any e-mail clients or devices. It does not require any software installation or switching between different e-mail accounts. 
     
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0017]      FIG. 1  is a block diagram depicting a network system in which a preferred embodiment of the invention may be practiced. 
           [0018]      FIG. 2  is a look-up table used by the present invention. 
           [0019]      FIG. 3  is a diagram illustrating an exemplary embodiment of e-mail message forwarding process in accordance with the present invention. 
           [0020]      FIGS. 4A ,  4 B and  4 C are diagrams illustrating exemplary embodiments of customizing recipient&#39;s e-mail addresses in accordance with the present invention. 
           [0021]      FIG. 5  is a diagram illustrating an exemplary embodiment of e-mail message forwarding process in accordance with the present invention. 
           [0022]      FIGS. 6A and 6B  present a flow chart showing detail of steps of processing message envelope addresses and headers in an e-mail forwarding server. 
           [0023]      FIG. 7  is a diagram showing a mail flow of sending and receiving e-mail messages in accordance with an embodiment of the present invention. 
           [0024]      FIG. 8  is a diagram illustrating another exemplary embodiment of e-mail message forwarding process in accordance with the present invention. 
           [0025]      FIG. 9  is a diagram illustrating another exemplary embodiment of e-mail message forwarding process in accordance with the present invention. 
           [0026]      FIG. 10  is a diagram illustrating yet another exemplary embodiment of e-mail message forwarding process in accordance with the present invention. 
           [0027]      FIG. 11  is a diagram illustrating an exemplary embodiment of selecting alias e-mail address in accordance with the present invention. 
           [0028]      FIG. 12  is another look-up table used by the present invention. 
           [0029]      FIG. 13  is a diagram illustrating an exemplary embodiment of using system generated random alias e-mail address in accordance with the present invention. 
           [0030]      FIG. 14  is a diagram illustrating an exemplary embodiment of scheduling e-mail message delivery in accordance with the present invention. 
           [0031]      FIG. 15  is a diagram illustrating an exemplary embodiment of using multiple predetermined delimited characters and parameters in accordance with the present invention. 
           [0032]      FIG. 16  is a diagram illustrating another exemplary embodiment of using multiple predetermined delimited characters and parameters in accordance with the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0033]    In the following description, the different embodiments of the invention are explained from the point of view of showing how a user redirects e-mail messages to an e-mail forwarding server via use of customized recipient e-mail addresses and how an e-mail forwarding server protects the user&#39;s actual e-mail identity. 
       Preferred Environment 
       [0034]      FIG. 1  is a block diagram of a network system for practicing the preferred embodiments of the present invention. The system includes a device  101  for sending and receiving e-mail messages, an e-mail forwarding server  103 , a device  105  for sending and receiving e-mail messages, and a network communications mechanism  107 . 
         [0035]    The device  101  can be any device, which is capable of generating and transmitting e-mail messages (e.g., pager, mobile phone, PDA, Blackberry, and PC, etc.). 
         [0036]    The e-mail forwarding server  103  is provided with software programmed to perform the below described steps necessary to operate the present invention. As shown in  FIG. 2 , the software program in e-mail forwarding server  103  includes a look-up table  200 , which is programmable to provide a subscriber&#39;s actual e-mail address  202  associated with a pre-programmed subscriber&#39;s alias e-mail address  204 . The look-up table  200  may include a plurality of alias e-mail addresses ( 204 +N), with each alias e-mail address being associated with one or more subscriber&#39;s actual e-mail addresses ( 202 +M). 
         [0037]    The device  105  can be any device, which is capable of generating and transmitting e-mail messages (e.g., pager, mobile phone, PDA, Blackberry, and PC). 
         [0038]    The network communications mechanism  107  provides a mechanism for facilitating communication between device  101 , e-mail forwarding server  103 , and device  105 . As is well known, the Internet provides network communication lines between device  101 , e-mail forwarding server  103 , and device  105  through Internet Service Providers (ISP). 
         [0039]    It is to be appreciated that in this description of the present invention e-mail forwarding server  103 , mention is made to both a “user” and “subscriber” of e-mail forwarding server  103 . It is to be understood that a “user” of e-mail forwarding server  103  refers to anyone who is capable of transmitting e-mail messages and accessing e-mail forwarding server  103  when it is desired to use an alias e-mail address as the sender&#39;s e-mail address to transmit messages to a recipient. 
         [0040]    A “subscriber” of e-mail forwarding server  103  refers to anyone who subscribes to the e-mail forwarding service of server  103  in which the subscriber registers both at least one alias e-mail address  204  and at least one actual e-mail address  202  in e-mail forwarding server  103 . 
         [0041]    A subscriber or user may also be referred to as a “sender” or “recipient” of an e-mail using the present invention. E-mail forwarding server  103  is accessible by any user. 
         [0042]    In accordance with the present invention as shown in  FIG. 3 , Sender  301  is a subscriber of e-mail forwarding server  103 . Sender  301  also has another e-mail account with an actual e-mail address (e.g., joe.smith@mycorp.com) in a different e-mail system. Sender  301  desires to send an e-mail message directly from his/her actual e-mail account to recipient  305  (e.g., alice@yahoo.com), but doesn&#39;t want to let recipient  305  know his/her actual e-mail address (e.g., joe.smith@mycorp.com). 
         [0043]    In a preferred embodiment, first sender  301  accesses a designated account in e-mail forwarding server  103  via any known means such as the Internet, and registers an actual e-mail address (e.g., joe.smith@mycorp.com) and its associated alias e-mail address (e.g., joat23@akapost.com) in e-mail forwarding server  103 . Second sender  301  uses his/her actual e-mail account to compose an e-mail message  303   a , and follows the “Customizing E-Mail Address” method described below to create a customized recipient&#39;s e-mail address (e.g., alice@yahoo.com.akapost.com). Next sender  301  sends the message to this customized recipient&#39;s e-mail address. 
       Customizing E-Mail Address 
       [0044]    If the domain name (e.g., yahoo.com) of a recipient&#39;s e-mail address (e.g., alice@yahoo.com) is not the same as an e-mail forwarding server&#39;s authoritative e-mail domain name (e.g., akapost.com), an e-mail sender needs to customize the recipient&#39;s e-mail address to redirect the message to the e-mail forwarding server. The method of customizing e-mail address is now described below with reference to  FIGS. 4A ,  4 B and  4 C. 
         [0045]    In a preferred embodiment as shown in  FIG. 4A , sender  301  appends a domain name extension string “.akapost.com” to recipient&#39;s e-mail address (e.g., alice@yahoo.com) to generate a customized recipient&#39;s e-mail address (e.g., alice@yahoo.com.akapost.com) and sends message  303   a  to this customized recipient&#39;s e-mail address. Since e-mail forwarding server  103  is the Mail Exchange (MX) authority for “akapost.com” domain, so message  303   a  is delivered to e-mail forwarding server  103 . 
         [0046]    In alternative embodiments as shown in  FIGS. 4B and 4C , sender  301  replaces “@” character in recipient&#39;s e-mail address (e.g., alice@yahoo.com) with a “+” (plus) or “_”(underscore) character to generate a new string (e.g., alice+yahoo.com or alice_yahoo.com), then appends a domain name extension “@akapost.com” to this new string to create a new e-mail address (e.g., alice+yahoo.com@akapost.com or alice_yahoo.com@akapost.com), then sends message  401   a  or  402   a  to this new customized recipient&#39;s e-mail address. These methods also redirect message  401   a  or  402   a  to e-mail forwarding server  103 . 
         [0047]    In the following, embodiments of the present invention are based on the first preferred “Customizing E-Mail Address” embodiment as shown in  FIG. 4A  but may be modified to suit another “Customizing E-Mail Address” embodiment, such as the embodiment described above with reference to  FIGS. 4B  or  4 C, to produce substantially the same results. 
       Forwarding E-mail Message 
       [0048]    In a preferred embodiment as shown in  FIG. 5 , after e-mail forwarding server  103  receives message  303   a  sent to the customized recipient&#39;s e-mail address (e.g., alice@yahoo.com.akapost.com) from sender  301  (e.g., joe.smith@mycorp.com), it starts processing message  303   a &#39;s envelope addresses and message headers, and generates a re-addressed message  303   b , then delivers message  303   b  to the intended recipient  305 &#39;s e-mail address (e.g., alice@yahoo.com). The detail steps are described below as shown in  FIGS. 6A and 6B : 
         [0049]    Step  601 :
       E-mail forwarding server  103  uses the envelope recipient address (e.g., alice@yahoo.com.akapost.com) of the message to search lookup table  200  and determine if an associated actual e-mail address exists.       
 
         [0051]    Step  602 :
       If e-mail forwarding server  103  does find the associated actual e-mail address in “Step 601”, it uses this associated actual e-mail address as the intended recipient&#39;s e-mail address and skips “Step 603”, “Step 604” and “Step 605”.       
 
         [0053]    Step  603 :
       If e-mail forwarding server  103  does not find the associated actual e-mail address in “Step 601”, it checks if any character exists between “@” character and “akapost.com” string in the envelope recipient address (e.g., alice@yahoo.com.akapost.com) of the message.       
 
         [0055]    Step  604 :
       If the result of “Step 603” is true, e-mail forwarding server  103  obtains the intended recipient&#39;s e-mail address (e.g., alice@yahoo.com) by removing “.akapost.com” string in the envelope recipient address (e.g., alice@yahoo.com.akapost.com) of the message.       
 
         [0057]    Step  605 :
       If the result of “Step 603” is false, e-mail forwarding server  103  uses the envelope recipient address of the message as the intended recipient&#39;s e-mail address.       
 
         [0059]    Step  606 :
       After e-mail forwarding server  103  obtains the intended recipient&#39;s e-mail address in “Step 602” or “Step 604” or “Step 605”, it substitutes all occurrences of the existing recipient e-mail address (e.g., alice@yahoo.com.akapost.com) in the envelope recipient address and message headers with the intended recipient&#39;s e-mail address (e.g., alice@yahoo.com).       
 
         [0061]    Step  607 :
       Then e-mail forwarding server  103  uses the envelope sender address (e.g., joe.smith@mycorp.com) of the message to search lookup table  200  and determine if an associated alias e-mail address (e.g., joat23@akapost.com) exists.       
 
         [0063]    Step  608 :
       If e-mail forwarding server  103  does find the associated alias e-mail address (e.g., joat23@akapost.com) in the lookup table  200  in “Step 607”, it substitutes all occurrences of the existing sender e-mail address (e.g., joe.smith@mycorp.com) in the envelope sender address and message headers with the associated alias e-mail address (e.g., joat23@akapost.com).       
 
         [0065]    Step  609 :
       If e-mail forwarding server  103  could not find the associated alias e-mail address in the lookup table  200  in “Step 607” and the result of “Step 601” is true (as shown in  FIG. 6A ), it follows the methods described in the “Customizing E-Mail Address” section to customize the e-mail address in the envelope sender address and creates a customized sender&#39;s e-mail address, then substitutes all occurrences of the existing sender e-mail address in the envelope sender address and message headers with this new customized sender&#39;s e-mail address.       
 
         [0067]    Step  610 :
       If e-mail forwarding server  103  could not find the associated alias e-mail address in the lookup table in “Step 607” and the result of “Step 601” is false (as shown in  FIG. 6B ), it bounces back the e-mail message, and notifies the sender that the sender&#39;s actual e-mail address has not been registered in e-mail forwarding server  103  and users need to register first before they can use this e-mail forwarding service. E-mail forwarding server  103  stops further processing of this message.       
 
         [0069]    Step  611 :
       After e-mail forwarding server  103  replaces the recipient and sender e-mail addresses in the envelope addresses and message headers, it delivers this re-addressed message to the intended recipient&#39;s e-mail address (e.g., alice@yahoo.com).       
 
         [0071]    In a preferred embodiment as shown in  FIG. 7  (Mail flow direction is from  721  to  728 ), when recipient  305  receives message  303   b , recipient  305  doesn&#39;t know sender  301 &#39;s actual e-mail address (e.g., joe.smith@mycorp.com) because the original sender&#39;s e-mail address has been replaced with the sender&#39;s alias e-mail address (e.g., joat23@akapost.com). To recipient  305  message  303   b  seems to be sent directly from sender  301 &#39;s alias e-mail address (e.g., joat23@akapost.com). When recipient  305  sends a reply message  701   a  to  301 , message  701   a  is sent to  301 &#39;s alias e-mail address (e.g., joat23@akapost.com). 
         [0072]    After e-mail forwarding server  103  receives message  701   a  from  305 , it follows steps from “Step 601” to “Step 611” (as shown in  FIGS. 6A and 6B ) to process message  701   a &#39;s envelope addresses and message headers, and generate a re-addressed message  701   b , then deliver message  701   b  to the intended recipient&#39;s e-mail address. Because the result of “Step 602” (as shown in  FIG. 6A ) is true in this example, so the intended recipient&#39;s e-mail address is  301 &#39;s actual e-mail address (e.g., joe.smith@mycorp.com). Therefore  301 &#39;s actual e-mail account receives this reply message sent from  305 . 
         [0073]    As described above, once users registered their actual e-mail addresses and alias e-mail addresses in the e-mail forwarding server of this invention, the users are able to send or receive e-mail messages directly through their registered actual e-mail accounts without exposing their actual e-mail addresses to recipients. 
         [0074]      FIG. 8  illustrates another example of forwarding e-mail message according to an embodiment of the present invention. As shown in  FIG. 8 , a subscribed sender  301  sends an e-mail message  801   a  to a subscribed recipient  802 &#39;s e-mail address (e.g., mike1968@akapost.com). Since the domain name (e.g., akapost.com) of recipient  802 &#39;s e-mail address (e.g., mike1968@akapost.com) is the same as e-mail forwarding server  103 &#39;s authoritative e-mail domain name (e.g., akapost.com), sender  301  doesn&#39;t need to customize recipient  802 &#39;s e-mail address (e.g., mike1968@akapost.com). Sender  301  sends message  801   a  directly to recipient  802 &#39;s e-mail address (e.g., mike1968@akapost.com). 
         [0075]    After e-mail forwarding server  103  receives message  801   a , it follows steps from “Step 601” to “Step 611” (as shown in  FIGS. 6A and 6B ) to process message  801   a &#39;s envelope addresses and message headers, and generate a re-addressed message  801   b , then deliver message  801   b  to recipient  802 &#39;s registered actual e-mail address (e.g., smike@aol.com). 
         [0076]      FIG. 9  illustrates another example of forwarding e-mail message according to an embodiment of the present invention. As shown in  FIG. 9 , a non-subscribed sender  903  (e.g., emily@hotmail.com) sends an e-mail message  901   a  to a subscribed recipient  802 &#39;s e-mail address (e.g., mike1968@akapost.com). Since sender  903  is not a subscriber of e-mail forwarding server  103 , sender  903  will not modify recipient  802 &#39;s e-mail address. Sender  903  sends message  901   a  directly to recipient  802 &#39;s e-mail address (e.g., mike1968@akapost.com). The message is delivered to e-mail forwarding server  103 . 
         [0077]    After e-mail forwarding server  103  receives message  901   a , it follows steps from “Step 601” to “Step 611” (as shown in  FIGS. 6A and 6B ) to process message  901   a &#39;s envelope addresses and message headers, and generate a re-addressed message  901   b , then deliver message  901   b  to recipient  802 &#39;s registered actual e-mail address (e.g., smike@aol.com). 
         [0078]      FIG. 10  illustrates another example of forwarding e-mail message according to an embodiment of the present invention. As shown in  FIG. 10 , a non-subscribed sender  903  (e.g., emily@hotmail.com) sends an e-mail message  1001  to a non-subscribed recipient  305 &#39;s e-mail address (e.g., alice@yahoo.com). Since sender  903  is not a subscriber of e-mail forwarding server  103 , sender  903  should not modify any recipient&#39;s e-mail address. But for some reasons if sender  903  wants to use the e-mail forwarding service of the present invention and follows the methods described in the “Customizing E-Mail Address” section to create a customized e-mail address (e.g., alice@yahoo.com.akapost.com), and sends message  1001  to this customized e-mail address (e.g., alice@yahoo.com.akapost.com). As a result, the message is sent to e-mail forwarding server  103 . 
         [0079]    After e-mail forwarding server  103  receives message  1001 , it follows steps from “Step 601” to “Step 611” (as shown in  FIGS. 6A and 6B ) to process message  1001 &#39;s envelope addresses and message headers. Since sender  903  is not a registered user and recipient  305 &#39;s customized e-mail address (e.g., alice@yahoo.com.akapost.com) doesn&#39;t have an associated alias e-mail address, e-mail forwarding server  103  bounces back message  1001 , and notifies sender  903  with message  1002  that sender  903 &#39;s e-mail address has not been registered in e-mail forwarding server  103  and users need to register first before they can use this e-mail forwarding service. 
         [0080]    In accordance with the present invention, as will be discussed further below the subscriber can also use various customizing recipient e-mail address methods to easily select different alias e-mail addresses, or use system generated random alias e-mail addresses, or schedule message delivery. 
       Selecting Alias E-Mail Address 
       [0081]    In another embodiment of the present invention, a user may have multiple alias e-mail addresses registered in an e-mail forwarding server and the user can a specific predetermined delimited character and corresponding parameter to select one of alias e-mail addresses to send e-mail messages. As shown in  FIG. 11 , sender  301  registered multiple alias e-mail addresses and their associated alias short names (as shown in FIG.  12 ) in e-mail forwarding server  103 . If sender  301  desires to use one of alias e-mail addresses (e.g., superman55@akapost.com) to send an e-mail message to recipient  305  (e.g., alice@yahoo.com), sender  301  first uses the methods described in the “Customizing E-Mail Address” section to create a customized recipient&#39;s e-mail address (e.g., alice@yahoo.com.akapost.com), next adds a specific predetermined delimited character (e.g., a) and a pre-registered alias short name (e.g., superman55) into the customized recipient&#39;s e-mail address to generate a new customized recipient&#39;s e-mail address (e.g., alice@yahoo.com.a.superman55.akapost.com), then sends e-mail message  1101   a  to this e-mail address. 
         [0082]    The “a” character in this new customized recipient&#39;s e-mail address (e.g., alice@yahoo.com.a.superman55.akapost.com) is an example of the predetermined delimited character. The e-mail forwarding server can use it to identify and extract the alias short name (e.g., superman55) from the customized recipient&#39;s e-mail address (e.g., alice@yahoo.com.a.superman55.akapost.com). The alias short name is used for the e-mail forwarding server to select a different alias e-mail address. In the e-mail forwarding server every alias short name is associated with an alias e-mail address (as shown in  FIG. 12 ). By default the alias short name is same as the local part of its associated alias e-mail address (e.g., superman55). 
         [0083]    After e-mail forwarding server  103  receives message  1101   a , it first uses the predetermined delimited character (e.g., a) in the envelope recipient address (e.g., alice@yahoo.com.a.superman55.akapost.com) to identify and extract alias short name  1204  (e.g., superman55), second obtains the intended recipient&#39;s e-mail address (e.g., alice@yahoo.com) by removing all predetermined delimited character and parameter and “.akapost.com” string (e.g., .a.superman55.akapost.com) in the envelope recipient address (e.g., alice@yahoo.com.a.superman55.akapost.com), and substitutes all occurrences of the existing recipient e-mail address in the envelope recipient address and message headers with the intended recipient&#39;s e-mail address (e.g., alice@yahoo.com), third uses the extracted alias short name  1204  (e.g., superman55) and the envelope sender address (e.g., joe.smith@mycorp.com) to search lookup table  1200  (as shown in  FIG. 12 ) and obtains associated alias e-mail address  1202  (e.g., superman55@akapost.com), and substitutes all occurrences of the existing sender e-mail address in the envelope sender address and message headers with alias e-mail address  1202  (e.g., superman55@akapost.com), then delivers this re-addressed message  1101   b  to recipient  305 . 
         [0084]    This process is similar with the process described in the steps from “Step 601” to “Step 611” in the “Forwarding E-mail Message” section, except using more sophisticated methods to extract alias short name and intended recipient&#39;s e-mail address, and using a different alias e-mail address. 
         [0085]    If sender  301  desires to use another alias e-mail address (e.g., js1977@akapost.com) to send an e-mail message to recipient  305 , sender  301  can use the same methods described above to create a new customized recipient&#39;s e-mail address (e.g., alice@yahoo.com.a.js.akapost.com) and submit the e-mail message to this e-mail address. 
         [0086]    E-mail forwarding server  103  can define one of alias e-mail addresses as a user&#39;s default alias e-mail address (e.g., joat23@akapost.com). Therefore when the user sends an e-mail message without using any predetermined delimited character, e-mail forwarding server  103  will automatically select the default alias e-mail address (e.g., joat23@akapost.com) to deliver the message. 
         [0087]    The specific predetermined delimited character and corresponding parameter can be any other valid Internet host name character(s) (e.g., letters, numbers, or hyphens). But they have to be completely defined before launching the e-mail forwarding service of the present invention. The e-mail forwarding service also needs to provide a user guide explains how to use this specific predetermined delimited character and corresponding parameter. 
       Using System Generated Random Alias E-mail Address 
       [0088]    In another embodiment of the present invention, a user can use a specific predetermined delimited character and corresponding parameter to choose using system generated random alias e-mail addresses to send e-mail messages. As shown in  FIG. 13 , if sender  301  desires to deliver an e-mail message to recipient  305  (e.g., alice@yahoo.com) using a system generated random alias e-mail address, sender  301  first uses the methods described in the “Customizing E-Mail Address” section to create a customized recipient&#39;s e-mail address (e.g., alice@yahoo.com.akapost.com), next adds a predetermined delimited character (e.g., s) and a lifespan parameter (e.g., 3 d) into the customized recipient&#39;s e-mail address to generate a new customized recipient&#39;s e-mail address (e.g., alice@yahoo.com.s.3d.akapost.com), then sends e-mail message  1301   a  to this e-mail address. 
         [0089]    The “s” character in this new customized recipient&#39;s e-mail address (e.g., alice@yahoo.com.s.3d.akapost.com) is an example of the predetermined delimited characters. The e-mail forwarding server can use it to identify and extract the lifespan parameter (e.g., 3 d) from the customized recipient&#39;s e-mail address (e.g., alice@yahoo.com.s.3d.akapost.com). The lifespan parameters are specified by using suffixes “y”, “m”, and “d”. The “3d” means three days. 
         [0090]    After e-mail forwarding server  103  receives message  1301   a , it first uses a predetermined delimited character (e.g., s) in the envelope recipient address (e.g., alice@yahoo.com.s.3d.akapost.com) to identify and extract lifespan information (e.g., 3 d), second obtains the intended recipient&#39;s e-mail address (e.g., alice@yahoo.com) by removing all predetermined delimited character and parameter and “.akapost.com” string (e.g., .s.3d.akapost.com) in the envelope recipient address (e.g., alice@yahoo.com.s.3d.akapost.com), and substitutes all occurrences of the existing recipient e-mail address in the envelope recipient address and message headers with the intended recipient&#39;s e-mail address (e.g., alice@yahoo.com), third generates a random alias e-mail address (e.g., s060605dmv@akapost.com), and substitutes all occurrences of the existing sender e-mail address in the envelope sender address and message headers with this system generated random alias e-mail address (e.g., s060605dmv@akapost.com), then delivers this re-addressed message  1301   b  to recipient  305 . 
         [0091]    This process is similar with the process described in the steps from “Step 601” to “Step 611” in the “Forwarding E-mail Message” section, except using more sophisticated methods to extract lifespan information, and using a system generated random alias e-mail address. Since the lifespan for this system generated random alias e-mail address (e.g., s060605dmv@akapost.com) is three days, so this alias e-mail address (e.g., s060605dmv@akapost.com) will be valid for 3 days only. After 3 days, this system generated random alias e-mail address (e.g., s060605dmv@akapost.com) will not accept any e-mail messages. 
         [0092]    The specific predetermined delimited character and corresponding parameter mentioned above can be any other valid Internet host name character(s) (e.g., letters, numbers, or hyphens). But they have to be completely defined before launching the e-mail forwarding service of the present invention. The e-mail forwarding service also needs to provide a user guide explains how to use this specific predetermined delimited character and corresponding parameter. 
       Scheduling E-Mail Message Delivery 
       [0093]    In another embodiment of the present invention, a user can use a specific predetermined delimited character and corresponding parameter to schedule date and time to deliver e-mail messages. As shown in  FIG. 14 , if sender  301  desires to deliver an e-mail message to recipient  305  (e.g., alice@yahoo.com) 2 days 3 hours and 50 minutes later, sender  301  first uses the methods described in the “Customizing E-Mail Address” section to create a customized recipient&#39;s e-mail address (e.g., alice@yahoo.com.akapost.com), next adds a predetermined delimited character (e.g., t) and a delivery data/time parameter (e.g., 2d3h50m) into the customized recipient&#39;s e-mail address to generate a new customized recipient&#39;s e-mail address (e.g., alice@yahoo.com.t.2d3h50m.akapost.com), then sends e-mail message  1401   a  to this e-mail address. 
         [0094]    The “t” character in this new customized recipient&#39;s e-mail address (e.g., alice@yahoo.com.t.2d3h50m.akapost.com) is an example of the predetermined delimited characters. The e-mail forwarding server can use it to identify and extract the delivery data/time parameter (e.g., 2d3h50m) from the customized recipient&#39;s e-mail address (e.g., alice@yahoo.com.t.2d3h50m.akapost.com). The delivery data/time intervals are specified by using suffixes “d”, “h”, and “m”. The “2d3h50m” means 2 days, 3 hours, and 50 minutes. 
         [0095]    After e-mail forwarding server  103  receives message  1401   a , it first uses a predetermined delimited character (e.g., t) in the envelope recipient address (e.g., alice@yahoo.com.t.2d3h50m.akapost.com) to identify and extract delivery data/time information (e.g., 2d3h50m), second obtains the intended recipient&#39;s e-mail address (e.g., alice@yahoo.com) by removing all predetermined delimited character and parameter and “.akapost.com” string (e.g., .t.2d3h50m.akapost.com) in the envelope recipient address (e.g., alice@yahoo.com.t.2d3h50m.akapost.com), and substitutes all occurrences of the existing recipient e-mail address in the envelope recipient address and message headers with the intended recipient&#39;s e-mail address (e.g., alice@yahoo.com), third uses the envelope sender address (e.g., joe.smith@mycorp.com) to search lookup table  200  (as shown in  FIG. 2 ) and obtains associated alias e-mail address  204  (e.g., joat23@akapost.com), and substitutes all occurrences of the existing sender e-mail address in the envelope sender address and message headers with alias e-mail address  204  (e.g., joat23@akapost.com), then delivers this re-addressed message  1401   b  to recipient  305  after 2 days, 3 hours, and 50 minutes. 
         [0096]    This process is similar with the process described in the steps from “Step 601” to “Step 611” in the “Forwarding E-mail Message” section, except using more sophisticated methods to extract delivery data/time information and intended recipient&#39;s e-mail address, and delivering messages at a scheduled date/time. 
         [0097]    The specific predetermined delimited character and corresponding parameter mentioned above can be any other valid Internet host name character(s) (e.g., letters, numbers, or hyphens). But they have to be completely defined before launching the e-mail forwarding service of the present invention. The e-mail forwarding service also needs to provide a user guide explains how to use this specific predetermined delimited character and corresponding parameter. 
       Using Multiple Parameters 
       [0098]    In another embodiment of the present invention, a user can mix some predetermined delimited characters and parameters mentioned above to meet some special requests. As shown in  FIG. 15 , if sender  301  desires to use one of alias e-mail addresses (e.g., js1977@akapost.com) to deliver an e-mail message to recipient  305  (e.g., alice@yahoo.com) 3 days later, sender  301  adds multiple predetermined delimited characters (e.g., a, t) and parameters (e.g., js, 2d3h50m) into the customized recipient&#39;s e-mail address (e.g., alice@yahoo.com.akapost.com) created by using the methods described in the “Customizing E-Mail Address” section to generate a new customized recipient&#39;s e-mail address (e.g., alice@yahoo.com.a.js.t.3d.akapost.com), and sends e-mail message  1501   a  to this e-mail address. 
         [0099]    As another example of using multiple predetermined delimited characters and parameters according to an embodiment of the present invention shown in  FIG. 16 , if sender  301  desires to use a system generated random alias e-mail address (e.g., s060605dmv@akapost.com) to send an e-mail message to recipient  305  (e.g., alice@yahoo.com) 3 days later, sender  301  adds multiple predetermined delimited characters (e.g., s, t) and parameters (e.g., 5d, 3d) into the customized recipient&#39;s e-mail address (e.g., alice@yahoo.com.akapost.com) created by using the methods described in the “Customizing E-Mail Address” section to generate a new customized recipient&#39;s e-mail address (e.g., alice@yahoo.com.s.5d.t.3d.akapost.com), and sends e-mail message  1601   a  to this e-mail address. 
         [0100]    After e-mail forwarding server  103  receives messages  1501   a  or  1601   a , it follows the same procedures described above in the “Selecting Alias E-mail Address”, “Using System Generated Random Alias E-mail Address” and “Scheduling E-mail Message Delivery” sections to process message  1501   a  or  1601   a , and delivers the messages in the way sender  301  intended. 
         [0101]    These specific predetermined delimited characters and corresponding parameters mentioned above can be any other valid Internet host name characters (e.g., letters, numbers, or hyphens). But they have to be completely defined before launching the e-mail forwarding service of the present invention. The e-mail forwarding service also needs to provide a user guide explains how to use these specific predetermined delimited characters and corresponding parameters. 
         [0102]    The present invention has been described in terms of a number of preferred embodiments. However, it will be understood by those of ordinary skill in the art that various modifications and improvements may be made to the invention as described, without departing from the spirit and scope of the invention.