Abstract:
Systems and methods are described for creating and managing Global Session Identifiers (GSIDs) for communication sessions. GSIDs provide a way to globally identify communication sessions including those communication sessions that have experienced one or more topology changes. The GSID may be considered a header itself or a value within a header and information contained within a GSID can be used to trace backwards through time to find the session segments that led up to (or exist concurrently to) a currently signaled session.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit of U.S. Provisional Application No. 61/599,281 filed Feb. 15, 2012, the entire disclosure of which is hereby incorporated herein by reference. 
     
    
     FIELD OF THE DISCLOSURE 
       [0002]    The present disclosure is generally directed toward communications and more specifically toward unified communications. 
       BACKGROUND 
       [0003]    In the Session Initiation Protocol (SIP), a large number of features involve two or more end-to-end sessions. Examples of such features include call transfers, conferencing, etc. Also in SIP, each point-to-point session is independent—resulting in independent SIP Dialog Ids for every session (i.e., call-id+tags). Some SIP Architectures employ Back-to-Back User Agents (B2BUAs) for various purposes (e.g., sequenced applications). The problem with employing B2BUAs rather than proxies is that B2BUAs break the coherency of the point-to-point calls. In other words, when a single session traverses B2BUA based elements, the SIP dialog ids are modified as defined by SIP standards. 
         [0004]    Current solutions like P-Charging-Vector (IMS Charging ID value correlates a SIP call as it traverses different sequenced applications including B2BUAs), Universal Caller ID (An identifier to tag a contact center call as it traverse various elements like announcement server, self-service portal etc. before landing at the agent), and Session-Id provide a unique identifier to correlate the parts of an end-to-end session as it traverses B2BUAs. 
         [0005]    However, for the SIP features comprising multiple individual sessions (that traverse via B2BUAs or proxies), there is no easy way to correlate those sessions. Indeed, while there are currently solutions to overcome the problem of B2BUAs modifying Dialog Ids, there is no currently viable solution to address the problem arising due to call topology modification. 
       SUMMARY 
       [0006]    It is with respect to the above issues and other problems that the embodiments presented herein were contemplated. In particular, embodiments of the present disclosure provide a simple and convenient way of correlating communications sessions or dialogs. As can be appreciated, the terms session, communication session, dialog, SIP dialog, and the like will be used interchangeably to refer to any communication between two or more individuals established with communication equipment over a communication network. 
         [0007]    Embodiments of the present disclosure introduce the concept of a Global Session Identifier (GSID). The proposed GSID, in some embodiments, is implemented as a token that identifies a session end-to-end (from originator to destination) even as the session traverses B2BUA-based elements resulting in a chain of multiple SIP-based dialog ids. 
         [0008]    The GSID provides the ability to logically tie different seemingly independent sessions/calls together. In some embodiments, the GSID may be combined with Endpoint View information and the GSID can tie the Endpoint view of the session participants (e.g., originator and destination) together. As such, the GSID can be created upon receiving a new request. This may cause the GSID to be globally unique in time and space. Additional details regarding the construction and format of an EPV are described, for example, in U.S. Provisional Patent Application No. 61/582,176, filed Dec. 30, 2011, the entire contents of which are hereby incorporated herein by reference. 
         [0009]    In some embodiments, the GSID is not created by combining the two EPVs. Instead, the GSID is created at the time of the call originator&#39;s EPV (EPV-o) creation. Then, the same GSID is associated with the destination&#39;s EPV (EPV-t) when Session Manager (SM) (or any similar server that controls call and signaling flows in a communication system, such as a communication server) receives the first response from the destination. After the GSID is created, the value of the GSID is carried in a Global Session Id header in all SIP requests and responses that are subsequently exchanged during that session. Furthermore, B2BUAs are allowed and expected to pass the GSID without modification since the GSID is not contained in a modified header. 
         [0010]    The EPV is a header that provides the GRUU and dialog ID known to the endpoint. This is rarely the Contact URI and dialog ID within the message itself because B2BUAs change these headers. 
         [0011]    A “GRUU” is a Globally Routable User Agent (UA) URI—a URI that defines a particular device rather than a user. This is generally not simply an IP address: due to Network Address Translation (NAT) and firewalls, IP addresses are rarely globally routable. 
         [0012]    If a new request generated in the context of an existing dialog does not contain the correlation id (e.g., third-party device based call transfer flow), SM creates a new GSID. Later, SM associates the independent sessions (sessions with different GSIDs) based on the GSID parameter in various mid-dialog SIP requests/responses, new requests, (e.g., REFER-To header, INVITE-R R-URI, INVITE-J R-URI, Contact header, Other headers and parameters (e.g., call-info, av-ouri parameter)). When the association between two GSIDs is established, SM fills and inserts the nature/reason of the GSID association in the GSID header as an associated GSID. With the association of GSIDs in the GSID header, SM is capable of creating a global session identifier that is persistent even when call topology changes due to one or more of changes in session participants/users, changes in devices that are involved in the session, changes in which endpoint has control over the session, and/or changes in the type of control that a device exerts over a session. 
         [0013]    In some embodiments, if the received out-of-dialog request does not contain a GSID, SM creates a new GSID. SM then looks for the association of the current session request with other sessions by examining the contents of the current SIP message. The association may be detected by examining the contents of the R-URI, headers, parameters, and attachments of the SIP message. The places SM examines for detecting the potential association include, but are not limited to, the REFER-To header, INVITE-Join R-URI, INVITE-Replace R-URI, Contact header, Call-Info header, av-ouri parameter, attachments, and other proprietary headers and parameters of the SIP message. In some embodiments, SM examines subsequent responses and mid-dialog requests and responses for potential association to detect associations that are established and/or becomes visible later in the call and feature phase. If there is no association, SM inserts the GSID in the Global Session ID header. If and when an association among independent sessions is detected, SM inserts the association by inserting additional parameters to the Global Session Id header identifying the GSID of the associated session (e.g., inserting the current GSID of the original session as well as the GSID of the new session that is associated with the original session perhaps along with other information describing why the association has been created). In some embodiments, SM also inserts the source of the association as a parameter in the header. With the association of the GSIDs, SM is capable of creating, labeling, and logging the messages with the Global Session ID header that correlates all portions of a call even when the call topology changes due to one or more of changes in session participants/users, changes in devices that are involved in the session, changes in which endpoint has control over the session, and/or changes in the type of control that a device exerts over a session. 
         [0014]    In some embodiments, there is enough information in a GSID Header to trace backwards through time to find the session segments that led up to (or exist concurrently to) the currently signaled session as long as the GSID Headers are captured along with any session databases, signaling traces, error logs, or call records. Given a GSID or associated GSID, embodiments of the present disclosure enable an easy-to-execute and search among the sessions, logs, or traces to find any SIP Sessions also containing a matching GSID. 
         [0015]    As used herein, the term “GSID” or “Global Session Identifier” may refer to any number, character, set of numbers, set of characters, alphanumeric sequence, string, or collection of elements that identify a communication session. The GSID may be randomly, pseudo-randomly, or sequentially generated in response to the creation of a new communication session. 
         [0016]    The term “GSID Header” or “Global Session ID Header”, as used herein, may refer to any portion of a message that carries a GSID, multiple GSIDs, or information that describes an association between GSIDs. In some embodiments, it may be possible to include a first GSID, a second GSID, and a description of the reason why the first and second GSIDs have been associated within the Global Session ID Header. While the term “header” is used to describe the portion of a message (e.g., SIP message, IP packet, etc.) that carries the identification information, it should be appreciated that such identification information may be included in a header, sub-header, footer, payload, or any other content-bearing portion of a message. 
         [0017]    Further still, the term GSID or Global Session Identifier may also be used to describe the header that carries the identification information of one or more communication sessions. Accordingly, session identification information may be referred to as a GSID or the container (e.g., header, footer, sub-header, payload, message body, etc.) of the identification information may be referred to as a GSID without departing from the scope of the present disclosure. Where the GSID is used to refer to the container of identification information, the GSID may include identification information for multiple sessions (e.g., a combination of session identifiers), information describing that an association between sessions has been created, and/or information describing why an association between sessions has occurred. 
         [0018]    The phrases “at least one”, “one or more”, and “and/or” are open-ended expressions that are both conjunctive and disjunctive in operation. For example, each of the expressions “at least one of A, B and C”, “at least one of A, B, or C”, “one or more of A, B, and C”, “one or more of A, B, or C” and “A, B, and/or C” means A alone, B alone, C alone, A and B together, A and C together, B and C together, or A, B and C together. 
         [0019]    The term “a” or “an” entity refers to one or more of that entity. As such, the terms “a” (or “an”), “one or more” and “at least one” can be used interchangeably herein. It is also to be noted that the terms “comprising”, “including”, and “having” can be used interchangeably. 
         [0020]    The term “automatic” and variations thereof, as used herein, refers to any process or operation done without material human input when the process or operation is performed. However, a process or operation can be automatic, even though performance of the process or operation uses material or immaterial human input, if the input is received before performance of the process or operation. Human input is deemed to be material if such input influences how the process or operation will be performed. Human input that consents to the performance of the process or operation is not deemed to be “material”. 
         [0021]    The term “computer-readable medium” as used herein refers to any tangible storage that participates in providing instructions to a processor for execution. Such a medium may take many forms, including but not limited to, non-volatile media, volatile media, and transmission media. Non-volatile media includes, for example, NVRAM, or magnetic or optical disks. Volatile media includes dynamic memory, such as main memory. Common forms of computer-readable media include, for example, a floppy disk, a flexible disk, hard disk, magnetic tape, or any other magnetic medium, magneto-optical medium, a CD-ROM, any other optical medium, punch cards, paper tape, any other physical medium with patterns of holes, a RAM, a PROM, and EPROM, a FLASH-EPROM, a solid state medium like a memory card, any other memory chip or cartridge, or any other medium from which a computer can read. When the computer-readable media is configured as a database, it is to be understood that the database may be any type of database, such as relational, hierarchical, object-oriented, and/or the like. Accordingly, the disclosure is considered to include a tangible storage medium and prior art-recognized equivalents and successor media, in which the software implementations of the present disclosure are stored. 
         [0022]    The terms “determine”, “calculate”, and “compute,” and variations thereof, as used herein, are used interchangeably and include any type of methodology, process, mathematical operation or technique. 
         [0023]    The term “module” as used herein refers to any known or later developed hardware, software, firmware, artificial intelligence, fuzzy logic, or combination of hardware and software that is capable of performing the functionality associated with that element. Also, while the disclosure is described in terms of exemplary embodiments, it should be appreciated that individual aspects of the disclosure can be separately claimed. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0024]    The present disclosure is described in conjunction with the appended figures: 
           [0025]      FIG. 1  is a block diagram of a communication system in accordance with embodiments of the present disclosure; 
           [0026]      FIG. 2  is a diagram depicting a first communication flow in accordance with embodiments of the present disclosure; 
           [0027]      FIG. 3  is a diagram depicting a second communication flow in accordance with embodiments of the present disclosure; 
           [0028]      FIG. 4  is a flow diagram depicting a first communication method in accordance with embodiments of the present disclosure; and 
           [0029]      FIG. 5  is a flow diagram depicting a second communication method in accordance with embodiments of the present disclosure. 
       
    
    
     DETAILED DESCRIPTION 
       [0030]    The ensuing description provides embodiments only, and is not intended to limit the scope, applicability, or configuration of the claims. Rather, the ensuing description will provide those skilled in the art with an enabling description for implementing the embodiments. It being understood that various changes may be made in the function and arrangement of elements without departing from the spirit and scope of the appended claims. 
         [0031]      FIG. 1  depicts a communication system  100  according to an embodiment of the present disclosure. The communication system  100  may include an enterprise network  104  that is in communication, via a (typically untrusted or unsecure or public) communication network  108 , with one or more external communication devices  112 . The external communication devices  112  are generally referred to as “external” because they are either not under the direct control of the enterprise administering the enterprise network  104  or have a decreased level of trust with the enterprise network  104  as compared with communication devices  136  that are within the enterprise network  104 . Exemplary types of external communication devices  112  include, without limitation, cellular phones, smartphones, laptops, Personal Computers (PCs), Personal Digital Assistants (PDAs), digital phones, analog phones, and the like. 
         [0032]    The communication network  108  may be packet-switched and/or circuit-switched. An illustrative communication network  108  includes, without limitation, a Wide Area Network (WAN), such as the Internet, a Public Switched Telephone Network (PSTN), a Plain Old Telephone Service (POTS) network, a cellular communications network, an IP Multimedia Subsystem (IMS) network, a SIP network, a Voice over IP (VoIP) network, or combinations thereof. In one configuration, the communication network  108  is a public network supporting the TCP/IP suite of protocols. 
         [0033]    The enterprise network  104  may include a boundary device  116 , a communication server  120  including a session monitoring module  124  and a GSID module  128 , one or more internal communication devices  136 , a conference service  132 , one or more other servers  140 , and an enterprise database  144 , all of which are interconnected by a (trusted or secure or private) Local Area Network (LAN)  148 . Some or all of the functions depicted in  FIG. 1  may be co-hosted and/or co-resident on a single server. The depiction of components in  FIG. 1  is generally intended to be a logical depiction of the components of the system  100 . It should be appreciated that an enterprise network  104  may comprise multiple LANs  148  connected via a WAN, such as the communication network  108 . A single enterprise communication network  104  is depicted and described herein for ease of understanding and simplicity and in no way is intended to limit embodiments of the present invention to a single enterprise network  104 . 
         [0034]    The LAN  148  can be secured from intrusion by untrusted parties by a gateway and/or firewall located between the LAN  148  and communication network  108 . In some embodiments the boundary device  116  may include the functionality of the gateway and/or firewall. In some embodiments, a separate gateway or firewall may be provided between the boundary device  116  and the communication network  108 . 
         [0035]    The communications server  120  can include a Private Branch eXchange (PBX), an enterprise switch, an enterprise server, combinations thereof, or other type of telecommunications system switch or server. The communication server  120  is preferably configured to execute telecommunication functions such as the suite of applications made available via Avaya Aura™ platform of Avaya, Inc., including Communication Manager™, Avaya Aura Communication Manager™, Avaya IP Office™, Communication Manager Branch™, Session Manager™, System Manager™, MultiVantage Express™, and combinations thereof. 
         [0036]    Although only a single communications server  120  is depicted in  FIG. 1 , two or more communications servers  120  may be provided in a single enterprise network  104  or across multiple separate LANs  148  owned and operated by a single enterprise, but separated by communication network  108 . In configurations where an enterprise or an enterprise network  104  includes two or more communications servers  120 , each server  120  may comprise similar functionality, but may be provisioned for providing its features to only a subset of all enterprise users. In particular, a first communications server  120  may be authoritative for and service a first subset of enterprise users whereas a second communications server  120  may be authoritative for and service a second subset of enterprise users, where the first and second subsets of users generally do not share a common user. Accordingly, in some embodiments, the network boundary device  116  may be provided with a table or set of tables that comprise the information which maps a user to their authoritative communication server  120 . 
         [0037]    Additionally, multiple servers  120  can support a common user community. For example, in geo-redundant and other applications where users aren&#39;t necessarily bound to a single application server, there may be a cluster of equivalent servers where a user can be serviced by any server in the cluster. 
         [0038]    In accordance with at least some embodiments of the present invention, the mapping of user identities within a communication request does not necessarily have to occur at the network boundary device  116 . For instance, the mapping between an authoritative server and a user may occur “behind” the network boundary device  116  within the enterprise network  104 . In some embodiments, the network boundary device may include functionality similar to a Session Border Controller (SBC), a firewall, gateway, or any other device that provides security and/or translation capabilities. 
         [0039]    In some embodiments, network boundary device  116  is responsible for initially routing communications within the enterprise network  104  to the communications server  120  responsible for servicing a particular user involved in the communication. For example, if a first enterprise user is being called by an external communication device  112 , then the network boundary device  116  may initially receive the inbound call, determine that the call is directed toward the first enterprise user, identify the authoritative communications server  120  for the first enterprise user, and route the inbound call to the authoritative communications server  120 . Likewise, communications between internal enterprise users (e.g., internal communication devices  136 ) may first be serviced by the originating user&#39;s authoritative communications server  120  during the origination phase of communications set-up. After the origination phase is complete, the authoritative communications server  120  of the terminating (or called) user may be invoked to complete the termination phase of communications set-up. In some embodiments, the communications server  120  for the originating and terminating user may be the same, but this is not necessarily required. In situations where more than two enterprise users are involved in a communication session, authoritative communications servers  120  for each of the involved users may be employed without departing from the scope of the present invention. Additionally, the authoritative communications servers  120  for each user may be in the same enterprise network  104  or in different enterprise networks  104 , which are owned by a common enterprise but are separated by the communication network  108 . 
         [0040]    Each communications server  120  may include a session monitoring module  124  and GSID module  128 . The session monitoring module  124  may comprise the ability to monitor exchanges made during a communication session to determine which, if any, seemingly separate communication sessions are actually combined and, therefore, should be associated with one another by the GSID module  128 . More specifically, the session monitoring module  124  may be configured to monitor media and/or control packets transmitted between communication devices or between the conference service  132  and a communication device. In particular, the session monitoring module  124  may be configured to analyze communications for one or more of a REFER-To header, INVITE-Join R-URI, INVITE-Replace R-URI, Contact header, Call-Info header, av-ouri parameter, attachments, and other proprietary headers and parameters of a message. If a message, message header, media packet, or the like is detected to include some indication that the analyzed communication session should be associated with another different communication session, the session monitoring module  124  can further analyze the message component that indicated the association to identify how to search for the associated communication session. 
         [0041]    After the session monitoring module  124  has successfully identified the other communication session with which the analyzed session should be associated, the session monitoring module  124  invokes the GSID module  128 . The GSID module  128  may be configured to adjust instruct any communication component (e.g., communication device  112 ,  136 , communication server  120 , conference service  132 , etc.) that is involved in one or both of the associated communication sessions to adjust message parameters or properties (e.g., message contents, message headers, parameters of message headers) to reflect the association between the two communication sessions. In some embodiments, the GSID module  128  may be configured to instruct the entities involved in the communication sessions to adjust a so-called GSID header or parameter of a GSID header (hereinafter referred to as a GSID for ease of discussion) so that the GSID of one communication session references both communication sessions. In other words, a modified GSID is created for both sessions that have been identified as being associated with one another. The modified GSID contained in a message identifies both the session with which the message is transmitted as well as the associated session. This modified GSID enables an interested party to create more detailed and accurate communication history logs and troubleshoot potential problems in the communication system  100 . 
         [0042]    The conference service  132  may provide conferencing abilities to various communication devices both within and external to the enterprise network  104 . While the communication devices  112 ,  136  may natively support some conferencing capabilities (e.g., having mixers capable of conferencing a small number of communication devices), the conference service  132  may comprise the ability to conference a larger number of communication devices in a conference. In some embodiments, the resources of the conference service  132  include, without limitation, one or more mixers, filters, etc. The conference service  132  can support communication sessions of any media type or multiple media types such as voice, video, web conferencing, combinations thereof, etc. 
         [0043]    The conference service  132  may be initially included in the communication session by having each participant of the communication session access a particular bridge or common meeting destination by entering a predetermined address (e.g., telephone number, URL, etc.) and then entering one or more pass-codes (e.g., host code, participant codes, etc.). Alternatively, or in addition, a communication session between two or more communication devices  112 ,  136  may be moved to the conference service  132  during the communication session in an ad-hoc fashion to support a greater number of communication devices or to support different media types during the conference. 
         [0044]    Advantageously, when a communication session is transferred mid-session to the conference service  132 , the session monitoring module  124  is capable of detecting the transfer and determining that the communication session at the conference service  132  is associated with the communication session that was established and transferred to the conference service  132 . Accordingly, the GSID module  128  is instructed to decorate one or more content-bearing portions of message transmitted during the communication session at the conference service  132  to reflect the session&#39;s association with the previous session. The decoration can occur by altering one or more values of a GSID in the communication session. 
         [0045]    The other servers  140  may comprise email servers, voicemail servers, calendaring servers, conferencing servers, presence servers, and other types of servers known to provide particular services to client devices. In some embodiments, the other servers  140  may also be considered application servers, which provide one or more applications for use in a communication session. 
         [0046]    The internal communication devices  136  can be similar or identical to the external communication devices  112 , except they are provisioned, and often owned, by the enterprise. Exemplary types of communication devices  112 ,  136  include, without limitation, any capable phone, softphone and/or digital telephone. Examples of suitable telephones include the 1600™, 2400™, 4600™, 5400™, 5600™, 9600™, 9620™, 9630™, 9640™, 9640G™, 9650™, and Quick Edition™ telephones, IP wireless telephones (such as Avaya Inc.&#39;s IP DECT™ phones), video phones (such as Avaya Inc.&#39;s Videophone™), and softphones of Avaya, Inc. 
         [0047]    The enterprise database  144  includes enterprise subscriber information, such as name, job title, electronic address information (e.g., telephone number, email address, instant messaging handle, direct dial extension, and the like), subscriber contact lists (e.g., contact name and electronic address information), other employee records, and the like. 
         [0048]    The various servers and components depicted in  FIG. 1  may be implemented separately (i.e., on different servers) or together (i.e., on a single server). In particular, two or more depicted components (e.g., communication server  120  and conference service  132 ) may be implemented on a single server without departing from the scope of the present invention. Thus, a single device may provide the functionality of several components depicted separately in  FIG. 1 . As another example, the boundary device  116  and communication server  120  may be implemented on a single device. 
         [0049]    With reference now to  FIG. 2 , a first communication flow will be described in accordance with embodiments of the present disclosure. The first communication flow begins with a first communication session  212  between a first communication device operated by a first user (e.g., Alice  204 ) and a second communication device operated by a second user (e.g., Bob  208 ). The first communication session  212  may have a first GSID (e.g., 0001) assigned thereto by the GSID module  128 . The first GSID may be included in one or more message transmitted during the first communication session  212 . Specifically, the first GSID may be included in any content-bearing portion or portion(s) of a message such as a header, sub-header, footer, payload, and combinations thereof. 
         [0050]    The communication flow continues when a first communication event  216  occurs. The first communication event  216  in this illustrative example includes Alice  204  establishing a connection with a third communication device operated by a third user (e.g., Carol  220 ). The communication session established between Alice  204  and Carol  220  may be considered a second communication session  224  and may, therefore, have a second GSID (e.g., 0002) assigned thereto. Similar to the first GSID, the second GSID may be carried or represented in one, some or all messages transmitted during the second communication session  224 . Furthermore, the second GSID may be assigned by the GSID module  128  of the communication server  120  upon detecting establishment of the second communication session  224 . 
         [0051]    At this point, Alice  204  may be in a position to conference Bob  208  and Carol  220  into a single conference via a second communication event  228 . It should be appreciated that the conferencing of Alice  204 , Bob  208 , and Carol  220  can be accomplished in a variety of ways. In some embodiments, the conferencing of the participants may occur locally (e.g., at one of the communication devices of the participants) or the conferencing may be facilitated by a conferencing service  132 . 
         [0052]    The occurrence of either the first or second communication events  216 ,  228  may be detected by the session monitoring module  124 . The first or second communication event  216 ,  228  may correspond to any transmission of information that indicates the first communication session  212  is associated with the second communication session  224 . 
         [0053]    The session monitoring module  124  may then invoke the GSID module  128 , which instructs one, some, or all of the communication devices and/or any conferencing service  132  involved in either communication session  212 ,  224  to generate a modified GSID. As an example, the GSID of the first communication session  212  may be modified to refer to the original GSID of the first communication session  212 , the original GSID of the second communication session  224 , as well as a reason why the first association has been made. In some embodiments, the reason information may correspond to a description of the communication event that triggered the session monitoring module  124  to invoke the GSID module  128 . In some embodiments, the reason information may correspond to a non-technical description of the association between the communication sessions (e.g., “conference event”). It should be appreciated that other reasons may be inserted in the modified GSID. It should also be appreciated that the reason information does not necessarily need to be included in the modified GSID. Rather, the modified GSID may simply include the identification of the GSIDs originally assigned to each communication session (e.g., 0001+0002). 
         [0054]    Referring now to  FIG. 3 , a second communication flow will be described in accordance with embodiments of the present disclosure. The second communication flow begins with a first communication session  312  between a first communication device operated by a first user (e.g., Alice  304 ) and a second communication device operated by a second user (e.g., Bob  308 ). The first communication session  312  may have a first GSID (e.g., 0001) assigned thereto by the GSID module  128 . The first GSID may be included in one or more message transmitted during the first communication session  312 . Specifically, the first GSID may be included in any content-bearing portion or portion(s) of a message such as a header, sub-header, footer, payload, and combinations thereof. 
         [0055]    The communication flow continues when a first communication event  316  occurs. The first communication event  316  in this illustrative example includes Alice  304  establishing a connection with a third communication device operated by a third user (e.g., Carol  320 ). The communication session established between Alice  304  and Carol  320  may be considered a second communication session  324  and may, therefore, have a second GSID (e.g., 0002) assigned thereto. Similar to the first GSID, the second GSID may be carried or represented in one, some or all messages transmitted during the second communication session  324 . Furthermore, the second GSID may be assigned by the GSID module  128  of the communication server  120  upon detecting establishment of the second communication session  324 . 
         [0056]    At this point, Alice  304  may be in a position to transfer Bob  308  to Carol  320  (or vice versa) via a second communication event  328 . It should be appreciated that the transfer event may be a single event or multiple events without departing from the scope of the present disclosure. The occurrence of either the first or second communication events  316 ,  328  may be detected by the session monitoring module  124 . The first or second communication event  316 ,  328  may correspond to any transmission of information that indicates the association of the third communication session  332  with one or both of the first and second communication sessions  312 ,  324 . 
         [0057]    The connection between Bob  308  and Carol  320  may be viewed as a third communication session  332  and, therefore, may have a third GSID assigned thereto by the GSID module  128 . The third GSID may correspond to a third number that is substantially unique among other communication sessions (e.g., 0003) or the third GSID may be a combination of the first and second GSID (e.g., 0002+0001). Furthermore, the third GSID may comprise reason information that describes the association of the third communication session  332  with one or both of the first and second communication sessions  312 ,  324 . 
         [0058]    As can be seen in  FIG. 3 , the associations between the first communication session  312  and second communication session  324  may also be reflected in the GSIDs of those sessions. These updated GSIDs may be maintained in connection with the first and/or second communication session. 
         [0059]    A third communication event or series of events  336  may then occur whereby the sessions between Alice  304  and Bob  308  and Alice  304  and Carol  320  are dropped. At this point, the only communication session remaining is the third communication session  332  between Bob  308  and Carol  320 . 
         [0060]    Referring now to  FIG. 4 , a first communication method will be described in accordance with embodiments of the present disclosure. The method begins when activity regarding a first session is detected at the communication server  120  (step  404 ). The communication server  120  may also be configured to determine the type or nature of activity that was detected with respect to the first session (step  408 ). In particular, the communication server  120  may be configured to determine whether the detected activity corresponds to the detection of a new session (e.g., either the first session is a new session or a new session has been detected in association with the first session) or the detection of a session ending (e.g., either the first session has ended or a session associated with the first session has ended). 
         [0061]    If the detected activity corresponds to a session-ending activity, then the GSID information associated with the first communication session (and any other associated session) can be logged or otherwise stored in a communication database so that it is available at a later time if needed (step  412 ). In some embodiments, the GSID information can be stored in the enterprise database  144  or as call history information for one, some, or all of the participants involved in the first communication session or its associated communication session. 
         [0062]    If the detected activity corresponds to a session-beginning activity, then the new communication session (e.g., either the first communication session or an associated communication session) has a GSID assigned thereto. 
         [0063]    In some embodiments, the communication server  120  is configured to monitor communications within the communication system  100  and specifically within the enterprise network  104  to determine if the first session is associated with another session by detecting one or more indicators within the first session or within other sessions that refer to the first session to show the first session is associated with the previously-established session. Alternatively, or in addition, the search for associated sessions may occur after the first session is established. Specifically, the session monitoring module  124  may analyze messages exchanged during the first communication session and during subsequent communication sessions to determine if any later-established communication session should be associated with the first communication session. Accordingly, although step  408  depicts the detection of a “new” session, it may be the case that the detected session was already in progress prior to the first communication session, but the association with the first communication session is what makes the associated communication session appear “new” with respect to the first communication session. 
         [0064]    If at step  408  the first session is determined to be associated with another communication session, then the method continues with the session monitoring module  124  invoking the GSID module  128  to determine the nature of the association between the first communication session and the associated session (step  416 ). The GSID module  128  then instructs one or more devices involved in the first session and/or associated session to update their GSID information to reflect the association between the first session and the associated session (step  420 ). This can be accomplished in a variety of ways and the modification of GSID information can occur at any communication endpoint or intermediate device (e.g., server, switch, router, etc.) involved in the communication sessions. The steps depicted in connection with  FIG. 4  may be performed every time any activity regarding a session is detected or it may only be performed when certain predetermined activities are detected. 
         [0065]    With reference now to  FIG. 5 , another communication method will be described in accordance with embodiments of the present disclosure. The method begins when a first message from a first communication session is received (step  504 ). The first message may be received at the communication server  120 , a communication device  112 ,  136 , or any other device in the media or signaling path of the first communication session. Accordingly, the first message may correspond to a message containing media content (e.g., one or more of an RTP packet, http packet, VoIP packet, etc.), a message containing call-control content, or a message used to negotiate and establish the first communication session (e.g., a SIP message, an H.323 message, etc.). 
         [0066]    The method continues with the GSID module  128  assigning a first GSID to the first communication session (step  508 ). Once the first GSID is assigned to the first communication session, each transmission of information during the first communication session may either include or make reference to the first GSID. It is possible, however, to only having selected messages in the first communication session include or make reference to the first GSID. 
         [0067]    The first GSID, in some embodiments, is globally unique among GSIDs assigned by the GSID module  128 . In some embodiments, every GSID assigned by the GSID module  128  to a communication session is substantially unique. In some embodiments, every GSID assigned by the GSID module  128  at least unique within the universe of GSIDs assigned to communication sessions in the enterprise network  104 . 
         [0068]    The method continues when a second message from a second communication session is received (step  512 ). The second message may be received at the communication server  120 , a communication device  112 ,  136 , or any other device in the media or signaling path of the second communication session. In some embodiments, the device that receives the second message is the same device that receives the first message. In some embodiments, the device that receives both messages is a communication server. In some embodiments, different communication servers  120  may receive the messages. In some embodiments, the device that receives the second message is not in the media or signaling path of the first communication session. In some embodiments, the device that receives the second message is in at least one of the media and signaling path of the first communication session. 
         [0069]    Upon receiving the second message, the GSID module  128  is invoked to assign a second GSID to the second communication session (step  516 ). Once the second GSID is assigned to the second communication session, each transmission of information during the second communication session may either include or make reference to the second GSID. It is possible, however, to only having selected messages in the second communication session include or make reference to the second GSID. 
         [0070]    The method continues when it is determined that the first and second communication sessions are associated with one another (step  520 ). This determination may be made by the session monitoring module  124  either during the establishment of the second communication session or after the second communication session is already established. Furthermore, this determination may be made by analyzing message transmitted during the first session, messages transmitted during the second session, or a combination of messages transmitted during the first and second sessions. Further still, the first communication session does not necessarily have to use the same media type as the second communication session. For example, one session may be a voice-based session and the other session may be a web-based session. 
         [0071]    When the session monitoring module  124  has determined that the first and second sessions are associated, the method continues with the session monitoring module  124  invoking the GSID module  128  to alter the first and/or second GSID to describe the association between the first and second communication sessions (step  524 ). In some embodiments, the first GSID assigned to the first communication session may be altered to refer to the second GSID. This altered GSID can be referred to as an altered first GSID or a third GSID. In some embodiments, the second GSID assigned to the second communication session may be altered to refer to the first GSID. This altered GSID can be referred to as an altered second GSID, a third GSID (e.g., the same as the altered first GSID), or a fourth GSID. In some embodiments, one or both of the first and second GSID are altered to include reason information that describes why the first communication session was associated with the second communication session. 
         [0072]    It should be appreciated that while embodiments of the present disclosure have been described in connection with a particular communication system architecture, embodiments of the present disclosure are not so limited. In particular, those skilled in the communication arts will appreciate that some or all of the concepts described herein may be utilized in any communication system that has the need to identify or troubleshoot communication sessions, especially where the topology of such sessions is likely to be modified. 
         [0073]    Furthermore, in the foregoing description, for the purposes of illustration, methods were described in a particular order. It should be appreciated that in alternate embodiments, the methods may be performed in a different order than that described. It should also be appreciated that the methods described above may be performed by hardware components or may be embodied in sequences of machine-executable instructions, which may be used to cause a machine, such as a general-purpose or special-purpose processor (GPU or CPU) or logic circuits programmed with the instructions to perform the methods (FPGA). These machine-executable instructions may be stored on one or more machine readable mediums, such as CD-ROMs or other type of optical disks, floppy diskettes, ROMs, RAMs, EPROMs, EEPROMs, magnetic or optical cards, flash memory, or other types of machine-readable mediums suitable for storing electronic instructions. Alternatively, the methods may be performed by a combination of hardware and software. 
         [0074]    Specific details were given in the description to provide a thorough understanding of the embodiments. However, it will be understood by one of ordinary skill in the art that the embodiments may be practiced without these specific details. For example, circuits may be shown in block diagrams in order not to obscure the embodiments in unnecessary detail. In other instances, well-known circuits, processes, algorithms, structures, and techniques may be shown without unnecessary detail in order to avoid obscuring the embodiments. 
         [0075]    Also, it is noted that the embodiments were described as a process which is depicted as a flowchart, a flow diagram, a data flow diagram, a structure diagram, or a block diagram. Although a flowchart may describe the operations as a sequential process, many of the operations can be performed in parallel or concurrently. In addition, the order of the operations may be re-arranged. A process is terminated when its operations are completed, but could have additional steps not included in the figure. A process may correspond to a method, a function, a procedure, a subroutine, a subprogram, etc. When a process corresponds to a function, its termination corresponds to a return of the function to the calling function or the main function. 
         [0076]    Furthermore, embodiments may be implemented by hardware, software, firmware, middleware, microcode, hardware description languages, or any combination thereof. When implemented in software, firmware, middleware or microcode, the program code or code segments to perform the necessary tasks may be stored in a machine readable medium such as storage medium. A processor(s) may perform the necessary tasks. A code segment may represent a procedure, a function, a subprogram, a program, a routine, a subroutine, a module, a software package, a class, or any combination of instructions, data structures, or program statements. A code segment may be coupled to another code segment or a hardware circuit by passing and/or receiving information, data, arguments, parameters, or memory contents. Information, arguments, parameters, data, etc. may be passed, forwarded, or transmitted via any suitable means including memory sharing, message passing, token passing, network transmission, etc. 
         [0077]    While illustrative embodiments of the disclosure have been described in detail herein, it is to be understood that the inventive concepts may be otherwise variously embodied and employed, and that the appended claims are intended to be construed to include such variations, except as limited by the prior art.