Abstract:
An exemplary embodiment of a method is implemented in a wireless network and is advantageous in that an undesired interim media channel link which would have been used in prior art systems is identified during call setup and avoided. In response to a call request in the wireless network for a call with a first user&#39;s wireless subscriber unit, a determination is made if one of a calling home node and a called home node of the first user&#39;s wireless subscriber unit should not be used as a node in the media channel such as due to the one node&#39;s remote location relative to the rest of the nodes in the media channel. A resulting media channel is established so that the one of the calling home node and the called home node is not part of a path of the media channel thereby minimizing the total distance and delay of the media path.

Description:
FIELD OF INVENTION 
     This invention relates to wireless mobile networks and more specifically to the communication path established between subscriber units through nodes of the network especially, but not limited to, when one of the calling and called wireless units is located away from its home location. 
     BACKGROUND 
     Wireless subscriber units (SUs) are supported by wireless networks located at various geographic locations. A subscriber of wireless services has his subscriber unit registered in a home network at a home location register (HLR) or its equivalent. When traveling the subscriber is served by another network that uses a signaling channel and a media channel to establish wireless communications. As used herein a “media channel” refers to the communication path over which user information is conveyed, which is contrasted with a signaling channel that carries command and control information associated with the setup, management and termination of a media channel. The subscriber&#39;s HLR keeps track of the current location of the subscriber unit and serves as an “anchor” point for the voice traffic with a wireless subscriber unit. When the subscriber is served by another remote network, the media channel will likely include one or more wireline links as part of the voice path to the subscriber&#39;s home HLR in addition to the wireless link that supports the subscriber&#39;s wireless subscriber unit. 
     However, this routing for a media channel is not efficient in some situations. Assume there is a disaster in the Los Angeles (LA) area, and some firefighters from New York City (NYC) travel to LA to help. A firefighter from NYC using a first wireless SU is currently located at the LA area, while a firefighter from LA uses a second SU. The HLR of the first SU is at NYC, while both the serving node for the first SU and the HLR of the second SU are at LA. The path for the media channel includes cross-country links between LA and NYC. Similarly, if the firefighter from LA calls the visiting firefighter from NYC, the same cross-country path links would occur. 
     SUMMARY OF THE INVENTION 
     I have recognized that it would be advantageous to better control of the media path routing so as to minimize undesired interim path links. To this end, the present invention minimizes the assignment of undesirable inter-node loops in the media path when a wireless subscriber is away from his home network. This is achieved by routing the media path without incorporating therein the subscriber&#39;s home node when it is determined that the wireless subscriber unit is away from its home network. Note, by way of contrast, that the subscriber&#39;s home node is conventionally assigned as one of the nodes in the media path by the prior art. In accordance with an aspect of the invention, the home node is eliminated as a requirement of the media path regardless of whether the subscriber originates the call, in which case the home node is termed a calling home node, or the subscriber receives the call, in which case the home node is termed a called home node. Advantageously the total length and delays associated with the media path for a subscriber away from his home network are reduced. 
     An exemplary embodiment of a method is implemented in a wireless network and is advantageous in that an undesired interim media channel link which would have been used in prior art systems is identified during call setup and avoided. More specifically, in response to a call request in the wireless network for a call with a first user&#39;s wireless subscriber unit, it is determined whether or not the home node of the first user&#39;s wireless subscriber unit, which may be a calling home node or a called home node, should not be used as a node in the media channel due to the node&#39;s remote location relative to the rest of the nodes in the media channel. When it is determined that the first user&#39;s home node should not be used, a media channel is established so that the home node is not part of the path of the media channel, thereby minimizing the total distance and delay of the media path. 
     In another embodiment, the home node of the first user can request that the home node of the other user on the call, i.e., its peer home node, be removed from the media path. 
     In a further embodiment, both the home nodes of both users can be removed from the media path and another node in the system, e.g., one of the serving nodes, can be requested to serve as the anchor point of the media traffic for the call. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an illustrative embodiment of the present invention of a call setup procedure where the calling home node is not part of the media channel. 
         FIG. 2  is similar to  FIG. 1  except that a request to bypass the calling home node is rejected. 
         FIG. 3  shows the resulting media channel when the calling home node is bypassed as per  FIG. 1 . 
         FIG. 4  shows an illustrative architecture and procedure in accordance with the present invention for the handoff of an existing call. 
         FIG. 5  shows an alternate illustrative architecture and procedure in accordance with the present invention for the handoff of an existing call. 
         FIG. 6  is an illustrative embodiment of the present invention of a call setup procedure where the called home node is not part of the media path. 
         FIG. 7  is an illustrative embodiment of the present invention of a call setup procedure where neither the calling nor called home nodes are part of the media path with the called serving node becoming the new anchor point for the media channel. 
         FIG. 8  is an illustrative embodiment of the present invention of a call setup procedure where neither the calling nor called home nodes are part of the media path with the anchor point being a system node other than a serving node. 
         FIG. 9  shows the resulting media channels when the calling and called home nodes are both bypassed as per  FIG. 8 . 
     
    
    
     DETAILED DESCRIPTION 
     Consider the situation where the calling home node is in one city, while all the other system nodes are at another city. The media path would be improved if the calling home is removed from, i.e., is not part of, the media path. The call signaling protocol in this example is based on Session Invitation Protocol (SIP), while the voice traffic is carried on the media channel through the use of Real Time Protocol (RTP). Per an embodiment of the present invention, the calling home node can signal a bypass request to the called home in the Setup message. In the same request, the calling home node could provide two network internet protocol (IP) addresses to the called home system. One address is the network address of the calling serving system, and this address would be used by the called home system if the bypass request is accepted. The other IP address is from the calling home node and is to be used if the bypass requested is rejected. If the called home accepts the request, the calling home node would forward the address from the called home node to the calling serving system so that the media communication channel will go directly between the called home node and the calling serving node, thereby bypassing the calling home node. Similarly, the called home node or both home calling and called nodes can be requested to be removed from the media path. If the request(s) is rejected, normal media channel routing would be established through each home node. 
     In the United States, the standard of public safety wireless network is the Association of Public Safety Communications Officials (APCO) Project 25 (P25) Systems whose specifications are the responsibility of the Telecommunications Industry Association (TIA), standard committee TR-8. Although an exemplary P25 system is described below and used as illustrative examples of embodiments of the present invention, other systems and signaling protocols can be constructed and/or used in accordance with the present invention. Embodiments of the present invention are especially, but not exclusively, suited for use with IP based connecting networks. The over-the-air interface protocol can be of any wireless technology. An example of such a wireless system is the radio frequency sub-system (RFSS) of a P25 system as specified by the TIA TSB 102 series of standards. 
     For a subscriber-to-subscriber call, the call signaling according to prior art methods would pass through all four entities, in the following order:
         The calling serving system (node): This is the system/node where wireless communications with the calling subscriber is currently supported.   The calling home system (node): This is the system where information on the calling subscriber is maintained. When a subscriber roams from a system to another, it will register with its home system. Because of this, the home system of a subscriber knows the current location of the subscriber.   The called home system (node): The same as the calling home system except it is for the called subscriber.   The called serving system (node): This is the system where the called subscriber is currently served by wireless communications.       

     As a subscriber can roam between systems, the calling and called serving systems may change during a call. The above definitions are logical designations in the sense that one physical system or one serving node could be home to both subscribers. 
     Media traffic, e.g., voice traffic, in general, also passes through the above mentioned nodes in prior art systems. As previously explained for certain call scenarios, the routes of the media traffic are not efficient or desirable. 
     Embodiments of the present invention provide enhancements to the call signaling procedure over the network so that the media channel can be improved. Specifically, some of the functional enhancements to the call signaling procedure provided by the embodiments of the present invention are:
         A home system, either calling or the called home system, can request itself to be removed from the media path. This type of request is referred to as “type 1 bypass request” or just “bypass request”.   A home system, either the calling or the called home system, can request its peer home node to be removed from the media path. This type of request is referred to as “type 2 bypass request”.   A home system can request another system, not necessarily one of the four systems/nodes that would typically be involved in the call, to be an “anchor point” for the media traffic. That is, traffic from the calling and called serving nodes will forward the traffic to a peer system/node for the duration of the call, where the peer node is not either the home calling node or the called home node. This type of request is referred to as “new anchor request”.       

     In all these requests, the recipient of the request in accordance with embodiments of the present invention can accept or reject the request. If the request is rejected, the call paths will proceed as a normal call. Also, when a system is by-passed (or removed) from the media path, the signaling path is unchanged, i.e., signaling messages still pass through the normal system nodes in accordance with the embodiments of the present invention. One of the factors on whether to request a bypass is the distance among the nodes in the media path, i.e., whether one or more of the nodes is not proximate to the other nodes in the media path. As used herein, one node being proximate to another node means that the one node is less than a predetermined distance from the other node. 
     Terminology 
     For most wide area call signaling protocols, the following functional messages are supported in call set-up:
         Setup: This is the message sent by an entity to set up a call between itself and its peer (the entity receiving this message).   Connect: This is the message sent upon recipient of the Setup message indicating the call has been set up successfully.   Confirm: This is the message sent by a end-point in response to the Connect message, indicating it has received the Connect message.       

     In systems based on the SIP protocol, the above three messages are implemented as the INVITE, 200 OK, and ACK messages. In many instances, a call may take time to process; in this case, the recipient of the Setup message may response with a Progress message before sending the Connect message. In an embodiment based on the SIP protocol, this consists of the various 1xx provisional response messages. The Disconnect message and its acknowledgement are used to tear down a call. In SIP protocol systems, this is the BYE and the corresponding 200 OK messages. 
     A call may be modified during the duration of the call; this is accomplished through the Modify message. The Connect message can be used acknowledge the modification. In an SIP system, mid-call modification is accomplished by sending the INVITE message again; these INVITE messages are referred to as re-INVITEs. 
     All call signaling messages can carry many parameters. As described below for embodiments of the present invention, the signaling messages can carry the following parameters:
         Request: This parameter is used to indicate the sender of the message is requesting a type-1 bypass, a type-2 bypass, or new-anchor request.   Request acknowledgement: This parameter is used to indicate whether a request is accepted or rejected.   Normal Address: This is the network address where media traffic will be sent assuming the call proceeds as a normal call (i.e. normal path allocation). This is the address that will be used if a request is rejected.   Bypass Address: This is the network address where media traffic will be sent if the request is accepted.   New anchor address: This is the network address of the new anchor point.       

     For an IP network, a network address will be an IP address of a specified node together with a corresponding UDP port number. Although a system may use the same IP address for all traffic, different UDP port numbers could be assigned for different traffic segments of the same call. 
     In embodiments of the present invention based on the SIP protocol, request, request acknowledgement, bypass address, and new anchor address are new parameters and can be encoded in a number of ways (e.g., in the message body of the SIP message). The normal address is usually encoded in the SDP portion of the SIP messages. 
     For over the air interfaces, there are four basic functional messages for call set up:
         Outgoing call request   Incoming call request   Incoming call answered   Outgoing call connected       

     In the illustrative embodiments where the air interface adheres to the P25 trunked system specification, the above four messages are: UU_V_REQ, UU_V_ANS_REQ, UU_V_ANS_REP, and UU_V_CH_GRANT, respectively. 
     At a serving system, over the air interface signaling messages will be mapped to call signaling messages over the wide area network:
         The outgoing call request over the air interface would be mapped to a outgoing Setup message over the wide area network.   An incoming Setup message from the wide area network will be mapped to an incoming call message over the air interface.   An outgoing call message over the air interface will be mapped to a outgoing Connect message over the wide area network.   An incoming Connect message from the wide area network will be mapped to a outgoing call connected message over the air interface.       

     In subsequent exemplary descriptions, it is assumed that, at the serving RFSS, outgoing SIP messages are triggered by messages from the air interface, and incoming SIP messages trigger messages to the air interface. 
     Type 1 Bypass (Bypassing the Calling Home) 
     Referring to  FIG. 1 , consider the case when a firefighter from NYC visiting LA calls another firefighter whose home is at LA. In this case,
         The calling serving system  210 , called home system  230 , and the called serving system  240  are at LA, with network address pools A, C and D, respectively.   The calling home system  220  is at NYC with network address pool B.       

     Under prior art call processing, the media path is not optimal as it goes from LA to NYC and then back from NYC to LA, as discussed before; see  FIG. 4 . One way to improve the route of the media path is to have the calling system  220  identify the locations of the SUs and to initiate a type-1 bypass request to attempt to remove itself from the media path. The procedure for a successful request is illustrated in  FIG. 1 .
         1) User  101  (visiting NYC firefighter) initiates the call with an “outgoing call request” over the air interface (message  1  in  FIG. 1 ). The calling serving system  210  converts this request to a Setup message (message  2 ) and sends this message to the calling home system  220 . The Setup message would contain the normal address (A 1 ) from  210 . So far, the call proceeds as a normal, i.e., prior art, call.   2) System  220  determines that user  101  is at system  210  which is located at LA. It also determines that the home of user  102 , the called party, is system  230  also located at LA. Based on this information, RFSS  220  decides that it is better if RFSS  210  would send the media traffic to RFSS  230  directly, bypassing system  220 . Therefore, system  220  will forward the Setup message (message  3 ) to the called home system  230  with the normal call information, but with the following additional information:
           a. A type-1 bypass request indicating that it wants to be removed from the media path.   b. A normal network address, to be used if the bypass request is rejected. This address (B 1 ) will be for itself.   c. The bypass network address to be used if the request is accepted. This address is encoded with the address in the Setup message from system  210  (address=A 1 ).   
           3) Upon receipt of the above Setup message, system  230  will decide whether to reject the request or not. In either case, it will forward the Setup message to system  240 , the called serving system. The call will proceed as a normal call (messages  4 ,  5 ,  6 , and  7 ) until system  230  receives the Connect message (message  7 ) from system  240 .   4) Assuming that system  230  accepts the type-1 bypass request, it will forward the Connect message (message  8 ) to  220  with the additional information that the bypass request is accepted.   5) System  220 , upon receipt of the above Connect message, would forward the Connect message to system  210 . In this message, the normal address location is encoded with the address provided by system  230  (address C 2 ), as opposed to using an address from itself (address B 2 ) as would have occurred in normal prior art call setup.   6) The rest of the call signaling (messages  9 ,  10 ,  11 ,  12  and  13 ) proceeds as a normal call.       

     After completion of a successful bypass request, the NYC system  220  will not be in the media path as shown by the packet flow at the bottom of  FIG. 1  but system  220  will remain in the signaling path. The media and signaling paths for this bypass of system  220  are illustrated in  FIG. 3 . 
     Referring to  FIG. 2 , the called home system  230  may elect to reject the bypass request from system  220  because of a number of reasons. For example, user  102  may be at NYC at this time and it would be better if system  230  was removed from the media path rather than system  220 . In this case,
         System  230  would indicate to system  220  in message  8  that it rejects the bypass request.   System  220  would use an address from itself (B 2 ) instead of the one from system  230  (C 2 ) in message  9 .       

     Basically the call proceeds as a normal call setup following the bypass rejection since all four of the nodes shown in  FIG. 2  will be in the media channel path; see the packet flows on the bottom of  FIG. 2 . 
     Roaming During Existing Call When the Calling Home System is Bypassed 
     Assume that the above described type-1 bypass request was made and accepted, i.e., the calling home system  220  in NYC is bypassed. When user  102  roams during an existing call, the procedure will be the same as roaming for normal prior art call as system  230  is the home of user  102  and it will know where user  102  is located and can handle roaming requests by  102  in the normal manner. However, if user  101  roams during an existing call, the procedure for handling roaming will be different than roaming procedures for normal prior art call, as the calling home system  220  is not part of the media path (although it is still in the call signaling path). 
     In a first method for supporting roaming as shown in  FIG. 4 , the calling home system  220  sends a notification to system  230  of the called home system, the anchor point of the media traffic for the call, that user  101  has roamed (during an existing call) to system  310 . Upon this notification, system  230  establishes a connection for media traffic to system  310 . Specifically, the procedure is as follows:
         1) Once system  220  determines that user  101  has roamed to system  310  (through the registration process), it will send a “Roamed” notification to system  230 . This notification would contain the identity of the system  310  and user  101 .   2) System  230  then sends a Setup message to system  310  using the current address (C 2 ) as the normal address. This message will go through system  220  as system  220  remains in the signaling path.   3) Upon the receipt of the Setup message, system  310  responds with a Connect message, which would contain its normal address (E 1 ) for this call. This message will go through system  220 .   4) Upon the receipt of the Connect message, system  230  then responds with an Confirm message, completing the transaction. This message will go through system  220 .   5) At the same time, system  230  will send a Disconnect message to system  210 , the previous serving system for user  101 , terminating the media flow to/from system  210 . This message will go through system  220 .       

     At the end of the above process, the media flow is between system  310  and system  230  using address pair (E 1 , C 2 ). This method for handling roaming is known as the “notification method”. Assuming the protocol is SIP based, there are a number of ways to send the “Roamed” notification:
         Use the NOTIFY message   Use the REFER message   Use the INFO message       

       FIG. 5  illustrates another method for supporting roaming as follows:
         1) Once system  220  determines that user  101  has roamed to system  310  (through the registration process), it will send a Setup message to system  310 . The address in this message will be encoded with the current address used by the system  230  in receiving media traffic from user  101  (address C 2 ).   2) Upon receipt of this Setup message, system  310  will respond with a Connect message. Encoded in this message is the address to be used by system  310  for this call (address=E 1 ).   3) Upon the receipt of this message, system  220  will first respond with a Confirm message to system  310 .   4) At the same time, system  220  will send a Modify message to system  230 , informing that the network address for media traffic of its peer has changed from system  210  to system  310  (from A 1  to E 1 ).   5) System  230  responds with a Connect command acknowledging the modification.   6) System  220  responds with a Confirm message completing the process.       
     Other variations are possible to support such roaming. In general, the method that is simpler and requires fewer messages will be the preferred method, unless other factors dictate another choice. 
     Type 1 Bypass Request (Bypassing the Called Home) 
     Referring to  FIG. 6 , assume that a local firefighter using phone  101  at LA calls the visiting firefighter&#39;s phone  102  from NYC (but currently at LA). Thus systems  210 ,  220 , and  240  are at LA, while system  230  is at NYC. The procedure is as follows:
         1) User  101  initiates the call and sends an “outgoing call” message over the air interface to its serving system  210 .   2) System  210  converts the “outgoing call” message to a Setup message and sends it system  220 . This message will contain an address (A 1 ) from system  210 .   3) System  220  forwards the Setup message to system  230 . The message will contain an address (B 1 ) from system  220 .   4) Upon the receipt the Setup message from  220 , system  230  as the home system of user  102  would know that the calling serving system  220 , the calling home system  230 , and the current serving system for user  102  (system  240 ) are all are LA, while system  230  is at NYC. Based on this information, system  230  decides that a better route for the media traffic can be obtained if it removes itself from the media path. Thus, system  230  initiates a bypass procedure to do so. It will first forward the Setup message  4  to system  240 . However, this Setup message will not contain any address information as would normally be included. This is because, at this time, system  230  does not know whether its bypass request will be accepted or not. The address used will depend on this decision.   5) Upon receipt of the Setup message from system  230 , system  240  will sends an incoming call message to user  101  over the air interface.   6) Assuming that user  102  answers the call, the end-point equipment would send an incoming call answered message back to system  240 .   7) Upon receipt of the incoming call answered message, system  240  sends a Connect message to system  230 . This message will contain an address (D 2 ) from system  240 .   8) System  240  forwards the Connect message to the calling home system  220  containing the following information:
           A type-1 bypass request indicating that system  230  wants to remove itself from the media path.   A normal address for itself (C 2 ) to be used by system  220  if the by-pass request is rejected; and the bypass address (D 2 ) to be used if the bypass request is accepted; see message  8 .   
           9) System  220  will forward the Connect message to system  210 . This message would contain an address from system  220  (B 2 ).   10) Upon receipt of the Connect message from system  220 , system  210  will generate an out-going call connected message to user  101  over the air interface.   11) At the same time, system  210  sends a Confirm message  11  back to system  220 .   12) System  220  forwards the Confirm message  12  to system  230  with an indication whether the bypass request is accepted or rejected.   13) System  230  forwards the Confirm message  13  to system  240 . If the request is accepted, this message would contain the address provided by system  220  (B 1 ). If the request is rejected, it would contain an address from system  230  itself (C 1 ).       

     Roaming When the Called Home System is Bypassed 
     The roaming procedure when the called home is bypassed can be the same procedure as described above as when the calling home is bypassed. 
     Bypass of Both Home Nodes: (a New Anchor Point to be Established) 
     Referring to  FIG. 7 , assume that two NYC firefighters are both currently visiting LA and one using phone  101  calls the other with phone  102 . In this case, both home systems  220  and  230  are at NYC while both users and serving systems  210  and  240  are at LA. For best efficiency in media traffic flow, the media path should bypass both home systems and a new anchor point for media traffic at LA should be used. 
     First, note that home system  230  is the first system to be able to determine that both serving systems  210  and  240  are at LA; that is, system  220  during the initial call setup will not have access to information about the location of the called serving system. System  230  can determine the serving system for user  101  is system  210  from the Setup message (it contains the origin of the call). System  230  can determine that user  102  is at serving system  240  because system  230  is the home of user  102 . Therefore, system  230 , the called home, would make the decision that the media traffic should bypass both home systems. The process can be implemented as two parts:
         First, system  230  would request another system at LA to serve as a new anchor point for the media traffic. A good candidate would be called serving system  240 , but this is not the only choice that could be made.   Then, system  230  will request system  220  to remove itself from the media path. This is type-2 bypass request, where a home system requests its peer to remove itself from the media path.       

     If both requests are successful, then system  240  in LA will be the only anchor point in the media path and an optimal media channel route involving only nodes in LA is achieved. It is easier for a node to remove itself from a media path than to become an anchor point. Therefore, system  230  would seek a new anchor point first, and ascertain its success before sending the type-2 bypass request to system  220 . 
     This procedure is illustrated in  FIG. 7  as:
         1) User  101  initiates the call and sends an outgoing call message over the air interface to its serving system  210 .   2) System  210  converts the outgoing call message to a Setup message and sends it system  220 . This message will contain an address (A 1 ) from system  210 .   3) System  220  forwards the Setup message to system  230 . The message will contain an address (B 1 ) from system  220 .   4) Upon the receipt the Setup message from  220 , system  230  as the home system of user  102 , would know that the calling serving system  220  and the current serving system  240  for user  102  are both at LA, while both home systems are at NYC. Therefore, it decides that a better route for the media traffic can be obtained if both home nodes are removed/bypassed from the media path. First system  230  will initiate the procedure requesting that system  240  become a new anchor point. If successful system  230  will remove itself from the media path. It will first forward the Setup message to system  240 . This Setup message would contain the normal address for media traffic from system  230  as well as the request that system  240  to become the new anchor point for media traffic. The normal address is included in the event that system  240  rejects the request to be an anchor point.   5) Upon receipt of the Setup message from system  230 , system  240  sends an incoming call message to user  102  over the air interface. It would also need to decide whether it will serve as the new anchor point.   6) Assuming that user  102  answers the call, the end-point equipment would send an incoming call answered message back to system  240 .   7) Upon receipt of the incoming call answered message, system  240  sends a Connect message  7  to system  230 . This message will contain an address (D 2 ) from system  240  as well as its decision on the new anchor point request. It could accept or reject the request.  FIG. 7  illustrates the case that the request is accepted.   8) System  230  forwards the Connect message  8  to system  220  containing the following information, if the anchor request is accepted:
           A type-2 bypass request indicating that system  230  desires that system  220 , the calling home, be removed from the media path.   The address from system  240  (D 2 ).   The identity of the new anchor point, system  240 .   
           9) System  220  will forward the Connect message  9  to system  210 . This message would contain the address from system  240  (D 2 ).   10) Upon receipt of the Connect message from system  220 , system  210  will generate an out-going call connected message to user  101  over the air interface.   11) At the same time, system  210  sends a Confirm message  11  back to system  220 .   12) System  220  forwards the Confirm message  12  back with an indication whether the type-2 bypass request is accepted or rejected. In this case, it is accepted.   13) System  230  forwards the Confirm message  13  to system  240 .       

     If the new-anchor request is rejected (at step  7 ), system  230  would not invoke the type-2 bypass request and the call request would proceed as normal. 
     Referring to  FIG. 8 , instead of system  240  becoming a new anchor point, another system  320 , preferably in LA, could be selected as the new anchor point. This procedure is an extension of the above procedure and its implementation should be apparent based on the above explanation of  FIG. 7  and the signal flow as shown in  FIG. 8 . 
     Once the new system at LA becomes the new anchor point and with the both home systems removed from the media path, the media path is as illustrated in  FIG. 9  assuming that a new node  320  in LA serves as the new anchor point for media traffic as per  FIG. 12   a.  If node  240  became the new anchor point as per  FIG. 7 , the functionality of  320  would be transferred to  240  and node  320  would be removed from  FIG. 9 . 
     Embodiments of the present invention provide innovative methods that improve the paths selected for media traffic including:
         A home system can request itself to be removed from the media path. The home system can be either the calling home or the called home.   A home system can request its peer home system to be removed from the media path.   A home system can request another system to be the anchor point of the media traffic for a call.       

     The above exemplary systems/nodes may each consist of a similar architecture. That is, the architecture may consist of a microprocessor supported by read-only memory, random access memory, nonvolatile data storage, and an input/output module that supports the transmission and reception of data between the node and external devices/environments. The microprocessor operates under the control of stored program instructions that implement the signaling, media traffic control and decision-making functions as described in accordance with the illustrative embodiments. 
     Various modifications, substitutions and alterations of the illustrative embodiments may be made by those skilled in the art without departing from the scope of the present invention. For example, signaling and media communication paths may be carried by a variety of communication protocols in addition to or other than Internet Protocol. It is not necessary for both end-users to be supported by a wireless network, i.e., one end-user may be supported by a traditional wireline telephone (or other non-wireless system) and the other end-user supported by a wireless communication network. Even a single wireless end-user can benefit such as where the wireless user&#39;s serving node is located in a remote network or a substantial distance from the home node of the wireless end-user. The decision on whether to request a bypass and/or accept a request for a bypass can be based on a variety and/or combination of factors, including but not limited to, geographical distances among nodes in the media traffic path, city/state location of the nodes, data transit times between nodes, loading of the respective nodes, end-user provided information or data, etc. Where the location of the nodes is a factor, the decision can be based on the length of the media channel, i.e., whether the bypassing of a node would reduce the length of the media channel by more than a predetermined amount and/or percentage. For example, the decision to bypass a node could be made if doing so would reduce the total length of the media channel and/or total delay of media traveling over the channel by at least 30%. This would prevent incurring the overhead signaling associated with implementing the bypass if only a relatively small performance improvement would be obtained. Both the normal address and a bypass address can be transmitted in the same communication where a bypass request is made so that the decision making node will be have the address to be utilized regardless of whether the bypass request is accepted or not. 
     Although the embodiments focus on traffic route improvements, the procedures can be used to achieve other objectives based on factors related to the objective. For example, if a system is at or near its capacity limit in handling media traffic, the described procedures can be used to off-load (bypass) media traffic from such a system to another system. 
     The above embodiments are merely illustrative examples and are not to be construed as limiting the scope of the present invention as defined by the attached claims.