The challenged claims all depend from Claim 1, which relates to a method of enabling media bypass for a media gateway in a telecommunications network. More particularly, a plurality of media gateways provide a signaling path via which signaling information is transferred for setup of a communication session between two endpoints, and provide a media path via which media data is transferred between the endpoints during the communication session.
Claim 1 requires a media gateway to receive an inbound communication session setup request message and transmit an outbound communication session setup request message, which outbound message includes preceding device connectivity data.
The preceding device connectivity data of Claim 1 indicates at least one media connectivity setting for the preceding device. The media connectivity
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setting identifies one or more other devices to which the preceding device is configured to be connectable in a media path, to enable bypass of the media gateway in the media path. As discussed above, the media connectivity setting “describes the parts, domains or regions of telecommunications network 1 to which the device does have media connectivity.” Id. at 11:30-37 and Claim 15.
Ejzak ’270 discloses all features of Claim 1 of the ’640 Patent including Limitation [1a], “[a] method of enabling media bypass for a media gateway in a telecommunications network.” Ex. 1104 at ¶¶ 53-58, 143-147. For example, Ejzak ’270 discloses a method that allows “Session Initiation Protocol (SIP) based networks to bypass one or more border gateways that would otherwise be included in a media path.” Ex. 1103 at ¶ 0002. Ejzak ’270 also discloses that a call configuration between IP endpoints includes SIP signaling communicated between two endpoints via at least one application layer gateway (ALG), and Real time Transport Protocol (RTP) multimedia flow communicated between the user agent endpoints via the border gateways. Ex. 1103 at ¶ 0042; see also Ex. 1104 at ¶¶ 143-147.
Ejzak ’270 discloses Limitation [1b] “receiving, at said media gateway, an inbound communication session setup request message…” Ex. 1104 at ¶¶ 143, 148-151. Specifically, Ejzak ’270 discloses an ALG receiving an SDP offer, which is a message requesting setup of a communications session. Ex. 1103 at Abstract;
¶¶ 0057, 0069; see also Ex. 1104 at ¶¶ 143, 148-151. Ejzak ’270 also discloses Limitation [1c], “transmitting, from said media gateway, an outbound communication session setup request message…” Ex. 1104 at ¶¶ 143, 152-155. After the ALG receives and modifies the SDP offer as detailed above, the ALG may then forward the modified SDP offer. Ex. 1103 at ¶¶ 0073, 0075, 0077-79; Fig. 2, box 221 and Ex. 1104 at ¶¶ 143, 152-155.
Ejzak ’270 discloses Limitation [1d], “including preceding device connectivity data in said outbound communication session setup request message…” Ex. 1104 at ¶¶ 143, 156-164. Specifically, Ejzak ’270 discloses including IP realm information about prior BGs in the traversed-realm SDP extension of an outbound SDP offer. Id. at ¶ 157. After receiving an SDP offer, the ALG of Ejzak ’270 determines whether any IP realm instance in the traversed- realm extension field of the received SDP offer matches the IP realm on the outgoing side (“the next IP realm associated with the connection information in the forwarded SDP offer”) of the ALG. Ex. 1103 at ¶¶ 0070-71. In other words, the ALG determines whether any preceding BG can connect to the next IP realm in the path. If there is no match, the ALG will not bypass any BGs. Id. at ¶¶ 0070-71, 0078-80. The ALG modifies the SDP offer by adding a new traversed-realm instance including IP realm information corresponding to a preceding BG’s connection and port information that was included in the media line in the
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incoming SDP offer. Id. at ¶ 0079. An IP realm “identif[ies] when one network entity is reachable from another via a fully interconnected common IP address space” and thus indicates connectivity. Id. at ¶ 0057; see also id. at ¶¶ 0042-44. Ex. 1104 at ¶¶ 84-89, 157. If there is a match, the ALG may replace “the connection and port information for the media line in the SDP offer with the connection and port information from the side of its BG directed toward the recipient of the forwarded SDP offer.” Ex. 1103 at ¶¶ 0077-78 and Ex. 1104 at ¶¶ 158-163.
Ejzak ’270 discloses Limitation [1e], “said preceding device connectivity data indicating at least one media connectivity setting for at least one preceding device . . . the at least one media connectivity setting identifying one or more other devices to which the preceding device is configured to be connectable in said media path.” Ex. 1104 at ¶¶ 143, 165-169. As discussed above, the ALG can modify an SDP offer to include IP realm information in the “traversed-realm” SDP extension field including a realm identifier, media connection information, port data, and other information about the previously traversed IP realms. Id. at ¶¶ 0055, 0122-131. The IP realm information of Ejzak ’270 therefore indicates a “media connectivity setting,” because it describes one or more parts, domains or regions of a telecommunications network to which a preceding BG (i.e., a BG in a previously traversed IP realms) has media connectivity. Id. and Ex. 1104 at ¶¶
166-169.
Ejzak ’270 discloses Limitation [1f], “...to enable bypass of said media gateway in said media path if an ensuing device in said outbound signaling path determines that such bypass should be conducted.” Ex. 1104 at ¶¶ 143, 170-179. If an ensuing ALG determines, based on preceding device IP realm information included in the traversed-realm extension of the forwarded SDP offer (see limitations [1c]-[1e] above), that the IP realm of a preceding device matches the IP realm on the outgoing side of the ensuing ALG, the ensuing ALG can bypass one or more border gateways (including the BG associated with the ALG that forwarded the SDP offer). Ex. 1103 at ¶¶ 0070-79; see also Ex. 1104 at ¶¶ 143, 170-179. This is disclosed in the example of “SDP Offer Case 3: Bypass Prior BGs,” in which, based on preceding IP realm information received in an SDP offer from a preceding ALG, ALG4 determines to bypass BG2 and BG3. Ex. 1103 at ¶¶ 0077-78 and Ex. 1104 at ¶¶ 143, 170-179.
The application of Ejzak ’270 to Claim 1 can also be understood in terms of Ejzak ’270’s “SDP Offer” Cases. Ex. 1103 at ¶¶ 0073-80; Ex. 1104 at ¶¶ 143, 158- 163, 174-176. Specifically, an ALG applying either SDP Offer Case 3 or 4 (in which the ALG does not bypass its controlled BG) performs all limitations of Claim 1, and enables an ensuing ALG applying either SDP Offer Case 1 or 3 (in which an ensuing ALG bypasses a prior BG) to bypass the ALG’s controlled BG.
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To the extent that Claim 1 is found to require that a single media gateway perform both signaling and media functions, it would have been obvious to one of ordinary skill in the art that the ALG and BG functions of Ejzak ’270 perform the same functions as the ’640 Patent media gateway and could be performed by a single device. See Ex. 1104 at ¶¶ 180-185. Ejzak ’270 teaches that each BG is controlled by its corresponding ALG and that the disclosed media bypass method may take place in a variety of hardware and/or software configurations. See Ex. 1103 at ¶¶ 0042, 0068, 0132-133. Furthermore, the ’640 Patent teaches that the media gateway recited in Claim 1 could be an SBC. See, e.g., Ex. 1101 at Claim 23 (“wherein the media gateway comprises a session border controller”). It was well-known in the prior art to combine the signaling and media functions into a single media gateway, such as an SBC. See Ex. 1104 at ¶ 184. Intel discloses an SBC having both media and signaling capabilities. Ex. 1111 at p. 2 (teaching a “session border controller . . . created to intercept and process calls on a VoIP network, allowing a single element to monitor not only the signaling traffic but also the media traffic,” and having media bypass capability). Thus, one of ordinary skill in the art would look to the well-known prior art techniques, such as those disclosed by Intel, to implement the method of Claim 1 of the ’640 Patent in a single media gateway such as a session border controller. Ex. 1104 at ¶¶ 183- 185.
Claims Ejzak ’270 and Intel [1a] A method of
enabling media bypass for a media gateway in a
telecommunications network which includes a plurality of media gateways via which a signaling path for transfer of signaling
information for setup of a communication session between endpoint devices can be established and via which a media path for transfer of media data between said endpoint
devices during said communication session can be established, said method comprising:
See, e.g., Ex. 1103 at Abstract, “A method for identifying alternate end-to-end media paths through internet protocol realms using substitute session description protocol
parameters is disclosed. The method includes receiving an session description protocol offer, including a list of
previously traversed through internet protocol realms. The method continues with determining the next internet protocol realm for a media path based on unspecified signaling criteria. Finally, the method includes that if the next internet protocol realm to be traversed through is on the list of previously traversed through internet protocol realms, bypassing at least one border gateway associated with the current and previously traversed through internet protocol realms.” (emphasis added)
See also Ex. 1103 at ¶ 0003, “A SIP based network call has a call signaling path and a bearer path. The call signaling path handles call control data which is used to set up, connect and process the call. The bearer path is the voice data connection over which a conversation takes place, and is also referred to as a multimedia session path or media path in this disclosure.”
See also Ex. 1103 at ¶ 0042, “FIG. 1 shows a typical call configuration between IP endpoints UA1 101 and UA2 131. SIP signaling goes between the UAs via at least one ALG and a variety of other SIP servers, which are not
33
Claims Ejzak ’270 and Intel
shown.”
See also Ex. 1103 at ¶ 0043, “An Application Layer Gateway (ALG) controls each border gateway to allocate new IP addresses and transport protocol ports as
necessary for each SDP media line and updates the SDP connection and port information in each forwarded SDP offer and SDP answer to effectively insert the border gateway into the end-to-end multimedia session path.” See also Ex. 1103 at ¶ 0068, “Generally, in this example, the method takes place in the ALG, however, it should be appreciated that this method may take place in a variety of hardware and/or software configurations.”
See also Ex. 1103 at Abstract; ¶¶ 0001; 0002; 0003-04; 0007; 0020; Fig. 1 and corresponding description; 0036; 0037; 0042-43; 0068-80.
See Ex. 1111 at 2, “Session border controllers were created to intercept and process calls on a VoIP network, allowing a single element to monitor not only the
signaling traffic but also the media traffic … the session border controller has the ability to intelligently route media – for example, directly between endpoints.” See also Ex. 1111 at Figure 1.
[1b] receiving, at said media gateway, an inbound
communication session setup request message requesting setup of a communication session between an originating endpoint device and a terminating endpoint device in said
See, e.g., Ex. 1103 at ¶ 0069, “When an ALG receives an SDP offer from a UA or another ALG (at step 201)…” (emphasis added)
See also Ex. 1103 at ¶ 0045, “RFC 3264 describes the SDP offer/answer model, which enables SIP networks to establish end-to-end media paths for multimedia
sessions. This disclosure describes an SDP extension attribute and some extensions to ALG procedures for forwarding SDP offers and SDP answers.” (emphasis added)
See also Ex. 1103 at Claim 1, “receiving a message including a list of previously traversed through internet
Claims Ejzak ’270 and Intel telecommunications
network, said inbound
communication session setup request message being
transmitted along an inbound signaling path to said media gateway;
protocol realms.” (emphasis added)
See also Ex. 1103 at Fig. 2 and corresponding description, including box 201:
See also Ex. 1103 at ¶ 0042, “FIG. 1 shows a typical call configuration between IP endpoints UA1 101 and UA2 131. SIP signaling goes between the UAs via at least one ALG and a variety of other SIP servers, which are not shown.”
See also Ex. 1103 at Abstract; Fig. 1; ¶¶ 0003; 0008; 0010; 0020; 0051; 0055; 0068-80; Claim 1.
[1c] transmitting, from said media gateway, an outbound
communication session setup request message in response to receiving said inbound communication session setup message, said outbound communication session setup request message being
transmitted along an outbound signaling path from said media
See, e.g., Ex. 1103 at ¶ 0079, “The ALG may also add a traversed-realm instance for the IP realm associated with the connection and port information for the media line in the forwarded SDP offer, and forward the modified SDP offer (at steps 219, 221).” (emphasis added)
See also Ex. 1103 at Fig. 2 and corresponding description, including box 221 (“Forward modified SDP offer”).
See also Ex. 1103 at ¶ 0042, “FIG. 1 shows a typical call configuration between IP endpoints UA1 101 and UA2 131. SIP signaling goes between the UAs via at least one ALG and a variety of other SIP servers, which are not shown.”
See also Ex. 1103 at Abstract; Fig. 1 and corresponding description; ¶¶ 0020; 0069-80.
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Claims Ejzak ’270 and Intel
gateway; and [1d] including preceding device connectivity data in said outbound communication session setup request message,
See, e.g., Ex. 1103 at ¶ 0079, “The ALG may also add a traversed-realm instance for the IP realm associated with the connection and port information for the media line in the forwarded SDP offer....” (emphasis added)
See also Ex. 1103 at ¶ 0055, “This disclosure defines an SDP extension attribute ‘traversed-realm’ that provides connection and port information for a prior IP realm traversed through on the signaling path. Each instance of traversed-realm has an instance number, realm identifier, connection and port data, and optional cryptographic signature computed using an algorithm private to each IP realm so as to ensure the integrity of the traversed-realm data.” (emphasis added)
See also Ex. 1103 at ¶ 0004, “In IMS and other SIP based networks, border gateways are deployed between IP realms defined by each network. Within an IP realm every IP endpoint is reachable from every other IP endpoint using a common IP address space.”
See also Ex. 1103 at ¶ 0057 (“An IP realm has two purposes: … 2) to identify when one network entity is reachable from another via a fully interconnected common IP address space.”); (emphasis added)
See also Ex. 1103 at Abstract; Figs. 1-2 (including boxes 215 and 217) and corresponding description; ¶¶ 0008; 0010; 0020-21; 0070-72; 0042-46; 0053-55; 0069-80; 0122-130; Claim 1.
[1e] said preceding device connectivity data indicating at least one media connectivity setting for at least one preceding device which is located
See, e.g., Ex. 1103 at ¶ 0055, “This disclosure defines an SDP extension attribute ‘traversed-realm’ that provides connection and port information for a prior IP realm traversed through on the signaling path. Each instance of traversed-realm has an instance number, realm
identifier, connection and port data, and optional cryptographic signature computed using an algorithm private to each IP realm so as to ensure the integrity of the
Claims Ejzak ’270 and Intel before said media
gateway in said inbound signaling path, the at least one media connectivity setting identifying one or more other devices to which the preceding device is configured to be connectable in said media path,
traversed-realm data.” (emphasis added)
See also Ex. 1103 at ¶ 0057 (“An IP realm has two purposes: … 2) to identify when one network entity is reachable from another via a fully interconnected common IP address space.”); (emphasis added)
See also Ex. 1103 at ¶ 0071, “The ALG then determines if a BG under its control has access both to the next IP realm associated with the connection information in the forwarded SDP offer and to an IP realm associated with a prior traversed-realm instance in the received SDP offer (at step 211).” (emphasis added)
See also Ex. 1103 at ¶ 0004, “In IMS and other SIP based networks, border gateways are deployed between IP realms defined by each network. Within an IP realm every IP endpoint is reachable from every other IP endpoint using a common IP address space.”
See also Ex. 1103 at Abstract; Fig. 1; ¶¶ 0020; 0042-44; 0070-72; 0073; 0075; 0077; 0079; 0122-131. [1f] to enable bypass of said media gateway in said media path if an ensuing device in said outbound signaling path
determines that such bypass should be conducted.
See, e.g., Ex. 1103 at Fig. 2 and corresponding description, including box 215:
See also Ex. 1103 at ¶ 0071, “The ALG then determines if a BG under its control has access both to the next IP realm associated with the connection information in the
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Claims Ejzak ’270 and Intel
forwarded SDP offer and to an IP realm associated with a prior traversed-realm instance in the received SDP offer (at step 211). In this case the ALG can bypass one or more BGs, including the one it controls. The ALG
should select the earliest IP realm accessible from the BG and determine the number of BGs that can be bypassed by substituting the connection and port information from this earliest IP realm into the forwarded SDP offer (at step 213).” (emphasis added)
See also Ex. 1103 at Abstract; Fig. 1 and corresponding description; ¶¶ 0020; 0070-79.
Thus, Ejzak ’270 in combination with Intel disclose each and every limitation of Claim 1. In particular, Ejzak ’270 discloses a method of media bypass in a telecommunications network including a plurality of media gateways (ALG for signaling / BG for media), in which a media gateway (ALG/BG) receives an inbound communication session setup request message (received SDP offer), transmits an outbound communication session setup request message (forwarded SDP offer), includes in the outbound message connectivity data (IP realm information in the traversed-realm extension) for a preceding device (a preceding ALG/BG), indicating a media connectivity setting (information about to which devices the preceding BG has connectivity) for the preceding device, which enables bypass of the media gateway in the media path if an ensuing device (a later ALG/BG) determines that such bypass should be conducted.