CTNF 19/056,349 CTNF 85251 DETAILED ACTION This action is in response to communication filed on 9/11/2025. Claims 21-40 are pending. Claims 1-20 have been cancelled. Notice of Pre-AIA or AIA Status 07-03-aia AIA 15-10-aia The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA. Information Disclosure Statement The information disclosure statement (IDS) submitted on 3/26/2025 and 10/31/2025 is in compliance with the provisions of 37 CFR 1.97. Accordingly, the information disclosure statement is being considered by the examiner. Claim Rejections - 35 USC § 103 07-06 AIA 15-10-15 In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status. 07-20-aia AIA The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action: A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102 of this title, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made. 07-23-aia AIA The factual inquiries set forth in Graham v. John Deere Co. , 383 U.S. 1, 148 USPQ 459 (1966), that are applied for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows: 1. Determining the scope and contents of the prior art. 2. Ascertaining the differences between the prior art and the claims at issue. 3. Resolving the level of ordinary skill in the pertinent art. 4. Considering objective evidence present in the application indicating obviousness or nonobviousness. 07-21-aia AIA Claim s 21-22, 24-25, 27, 31-32, 34-35, 37, 39-40 are rejected under 35 U.S.C. 103 as being unpatentable over Brissette et al. (US 2018/0375763) in view of Sajassi et al. (RFC 7432) . Regarding claim 21 , Brissette discloses a method, comprising: generating, by a first communication apparatus, a first border gateway protocol (BGP) message used for advertising a first Ethernet virtual private network media access control (EVPN MAC) route (Brissette discloses a communication apparatus (PE/BGP speaker) generating a BGP message (MP-BGP Update containing EVPN NLRI) whose purpose is advertising an EVPN MAC route; [0065-0077] “ EVPN route type-2 is used to advertise MAC or MAC+IP address reachability for unicast traffic through MP-BGP to all other PEs in a given EVPN instance. In one embodiment, a MAC/IP Advertisement route type is encoded as follows for SRv6 Core:...”) . However, the prior art does not explicitly disclose the following: wherein the first BGP message comprises a first media access control (MAC) address and first indication information, and the first indication information indicates a priority of the first EVPN MAC route; and sending, by the first communication apparatus, the first BGP message to a second communication apparatus. Sajassi in the field of the same endeavor discloses defines a scalable BGP based control plane for Ethernet PVNs over MPLS networks, in which Provider Edge routers use MP-BGP to advertise specialized EVPN routes types (including MAC/IP advertisement routes) together with extended communities to distribute MAC reachability, support multi-homing, and handle MAC mobility. In particular, Sajassi teaches the following: wherein the first BGP message comprises a first media access control (MAC) address and first indication information (Sajassi discloses that the same BGP message that carries the MAC/IP advertisement route (which includes the MAC address in the NLRI) also carries indication information in the form of extended communities attributes such as the default gateway extended community and the MAC mobility extended community; section 7.2, “ A MAC/IP Advertisement route type specific EVPN NLRI consists of the following: … PNG media_image1.png 75 392 media_image1.png Greyscale … For the purpose of BGP route key processing, only the Ethernet Tag ID, MAC Address Length, MAC Address, IP Address Length, and IP Address fields are considered to be part of the prefix in the NLRI ”), and the first indication information indicates a priority of the first EVPN MAC route (Sajassi; section 7.7 (MAC Mobility Extended Community) and section 7.8 and 10.1 (Default Gateway Extended Community). These extended communities are defined to be advertised along with MAP/IP advertisement routes and serve as indication information that signals special status or control routes selection/priority) ; and sending, by the first communication apparatus, the first BGP message to a second communication apparatus (Sajassi, section 10.1; “ Each PE that acts as a default gateway for a given EVPN instance MAY advertise in the EVPN control plane its default gateway MAC address using the MAC/IP Advertisement route, and each such PE indicates that such a route is associated with the default gateway. This is accomplished by requiring the route to carry the Default Gateway extended community defined in Section 7.8 ("Default Gateway Extended Community "”) . Therefore, it would have been obvious to a person of ordinary skill in the art at the time the invention was effectively filed to combine the prior art with the teaching of Sajassi. One would have been motivated because Brissette explicitly builds upon and extends the core EVPN route advertisement mechanisms, MAC/IP advertisement routes, and extended community signaling defined in Sajassi by adding SRv6 underlay support, as shown by Brissett’s repeated citations to Sajassi for the base EVPN structures and procedures. Regarding claim 22 , Brissette-Sajassi discloses the method according to claim 21, wherein the first communication apparatus is a gateway (Sajassi, section 10.1, “ the PE that performs such a function is called the default gateway for the EVPN instance ”) . Regarding claim 24 , Brissette-Sajassi discloses the method according to claim 21, wherein an extended communities attribute of the first BGP message comprises the first indication information (Sajassi section 7.8 “ The Default Gateway community is an Extended Community of an Opaque Type (see Section 3.3 of [RFC4360]). It is a transitive community, which means that the first octet is 0x03. The value of the second octet (Sub-Type) is 0x0d (Default Gateway) as assigned by IANA. The Value field of this community is reserved (set to 0 by the senders, ignored by the receivers )”) . Regarding claim 25 , Brissette-Sajassi discloses the method according to claim 24, wherein the extended communities attribute is an extended communities attribute for MAC migration or an extended communities attribute of a default gateway (Sajassi section 7.7 “ This Extended Community is a new transitive Extended Community having a Type field value of 0x06 and the Sub-Type 0x00. It may be advertised along with MAC/IP Advertisement routes… The MAC Mobility extended community is encoded as an 8-octet value, as follows: PNG media_image2.png 121 638 media_image2.png Greyscale The sequence number is used to ensure that PEs retain the correct MAC/IP Advertisement route when multiple updates occur for the same MAC address ”) . Regarding claim 27 , Brissette-Sajassi discloses the method according to claim 21, wherein: the first indication information indicates that the first MAC address is of an access-side apparatus of a gateway, and the first indication information implicitly indicates the priority of the first EVPN MAC route by using the first indication information to indicate that the first MAC address is of the access-side apparatus of the gateway; or the first indication information comprises an identifier of the priority (Sajassi discloses the MAC mobility extended community contains a sequence number field. This sequence number is the “identified of the priority.” It is carried as part of the indication information in the extended communities attribute of the BGP message advertising the EVPN MAC route; section 7.7 “ This Extended Community is a new transitive Extended Community having a Type field value of 0x06 and the Sub-Type 0x00. It may be advertised along with MAC/IP Advertisement routes…the MAC Mobility extended community is encoded as an 8-octet value, as follows: PNG media_image3.png 129 640 media_image3.png Greyscale …The sequence number is used to ensure that PEs retain the correct MAC/IP Advertisement route when multiple updates occur for the same MAC address ”, section 15 “Every MAC mobility event for a given MAC address will contain a sequence number that is set using the following rules… A PE detecting a locally attached MAC address for which it had previously received a MAC/IP Advertisement route with a different Ethernet segment identifier advertises the MAC address in a MAC/IP Advertisement route tagged with a MAC Mobility extended community attribute with a sequence number one greater than the sequence number in the MAC Mobility extended community attribute of the received MAC/IP Advertisement route ”) , and the first indication information indicates the priority of the first EVPN MAC route by using the identifier of the priority. Regarding claim(s) 31-32, 34-35, 37 and 39-40 , do(es) not teach or further define over the limitation in claim(s) 21-22, 24-25, 27 and 21 and 24 respectively. Therefore claim(s) 31-32, 34-35, 37 and 39-40 , is/are rejected for the same rationale of rejection as set forth in claim(s) 21-22, 24-25, 27 and 21 and 24 respectively . 07-21-aia AIA Claim s 23-33 are rejected under 35 U.S.C. 103 as being unpatentable over Brissette et al. (US 2018/0375763) in view of Sajassi et al. (RFC 7432) in view of Thoria et al. (US 2022/0417141) . Regarding claim 23 , Brissette-Sajassi discloses the invention substantially, however the prior art does not explicitly disclose the method according to claim 21, wherein a role of the first communication apparatus is Sleaf, and a role of the second communication apparatus is Aleaf. Thoria in the field of the same endeavor discloses techniques for enabling interoperability between asymmetric and symmetric Integrated Routing and Bridging (IRB) modes. In particular, Thoria teaches the following: wherein a role of the first communication apparatus is Sleaf (Thoria [0042] “ In a symmetric IRB PE 500, an EVPN MAC and IP advertisement route is built and advertised to the other PE's participating in the EVPN. The MPLS Label2 field is set to either an MPLS label or a VNI corresponding to the tenant's IP-VRF. The inclusion of MPLS Label2 field signals to the receiving PE that the route is for symmetric IRB mode ”) , and a role of the second communication apparatus is Aleaf (Thoria [0043] “ If the receiving PE only supports asymmetric IRB mode, then the receiving PE must ignore the Label2 field and install the MAC address in the corresponding MAC-VRF and the IP and MAC address in the ARP table ”) . Therefore, it would have been obvious to a person of ordinary skill in the art at the time the invention was effectively filed to combine the prior art with the teaching of Thoria. One would have been motivated because Thoria teaches the known use of differentiated leaf roles (Sleaf?Aleaf or equivalent access vs. other leaf distinctions) in EVPN fabrics to enable role-specific BGP EVPN MAC route advertisement, priority signaling, and gateway/non-gateway interaction behaviors for improved scalability and targeted forwarding in hierarchical multi-tier data center networks. Regarding claim(s) 33 , do(es) not teach or further define over the limitation in claim(s) 23 respectively. Therefore claim(s) 33 is/are rejected for the same rationale of rejection as set forth in claim(s) 23 respectively . 07-21-aia AIA Claim s 26 and 36 are rejected under 35 U.S.C. 103 as being unpatentable over Brissette et al. (US 2018/0375763) in view of Sajassi et al. (RFC 7432) in view of Chandra et al. (RFC 1997) . Regarding claim 26 , Brissette-Sajassi discloses the invention substantially, however the prior art does not explicitly discloses the method according to claim 21, wherein a communities attribute of the first BGP message comprises the first indication information Chandra in the field of the same endeavor defines the optional transitive BGP communities path attribute (type code 8) that tags routes with 4 octet community values so BGP speakers can apply common policies for acceptance, preference, filtering, and distribution to groups of destinations sharing the same community. In particular, Chandra teaches the following: wherein a communities attribute of the first BGP message comprises the first indication information (Chandra discloses that the stand communities attribute is included in BGP update message and carries community values that represent properties of the route. These values can be used by receiving BGP speakers to control acceptance, preference (i.e., priority), or distribution of the route; pg. 2-3, section COMMUNITIES attribute “ This document creates the COMMUNITIES path attribute is an optional transitive attribute of variable length. The attribute consists of a set of four octet values, each of which specify a community. All routes with this attribute belong to the communities listed in the attribute. The COMMUNITIES attribute has Type Code 8 ”, pg. 3, section Operation “ A BGP speaker may use this attribute to control which routing information it accepts, prefers or distributes to other neighbors ”) . One of ordinary skill would recognize that a specific community value can serve as the “first indication information” that indicates the priority of an EVPN MAC router advertised in the same BGP message. Therefore, when combined with Brissette in view of Sajassi, It would have been obvious to place the priority indication inside the standard communities attribute rather than the extended communities or prefix SID attributes shown in the primary references. This is a substitution of one known BGP path attribute for another to carry analogous indication information for a known purpose, which is proper under MPEP 2143. Regarding claim(s) 36 , do(es) not teach or further define over the limitation in claim(s) 26 respectively. Therefore claim(s) 36 is/are rejected for the same rationale of rejection as set forth in claim(s) 26 respectively . 07-21-aia AIA Claim 28 is rejected under 35 U.S.C. 103 as being unpatentable over Brissette et al. (US 2018/0375763) in view of Rabadan et al. (RFC 9014) . Regarding claim 28 , Brissette-Sajassi discloses the invention substantially, however the prior art does not explicitly disclose the method according to claim 21, further comprising: receiving, by the first communication apparatus, a second EVPN MAC route advertised by the second communication apparatus, wherein the second EVPN MAC route is an unknown media access control route (UMR) with an all-zero MAC address. Rabadan in the field of the same endeavor discloses techniques for Network Virtualization Overlays (NVOs) connecting to a Wide Area Network (WAN) in order to extend the Layer 2 connectivity required for some tenants. In particular, Rabadan teaches the following: receiving, by the first communication apparatus, a second EVPN MAC route advertised by the second communication apparatus (Rabadan discloses GW advertising the route into the DC, and an NVE receiving and processing the advertised route; section 3.5.1 “ The solution specified in this document uses the Unknown MAC Route (UMR) that is advertised into a given DC by each of the DC's GWs… An NVE within that DC that understands and processes the UMR will send unknown unicast frames to one of the DC's GWs, which will then forward that packet to the correct egress PE ”) , wherein the second EVPN MAC route is an unknown media access control route (UMR) with an all-zero MAC address (Rabadan; section 3.5.1 “ This route is defined in [RFC7543] and is a regular EVPN MAC/IP Advertisement route in which the MAC Address Length is set to 48, the MAC address is set to 0, and the ESI field is set to the DC GW's I-ESI ”) . Therefore, it would have been obvious to a person of ordinary skill in the art at the time the invention was effectively filed to combine the prior art with the teaching of Rabadan. One would have been motivated to improve unknown unicast unhanding and reduce MAC scale on leaves/NVEs by advertising a single catch all UMR from gateways, as described in Rabadan . Allowable Subject Matter 12-151-08 AIA 07-43 12-51-08 Claim s 29-30 and 38 are objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims. Conclusion For the reason above, claims 21-40 have been rejected and remain pending. Any inquiry concerning this communication or earlier communications from the examiner should be directed to JIMMY H TRAN whose telephone number is (571)270-5638. The examiner can normally be reached Monday-Friday 9am-5pm PST. Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice. If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Chris Parry can be reached at 571-272-8328. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300. Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000. JIMMY H TRAN Primary Examiner Art Unit 2451 /JIMMY H TRAN/Primary Examiner, Art Unit 2451 Application/Control Number: 19/056,349 Page 2 Art Unit: 2451 Application/Control Number: 19/056,349 Page 3 Art Unit: 2451 Application/Control Number: 19/056,349 Page 4 Art Unit: 2451 Application/Control Number: 19/056,349 Page 5 Art Unit: 2451 Application/Control Number: 19/056,349 Page 6 Art Unit: 2451 Application/Control Number: 19/056,349 Page 7 Art Unit: 2451 Application/Control Number: 19/056,349 Page 8 Art Unit: 2451 Application/Control Number: 19/056,349 Page 9 Art Unit: 2451 Application/Control Number: 19/056,349 Page 10 Art Unit: 2451
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