DETAILED ACTION
Response to Amendment
Claims 1-15 are pending.
Response to Arguments
The pre-Appeal Brief dated 12/08/2025 and the Applicant’s Arguments dated 09/25/2025 have been fully considered.
Regarding the rejection of claim 1 under 35 U.S.C. 103 as being unpatentable over Wijnands et al. (Multicast Using Bit Index Explicit Replication (BIER). IETF RFC 8279. November 2017) in view of Pfister et al. (US20200228360A1), Applicant argues on page 1 of the pre-Appeal Brief that independent claim 1 is not rendered obvious by Wijnands and Wijnands/Pfister at least because these references neither teach, nor make obvious: A Bit Index Explicit Replication (BIER) sub-domain comprising: at least two BIER forwarding routers (BFRs) configured with a shared, non-zero, BIER forwarding router (BFR) identifier (BFR-ID) associated with a shared BFR-prefix, wherein the shared BFR-prefix of the at least two BFRs is an anycast address, whereby a packet transmitted to the any cast address is delivered to any one of the at least two BFRs, and wherein at least one of the at least two BFRs belongs to a single BFR subdomain.
Applicant’s arguments are not persuasive. In particular, Wijnands discloses “at least one of the at least two BFRs belongs to a single BFR subdomain” by showing [page 4 lines 27-33] for each sub-domain to which a given BFR belongs, it MUST be provisioned with a "BFR-id" that is unique within the sub-domain. If a given BFR belongs to more than one sub-domain, it may (though it need not) have a different BFR-id for each sub-domain (e.g., the given BFR may belong to a single sub-domain). Please refer to the complete rejection of claim 1 as discussed below.
Regarding claim 2, Applicant argues on page 3 that Wijnands and Wijnands/Pfister neither teach, nor make obvious claim 2.
In view of the amendment dated 08/25/2025 and after further consideration, claims 2-5 are rejected under 35 U.S.C. 112 as being incomplete for omitting essential steps, such omission amounting to a gap because it is not clear how processing determines to “not treating the first BFR-ID … as a duplicate and not log an error or ignore the duplicate” but “without any intervening check” as discussed in the 112 rejection below.
As to any argument not specifically addressed, they are the same as those discussed above.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 2-5 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being incomplete for omitting essential steps, such omission amounting to a gap between the processing steps. See MPEP § 2172.01.
Claims 2-5 recite “processing the at least one advertisement by not treating the first BFR-ID for the BIER sub-domain, associated with the first BFR-prefix as a duplicate and does not log an error or ignore the duplicate shared BFR-ID even though it is shared by a least two different BFRs in the BIER sub-domain, without any intervening check of whether or not the at least one advertisement includes an anycast indicator.” Applicant argues on page 11 of the Response filed 08/25/2025 that the limitation “without any intervening check” in claims 2-5 is supported in Fig 6 of instant Application showing the acts in block 650 follow those in block 640 without an intervening condition or check.
However, there is an omission amounting to a gap because “without any intervening check” it is not clear how the processing determines to “not treating the first BFR-ID …as a duplicate and not log an error or ignore the duplicate.” Therefore, claims 2-5 are rejected under 35 U.S.C. 112 as being incomplete for omitting essential steps.
Furthermore, block 650 in Fig. 6 of the instant Application discloses PROCESS, BY THE BFR, THE AT LEAST ONE ADVERTISEMENT IN A MANNER THAT DOES NOT TREAT THE COMMON BFR-ID ASSOCIATED WITH A COMMON BFR-PREFIX AS A DUPLICATE EVEN THOUGH IT IS SHARED BY A LEAST TWO DIFFERENT BFRS. The “IN A MANNER” is indefinite because it does not describe the essential step that must be executed for the process to NOT TREAT THE COMMON BFR-ID ASSOCIATED WITH A COMMON BFR-PREFIX AS A DUPLICATE EVEN THOUGH IT IS SHARED BY A LEAST TWO DIFFERENT BFRS.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 6-10 recite the limitation "another BFR”. There is insufficient antecedent basis for this limitation in the claim.
Claims 6-10 recite:
b) transmitting, by the first BFR, the at least one first advertisement to another BFR …
d) transmitting, by the second BFR, the at least one second advertisement to another BFR
It is not clear whether the “another BFR” in b) and d) are the same BFR or not.
It is not clear whether the “another BFR” in b) is the same as the “second BFR” in d) or not.
It is not clear whether the “another BFR” in d) is the same as the “first BFR” in b) or not.
It is not clear whether the “another BFR” in dependent claims 8-10 refer to which “another BFR” in independent claim 6.
Claims 11-15 recite the limitation "another BFR”. There is insufficient antecedent basis for this limitation in the claim.
Claims 11-15 recite:
a) 2) transmitting, by the first BFR, the at least one first advertisement to another BFR …
b) 2) transmitting, by the second BFR, the at least one second advertisement to another BFR
It is not clear whether the “another BFR” in a) 2) and b) 2) are the same BFR or not.
It is not clear whether the “another BFR” in a) 2) is the same as the “second BFR” in b) 2) or not.
It is not clear whether the “another BFR” in b) 2) is the same as the “first BFR” in a) 2) or not.
It is not clear whether the “another BFR” in dependent claims 13-15 refer to which “another BFR” in independent claim 11.
Claim Rejections - 35 USC § 103
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, 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.
Claims 1 and 6-15 are rejected under 35 U.S.C. 103 as being unpatentable over Wijnands et al. (Multicast Using Bit Index Explicit Replication (BIER). IETF RFC 8279. November 2017) in view of Pfister et al. (US20200228360A1).
Regarding claim 1, Wijnands discloses a Bit Index Explicit Replication (BIER) sub-domain comprising ([page 4 line 22] shows a BIER domain may contain one or more sub-domains):
at least two BIER forwarding routers (BFRs) configured with a shared, non-zero, BIER forwarding router (BFR) identifier (BFR-ID) associated with a shared BFR-prefix ([page 4 lines 9-10] shows a router that supports BIER is known as a "Bit-Forwarding Router" (BFR); [page 7 line 10] shows each BFR MUST be assigned a single "BFR-prefix" for each sub-domain to which it belongs; [page 12 lines 17-22] shows protocols and procedures that a given BFR uses to advertise to all other BFRs in the same BIER domain: its BFR-prefix; its BFR-id in each sub-domain for which it has been provisioned with a BFR-id; [page 4 lines 29-30] shows a BFR-id is a small unstructured positive integer, e.g., non-zero; [page 6 line 9] shows BFR-A has two BFR neighbors, BFR-B and BFR-C; [page 14 lines 14-22] shows these advertisements enable each BFR to associate a given <sub-domain-id, BFR-id> with a given BFR-prefix. If BFR-A determines that BFR-B and BFR-C have both advertised the same, e.g., shared, BFR-id for the same sub-domain, BFR-A MUST log an error. Suppose that the duplicate BFR-id is "N"), and
wherein at least one of the at least two BFRs belongs to a single BFR subdomain (page 4 lines 27-33] shows for each sub-domain to which a given BFR belongs, it MUST be provisioned with a "BFR-id" that is unique within the sub-domain. If a given BFR belongs to more than one sub-domain, it may (though it need not) have a different BFR-id for each sub-domain (e.g., a given BFR MUST be provisioned with a "BFR-id" that is unique within the sub-domain if it belongs to a single sub-domain.))
Wijnands discloses two different BFRs will not advertise ownership of the same <sub-domain-id, BFR-id> unless there has been a provisioning error ([page 14, lines 18-20]) but fails to teach the special case of an anycast address. In particular, Wijnands fails to show:
the shared BFR-prefix of the at least two BFRs is an anycast address,
whereby a packet transmitted to the anycast address is delivered to any one of the at least two BFRs.
However, Pfister discloses:
the shared BFR-prefix of the at least two BFRs is an anycast address (para [0038] shows each BIER-enabled node is assigned a unique identifier referred to as a “BFR-Prefix”; para [0094] shows the anycast bit positions are advertised as such, so that BIER-enabled nodes can incorporate this characteristic into their bit indexed routing and forwarding tables. Assignment of a standard BIER (anycast) bit position to more than one router is recognized as an exception to the treatment of conflicting bit positions),
whereby a packet transmitted to the anycast address is delivered to any one of the at least two BFRs (para [0094] shows in the case of an anycast bit position, a BIER enabled forwarding node forwards a message toward only one of multiple nodes sharing an anycast bit position.)
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to modify the method of Wijnands regarding two different BFRs will not advertise ownership of the same <sub-domain-id, BFR-id> unless there has been a provisioning error ([page 14, lines 18-19]) with the teaching of Pfister regarding the special case of an anycast address wherein the assignment of a standard BIER (anycast) bit position to more than one router is recognized as an exception to the treatment of conflicting bit positions (para [0094]) in order to treat anycast as an exception to the treatment of conflicting bit positions (Pfister; para [0094]).
Regarding claim 6, Wijnands discloses a computer-implemented method for use in a Bit Index Explicit Replication (BIER) sub-domain, the computer-implemented method comprising ([page 4 lines 9-10] shows a router that supports BIER is known as a "Bit-Forwarding Router" (BFR); [page 5 line 10] shows each BFR MUST be assigned a single "BFR-prefix" for each sub-domain to which it belongs):
generating, by a first BFR in the BIER subdomain, at least one first advertisement collectively having a non-zero BIER forwarding router (BFR) identifier (BFR-ID) for the BIER sub-domain, associated with a BFR-prefix belonging to the BIER sub-domain; b) transmitting, by the first BFR, the at least one first advertisement to another BFR in the BIER sub-domain ([page 12 lines 17-22] shows protocols and procedures that a given BFR uses to advertise to all other BFRs in the same BIER domain: its BFR-prefix; [page 4 lines 29-30] shows a BFR-id is a small unstructured positive integer, e.g., non-zero; [page 14 lines 14-22] shows these advertisements enable each BFR to associate a given <sub-domain-id, BFR-id> with a given BFR-prefix);
generating, by a second BFR in the BIER subdomain, at least one second advertisement collectively having the non-zero BIER forwarding router (BFR) identifier (BFR-ID) for the BIER sub-domain, associated with the BRF-prefix belonging to the BIER sub-domain; and d) transmitting, by the second BFR, the at least one second advertisement to another BFR in the BIER sub-domain ([page 6 line 9] shows BFR-A has two BFR neighbors, BFR-B and BFR-C; [page 14 lines 21-22] shows if BFR-A determines that BFR-B and BFR-C have both advertised the same BFR-id for the same sub-domain, BFR-A MUST log an error), and
wherein at least one of the first BFR and the second BFR belongs to a single BFR subdomain ([page 4 lines 27-33] for each sub-domain to which a given BFR belongs, it MUST be provisioned with a "BFR-id" that is unique within the sub-domain. If a given BFR belongs to more than one sub-domain, it may (though it need not) have a different BFR-id for each sub-domain (e.g., a given BFR MUST be provisioned with a "BFR-id" that is unique within the sub-domain if it belongs to a single sub-domain.))
Wijnands discloses two different BFRs will not advertise ownership of the same <sub-domain-id, BFR-id> unless there has been a provisioning error ([page 14, lines 18-19]) but fails to teach the special case of an anycast address. In particular, Wijnands fails to show:
the BFR-prefix of the at least two BFRs is an anycast address, whereby a packet transmitted to the anycast address is delivered to any one of the first and second BFRs.
However, Pfister discloses:
the BFR-prefix of the at least two BFRs is an anycast address, whereby a packet transmitted to the anycast address is delivered to any one of the first and second BFRs (para [0038] shows each BIER-enabled node is assigned a unique identifier referred to as a “BFR-Prefix”; para [0094] shows the anycast bit positions are advertised as such, so that BIER-enabled nodes can incorporate this characteristic into their bit indexed routing and forwarding tables. Assignment of a standard BIER bit position to more than one router is recognized as an exception to the treatment of conflicting bit positions; in the case of an anycast bit position, a BIER enabled forwarding node forwards a message toward only one of multiple nodes sharing an anycast bit position).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to modify the method of Wijnands regarding two different BFRs will not advertise ownership of the same <sub-domain-id, BFR-id> unless there has been a provisioning error ([page 14, lines 18-19]) with the teaching of Pfister regarding the special case of an anycast address wherein the assignment of a standard BIER (anycast) bit position to more than one router is recognized as an exception to the treatment of conflicting bit positions (para [0094]) in order to treat anycast as an exception to the treatment of conflicting bit positions (Pfister; para [0094]).
Regarding claim 7, Wijnands-Pfister as applied to claim 6 discloses each of the first BFR and the second BFR is an egress BFR (BFER) (Wijnands; [page 1 lines 21-22] shows when a multicast data packet enters the domain, the ingress router determines the set of egress routers to which the packet needs to be sent; [page 6 line 9] shows BFR-A has two BFR neighbors, BFR-B and BFR-C.)
Regarding claim 8, Wijnands-Pfister as applied to claim 6 discloses the acts of (1) generating, by a first BFR in the BIER subdomain, at least one first advertisement collectively having a non-zero BIER forwarding router (BFR) identifier (BFR-ID) for the BIER sub-domain, associated with a BFR-prefix belonging to the BIER sub-domain, and (2) transmitting, by the first BFR, the at least one first advertisement to another BFR in the BIER sub-domain, are performed regardless of whether or not the first BFR had previously received an advertisement from another BFR in the BFR sub-domain having the non-zero BFR-ID for the BIER sub-domain, associated with the BFR-prefix (Pfister; para [0038] shows each BIER-enabled node is assigned a unique identifier referred to as a “BFR-Prefix”; para [0094] shows the anycast bit positions are advertised as such, so that BIER-enabled nodes can incorporate this characteristic into their bit indexed routing and forwarding tables. Assignment of a standard BIER (anycast) bit position to more than one router is recognized as an exception to the treatment of conflicting bit positions. In the case of an anycast bit position, a BIER enabled forwarding node forwards a message toward only one of multiple nodes sharing an anycast bit position.)
Regarding claim 9, Wijnands-Pfister as applied to claim 6 discloses the act of transmitting, by the first BFR, the at least one first advertisement to another BFR in the BIER sub-domain, uses flooding (Pfister; para [0038] shows each BIER-enabled node advertises or floods the routable address to all other BIER-enabled nodes in network 100.)
Regarding claim 10, Wijnands-Pfister as applied to claim 6 discloses the act of transmitting, by the first BFR, the at least one first advertisement to another BFR in the BIER sub-domain, uses an interior gateway protocol (IGP) (Wijnands; [page 11 lines 18-19] shows Interior Gateway Protocol (IGP).)
Regarding claims 11-15, claims 11-15 are directed to a BIER subdomain. Claims 11-15 require limitations that are similar to those recited in the claims 6-10 to carry out the method steps. And since Wijnands-Pfister combined discloses the method including limitations required to carry out the method steps, therefore claims 11-15 would have also been unpatentable over Wijnands-Pfister combined.
Conclusion
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/TAN DOAN/Primary Examiner, Art Unit 2445