DETAILED ACTION
Claims 1-30 are examined and pending.
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
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, 3, 8, 16, 18 and 23 are rejected under 35 U.S.C. 103 as being unpatentable over Duncan et al. (U.S. 2018/0324090 A1, hereinafter “Duncan”) in view of Li et al. (SPRING Working Group Internet-Draft, Compressed SRv6 Network programming, dated 08/28/2020)
As to claims 1 and 16, Duncan discloses A method implemented by an ingress network node in a segment routing (SR) multicast domain along a point-to-multipoint (P2MP) path, comprising:
receiving a packet from a traffic source (para. [0008]; discloses receiving a multicast flow );
encapsulating the packet with a segment routing header (SRH) that includes a sub-tree of the P2MP path through the SR multicast domain (para. [0004]; discloses segment routing being performed by applying a routing extension header. Para [0008], [0065]; discloses source nodes are used to construct source routed trees that define broadcast paths that illustrate P2MP tree for a multicast label in segment routing domain that are similar to the “P2MP path recited in limitation. The multicast flow is also assigned a segment identifier (SID) ),
sending the packet toward a next hop network node based on the SID of the SRH (para. [0086]; discloses traffic is transmitted toward a node using LSP based on SID and representing the link towards the next hop on each node).
However Duncan does not explicitly disclose the method wherein packet includes a reduced multicast segment identifier (rSID) for a link.
In an analogous art, Li discloses the method wherein the packet includes a reduced multicast segment identifier (rSID) for a link (page 3, 3. Compressed SID (C-SID); discloses including a C-SID in the compressed SRH header of the packet);
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify IPv6 packet in Duncan by incorporating a Compressed SID in the packet to be transmitted in the network as taught by Li in order to help reduce the overhead of the SRH to prevent the packet from being dropped due to its size (see Li, page 3, paragraph 2)
As to claim 3, Duncan-Li discloses the method of claim 1, further comprising setting a destination address (DA) of the packet to include: a multicast segment identifier (SID) locator of the next hop network node along the sub-tree and the rSID for the link along the sub-tree (page 4, 4. Compressed Segment routing header; discloses IPv6 DA with C-SID), wherein the rSID includes a link number (Link- No) of the link along the sub-tree (Page 4, Figure 2, “Locator”), a number of branches (N-Branches) of the next hop network node along the sub-tree, and a size of rSIDs (S-rSIDs) for rSIDs starting from an rSID for a first link from the next hop network node along the sub-tree (Pages 4 and 5, Figure 2 and Figure 3).
As to claim 8, Duncan-Li discloses the method of claim 1, wherein the SRH includes a segment left (SL) set to a number of normal segments used for a size of rSIDs (S-rSIDs) field in the rSID for the link along the sub-tree and rSIDs for links for sub-trees from the next hop network node along the P2MP path, and wherein each of the normal segments comprises 16 bytes (Li, page 5-6, Figure 3; discloses SRH includes segment list size of 16 bytes for the C-tag indicates the length of the C-SID ) .
As to claim 18, Duncan-Li discloses the ingress network node of claim 16, wherein the processor is further configured to set a destination address (DA) of the packet to include: a multicast segment identifier (SID) locator of the next hop network node along the sub-tree, and the rSID for the link along the sub-tree (Li, page 4, 4. Compressed Segment routing header; discloses IPv6 DA with C-SID), wherein the rSID includes a link number (Link-No) of the link along the sub-tree (Li, Page 4, Figure 2, “Locator”), a number of branches (N-Branches) of the next hop network node along the sub-tree, and a size of rSIDs (S-rSIDs) for rSIDs starting from an rSID for a first link from the next hop network node along the sub-tree (Li, Pages 4 and 5, Figure 2 and Figure 3).
As to claim 23, Duncan-Li discloses the ingress network node of claim 16, wherein the SRH includes a segment left (SL) set to a number of normal segments used for a size of rSIDs (S-rSIDs) in the rSID for the link along the sub-tree and rSIDs for links for sub-trees from the next hop network node along the P2MP path, and wherein each of the normal segments comprises 16 bytes (Li, page 5-6, Figure 3; discloses SRH includes segment list size of 16 bytes for the C-tag indicates the length of the C-SID ) .
Allowable Subject Matter
Claims 9-15, 24-30 are allowed.
The following is an examiner’s statement of reasons for allowance:
None of the prior art of record discloses, alone or in combination, the method wherein receiving a packet with a segment routing header (SRH) and a destination address (DA), wherein the SRH includes sub-trees from the transit network node, and wherein the DA includes a multicast segment identifier (SID) locator of the transit network node, a number of branches (N-Branches) field with a value indicating a number of the sub-trees from the transit network node, and a size of a reduced multicast segment identifiers (S-rSIDs) field with a value indicating a start of the sub-trees; duplicating the packet to generate a copy of the packet for each of the sub-trees, wherein a sub-tree of the sub-trees includes a reduced multicast segment identifier (rSID) for a link along the sub-tree; and sending the copy of the packet toward a next hop network node based on the rSID.
Any comments considered necessary by applicant must be submitted no later than the payment of the issue fee and, to avoid processing delays, should preferably accompany the issue fee. Such submissions should be clearly labeled “Comments on Statement of Reasons for Allowance.”
Claims 2, 4-7,17, 19-22, 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
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Previdi et al. (U.S. 2015/0256456 A1) discloses a system and method are disclosed for using segment routing (SR) in native IP networks. The method involves receiving a packet. The packet is an IP packet and includes an IP header. The method also involves updating the packet. Updating the packet involves writing information, including a segment routing segment identifier, to the destination address of the packet.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to JOE CHACKO whose telephone number is (571)270-3318. The examiner can normally be reached Monday-Friday 7am-5pm.
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, Ario Etienne can be reached at 5712724001. 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.
/JOE CHACKO/Primary Examiner, Art Unit 2457