DETAILED ACTION
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 .
1. This communication is in response to amendments filed on 06/09/2026.
Claims 5, 6, 8-14, 19 and 20 have been amended.
Claims 1-20 remain pending.
Claim Objections
2. Applicant’s amendments to claims 5, 12 and 19 changing instances of “that” to “than” in response to the previously raised claim objection have been considered and obviate previous objection, as such the claim objection is hereby withdrawn.
Claim Rejections - 35 USC § 112
The following is a quotation of the first paragraph of 35 U.S.C. 112(a):
(a) IN GENERAL.—The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.
The following is a quotation of the first paragraph of pre-AIA 35 U.S.C. 112:
The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor of carrying out his invention.
Claims 6, 13 and 20 are rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, as failing to comply with the written description requirement. The claim(s) contains subject matter which was not described in the specification in such a way as to reasonably convey to one skilled in the relevant art that the inventor or a joint inventor, or for applications subject to pre-AIA 35 U.S.C. 112, the inventor(s), at the time the application was filed, had possession of the claimed invention. Specifically, for the following reason:
3. In response to the previously raised rejection under 35 U.S.C. 112(b) related to “each receiving spine device”, Applicant has amended claims 6, 13 and 20 to recite, “each receiving spine device receiving the network traffic until the network traffic reaches the at least one spine device, performing a corresponding downstream replication to different zones of the one or more zones than a zone assigned to the given leaf device”. This amendment is interpreted as intending that each spine device to which the network traffic is replicated upstream also performs downstream replication to different zones. This would include both the first spine device, the second spine device, and the at least one spine device disclosed in claims 3-6, 10-12 and 17-19.
It is submitted that the written specification and drawings, as originally filed, do not provide sufficient support for this feature. Specifically, the only paragraph of the specification corresponding to this limitation is [0029] which recites, “the upstream replication of the network traffic is repeated until the network traffic reaches at least one spine device with the corresponding depth having a highest value, with each receiving spine device performing a corresponding downstream replication to different zones of the one or more zones than a zone assigned to the given leaf device”. Each of FIG. 2 and FIGS. 5A-5D expressly illustrate that only SS1, which is the spine device having a depth with the highest level, performs downstream replication to different zones. Spine devices S1-S6 only perform downstream replication to leaf devices within the same zone, which is supported by claims 4, 11 and 18, from which claims 6, 13 and 20 respectively depend.
If Applicant believes that the specification does, in fact, provide support for every spine device which receives upstream network traffic also downstream replicating network traffic to different zones Applicant is urged to cite where this support can be found, or to amend the claim language to better reflect the features described in the written specification and drawings.
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.
Although Applicant’s amendments to claims 8-14 in response to the previously raised rejection under 35 U.S.C. 112(b) have been considered and obviate previous objection, claims 6, 13 and 20 remain rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention. Specifically for the following reason:
4. Claims 6, 13, and 20 were previously rejected for reciting, “the upstream replication” of the network traffic at the beginning of the claims because it was unclear which previous disclosure of upstream replication of network traffic disclosed in claims 3, 5, 10, 12, 17 and 20, from which claims 6, 13, and 20 respectively depend, “the upstream replication” in claims 6, 13, and 20 are intended to refer to. Applicant asserts that claim 3 recites that the upstream replication is to a first spine device, and that claim 5 further defines that the upstream replication is to a second spine device, with claim 6 further defining the upstream replication extending beyond the second spine device until the network traffic reaches a spine device having a highest depth, with the same analysis applying to claims 13 and 20.
In response, it is noted that claims 5, 12 and 19 recite “upstream replication of the network traffic” without any language that specifies these recitations refer to the same upstream replication of network traffic previously disclosed in claims 3, 10 and 17, from which claims 5, 12 and 19 respectively depend. In other words there are two distinct instances of upstream replication of the network traffic introduced in the claims from which 6, 13 and 20 depend. Applicant is urged to amend the recitation of “upstream replication of the network traffic” in claims 5, 12, and 19 to “the upstream replication of the network traffic” in order to clarify that each of these recitations is intended to refer to the same upstream replication of network traffic.
The rejection is therefore maintained.
Response to Arguments
5. Applicant's arguments asserting that the rejection under 35 U.S.C. 103 is improper because the combination of Ruan and Li references fail to teach or suggest “generating a corresponding replication list for each leaf device and one or more spine devices in the leaf-spine network fabric based at least in part of the corresponding depth and the one or more zones defined,” and “performing ingress replication of network traffic received at a given leaf device using the corresponding replication list of the given leaf device and the corresponding replication list of at least one of the one or more spine devices,” as recited in claim 1 with similar features recited in claims 8 and 15, have been fully considered but they are not persuasive.
In response, it is first noted that the Ruan reference is relied upon for teaching a leaf-spine network fabric with devices assigned depths and zones, and generating a network traffic forwarding policy based on these defined depths and zones. Applicant does not dispute this correlation, but submits that Ruan is directed to path selection and forwarding path information rather than replication list generation identifying recipient devices to which copies of traffic are replicated. Notably, the packet forwarding policies generated and provided to the leaf and spine devices in Ruan, like the replication lists of the claims, are generated based on defined device depths and zones within the fabric. It is the Li reference which is relied upon for teaching that a routing policy used for determining how traffic in a leaf-spine fabric is to be forwarded can include an ingress replication list. Both of the cited references, similarly to the claimed invention, are directed to leaf and spine devices applying routing policies and rules to optimize efficiently forwarding network traffic within the fabric.
In response to applicant's argument that the examiner's conclusion of obviousness is based upon improper hindsight reasoning, it must be recognized that any judgment on obviousness is in a sense necessarily a reconstruction based upon hindsight reasoning. But so long as it takes into account only knowledge which was within the level of ordinary skill at the time the claimed invention was made, and does not include knowledge gleaned only from the applicant's disclosure, such a reconstruction is proper. See In re McLaughlin, 443 F.2d 1392, 170 USPQ 209 (CCPA 1971). In this case, as evident by Li, use of replication lists for packet sending were known in the art before the effective filing date of the claimed invention, and it is submitted that it would have been obvious to utilize such replication lists in a spine and leaf fabric concerned with efficiently forwarding packets between spine and leaf devices in a network defined by tiers and zones. The claims lack any description regarding how depth and zone information is factored into the generation of the claimed replication list, or characteristics of the claimed replication list relating to how that information is applied in such a way that is specific to routing traffic between defined depths and zones. In other words, the claims do not describe the replication list in such a way which is distinct from replication lists used in other leaf-spine configurations, or include features of the replication list to support why substituting forwarding rules in Ruan with such a replication list would not be obvious.
It is therefore submitted that the claim language is broad enough that the teachings of the combination of Ruan and Li are within the scope of the argued claim limitations as currently recited, and the rejection is therefore maintained.
Claim Rejections - 35 USC § 103
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 (i.e., changing from AIA to pre-AIA ) 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.
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.
The factual inquiries 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.
6. Claims 1-20 are rejected under 35 U.S.C. 103 as being unpatentable over Ruan et al. (US 2021/0320820) in view of Li (US 2020/0374155).
Regarding claim 1, Ruan teaches a method comprising:
defining a corresponding depth for each leaf device and each spine device in a leaf-spine network fabric having a hierarchical structure (tier three switches are called Top-of-Rack switches (TORs) or Leaf switches, tier two switches are called Spine switches, and tier 1 switches are called Super Spine switches, [0262]);
defining one or more zones in the leaf-spine network fabric (data center network is organized as a plurality of “plan-of-deployment” units also referred to herein as “PoDs.” Each PoD is a modular unit of physical infrastructure that houses a set of network, compute, storage, and application components that work together to deliver networking services, [0263]; see FIG. 23);
generating a routing policy for each leaf device and one or more spine devices in the leaf-spine network fabric (with respect to full routing tables for the data center, only core switches 22 may need to perform full lookup operations, [0084]; install one or more policies within the devices of switch fabric 210, where the policies specify packet forwarding rules based on deterministic forwarding labels or other packet forwarding information carried within the headers of the packets injected into switch fabric 210 by DPUs 200, [0278]) based at least in part of the corresponding depth and the one or more zones defined (the FCP Path Index value assigned a given FCP leg is generated based on a combination of the peak point for FCP leg and an “FCP color” assigned to the network interface of the DPU on the FCP leg, [0006]; The “WithinPoD” sub-pool represents FCP Path Index values for FCP legs where a spine switch is the peak point (e.g., Spine 1-1 for traffic between DPU A and DPU B. The “AcrossPoD” sub-pool represents FCP Path Index values for FCP legs where a super spine switch is the peak point (e.g., Super Spine 4 for traffic between DPU A and DPU F, [0275]); and
performing ingress replication of network traffic received at a given leaf device (ToR 202, 204 of FIG. 23) using the corresponding routing policy of the given leaf device and the corresponding routing policy of at least one of the one or more spine devices (Switching devices within switch fabric 210 apply the installed routing/switching policies to direct the FCP packets along the particular paths based on the deterministic forwarding labels carried within the FCP packets, [0278]).
However, Ruan does not explicitly disclose the routing policy for each leaf device and one or more spine devices is a replication list.
Li teaches generating a corresponding replication list for each leaf device and one or more spine devices in a leaf-spine network fabric (Table 2 shows ingress replication lists on three devices, [0085]; see Table 2 on page 9).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed to utilize ingress replication lists for leaf and spine devices in the system/method of Ruan as suggested by Li to efficiently replicate BUM packets throughout the fabric. One would be motivated to combine these teachings because maintaining a list with each destination only appearing once at each switch device prevents duplicate BUM traffic from being sent a plurality of times to the same device and helps to maximize bandwidth utilization.
Regarding claim 2, Ruan teaches the method of claim 1, wherein the leaf-spine network fabric is a CLOS network (the switch fabric itself may be implemented using multiple layers of interconnected switches as in a CLOS network, [0076]; a data center network in which a set of DPUs 200 are connected to a typical CLOS switch fabric 210 used in a large-scale data center in which the intermediate switching/routing devices are arranged in a multi-stage switching arrangement, [0262]).
Regarding claim 3, Ruan teaches the method of claim 1, wherein performing the ingress replication includes upstream replication of the network traffic to a first spine device having the corresponding depth that is one level higher than the corresponding depth of the given leaf device (forwards the FCP packet of the sending (upstream) FCP Leg of the same color. In addition, DPU 200A constructs the output header of the FCP packet to specify a destination address of the peak point for the given FCP path. Finally, DPU 200A outputs the FCP packet on the network interface having the FCP color of the selected FCP Path Index, [0288], see FIG. 29), the first spine device being one of the one or more spine devices (One example FCP Path is, for example, the end-to-end path from DPU A to DPU B made up of a first FCP leg from DPU A to Spine 1 assigned the FCP Path Index “Path Index 2”, [0274]; Switching devices switch fabric 210 forward the FCP packet toward the peak point switching device along the FCP leg according to the outer IP header using standard IP-based switching/routing mechanism, [0279]).
Regarding claim 4, Ruan teaches the method of claim 3, wherein the ingress replication includes downstream replication of the network traffic, by the first spine device, to one or more additional leaf devices that are in a same zone of the one or more zones as the given leaf device (a second FCP leg from Spine 1 to DPU B having the same FCP Path Index “Path Index 2.”, [0274]; The “WithinPoD” sub-pool represents FCP Path Index values for FCP legs where a spine switch is the peak point (e.g., Spine 1-1 for traffic between DPU A and DPU B, [0275]; forwarding paths used between spine switches and the destination DPUs within a PoD (i.e., the downstream FCP Leg from the peak point of the FCP path), [0290]).
Regarding claim 5, Ruan teaches the method of claim 3, wherein,
the ingress replication includes upstream replication of the network traffic, by the first spine device, to a second spine device having the corresponding depth that is one level higher than the corresponding depth of the first spine device (Switching devices switch fabric 210 forward the FCP packet toward the peak point switching device along the FCP leg according to the outer IP header using standard IP-based switching/routing mechanism, [0279]; DPU 200A constructs the FCP packet to include an outer IP header having a destination IP address for super spine switch 230 such that the FCP packet is tunneled to the peak point (super spine switch 230) for the selected FCP Path 232, [0293]; see FIG. 30), and
the second spine device performs downstream replication of the network traffic to at least one third spine device with the corresponding depth one level lower than the corresponding depth of the second spine device, each of the at least one third spine device being in a different one of the one or more zones than the given leaf device (each spine switch of the PoDs in the data center is connected to at least one spine switch in each of the other PoDs in the data center by one or more super spine switches, which provide a third switching stage of switch fabric 210 referred to as the “super spine.”, [0264]; The “AcrossPoD” sub-pool represents FCP Path Index values for FCP legs where a super spine switch is the peak point (e.g., Super Spine 4 for traffic between DPU A and DPU F, [0275]; When super spine switch 230 removes the outer header of the packet, the super spine switch will be forced to forward the packet toward spine switch “Spine 2-2” in order to reach the YELLOW network interface of DPU 220F via ToR 234, [0293]).
Regarding claim 6, Ruan teaches the method of claim 5, wherein the upstream replication of the network traffic is repeated until the network traffic reaches at least one spine device with the corresponding depth having a highest value (the techniques define the concept of a “peak point,” which is the middle point (highest-level switching device) between a pair of DPUs within the data center switch fabric, [0006]; deterministic forwarding labels are used within the header of the FCP packets to direct each FCP packet toward the correct peak point for an FCP Path selected for the FCP packet, [0008]; the techniques define the concept of a “peak point,” which is the middle point (highest-level switching device) between two DPUs within the data center switch fabric, which is typically symmetric in arrangement. Depending on the physical connectivity between two DPUs, the peak point between the pair of DPUs could be a TOR switch, a spine switch or a super spine switch, [0269]; outer IP header having a destination IP address for super spine switch 230 such that the FCP packet is tunneled to the peak point (super spine switch 230), [0293]), with each receiving spine device receiving the network traffic until the network traffic reaches the at least one spine device, performing a corresponding downstream replication to different zones of the one or more zones than a zone assigned to the given leaf device (When super spine switch 230 removes the outer header of the packet, the super spine switch will be forced to forward the packet toward spine switch “Spine 2-2” in order to reach the YELLOW network interface of DPU 220F via ToR 234, [0293]; see FIG. 30).
Regarding claim 7, Ruan does not explicitly disclose the method of claim 1, wherein the network traffic is Broadcast, Unknown Unicast, and Multicast (BUM) traffic.
Li teaches wherein network traffic is Broadcast, Unknown Unicast, and Multicast (BUM) traffic (the dual-homing port may be used to transmit a BUM packet including a broadcast packet, a multicast packet, and an unknown unicast packet, [0061]; the BUM packet including the broadcast packet, the multicast packet, and the unknown unicast packet may be replicated to the VXLAN tunnel in the broadcast domain, [0085]).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to recognize BUM traffic in a leaf and spine fabric in the system/method of Ruan as suggested by Li to provide additional communication functionalities. One would be motivated to combine these teachings because it would enable services such as broadcast discovery requests, allowing traffic to endpoints with addresses not yet learned, and supporting efficient delivery of data to multiple receivers.
Claims 8 and 15 recite limitations equivalent to those in claim 1, and are therefore rejected in view of the same rationale.
Claims 9 and 16 recite limitations equivalent to those in claim 2, and are therefore rejected in view of the same rationale.
Claims 10 and 17 recite limitations equivalent to those in claim 3, and are therefore rejected in view of the same rationale.
Claims 11 and 18 recite limitations equivalent to those in claim 4, and are therefore rejected in view of the same rationale.
Claims 12 and 19 recite limitations equivalent to those in claim 5, and are therefore rejected in view of the same rationale.
Claims 13 and 20 recite limitations equivalent to those in claim 6, and are therefore rejected in view of the same rationale.
Claim 14 recites limitations equivalent to those in claim 7, and is therefore rejected in view of the same rationale.
Conclusion
THIS ACTION IS MADE FINAL. Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to MADHU WOOLCOCK whose telephone number is (571)270-3629. The examiner can normally be reached Tuesday, Thursday 9-6 ET.
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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.
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MADHU WOOLCOCK
Examiner
Art Unit 2451
/MADHU WOOLCOCK/Primary Examiner, Art Unit 2451
Prosecution Insights