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 .
DETAILED ACTION
2. This action is in response to the Request for Continued Examination and Amendment filed July 16, 2026.
3. Claims 1, 2, 8, and 15 have been amended.
4. Claims 1-20 have been examined and are pending with this action.
Response to Arguments
5. Applicant's arguments filed July 16, 2026 with respect to the rejections of claims 1, 4, 6-8, 11, 13-15, 18, and 20, previously rejected under 35 U.S.C. 102(a)(1) and 102(a)(2) as being anticipated by Agarwal et al. (US 2023/0362210 A1), have been fully considered and are persuasive. However, upon further consideration and/or searching, Noldus (US 2012/0185613 A1), herein referenced Noldus, has been cited to better teach the newly amended limitation. Please see rejections below.
For at least these reasons above and the rejections set forth below, claims 1-20 have been rejected and remain pending.
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.
6. Claims 1-4, 6-11, 13-18, and 20 are rejected under 35 U.S.C. 103 as being unpatentable over Agarwal et al. (US 2023/0362210 A1) in view of Noldus (US 2012/0185613 A1).
INDEPENDENT:
As per claim 1, Agarwal teaches a method of performing proxy call session control function (P-CSCF) selection in a telecommunications network (see Agarwal, [0054]: "The message may be used for triggering an initiation of an address list update procedure with UE 102 and other UEs (step 432 of FIG. 4), for a reselection of a new P-CSCF for the service by UE 102 as well as the other UEs. The reselection may be performed with use of a procedure for session release with reactivation (step 434 of FIG. 4)"), the method comprising:
receiving a registration request at a first network node of the telecommunication network, the registration request including a request from a user equipment (UE) to establish an Internet Protocol (IP) Multimedia Subsystem (IMS) connection (see Agarwal, [0050]: "UE 102 may send a message for registration in the mobile network and establish a PDU session via a PDU establishment procedure (step 402 of FIG. 4). UE 102 has address information, stored in memory, associated with a P-CSCF for an IMS service. Using the address information, UE 102 may send to P-CSCF-1 192 a message for SIP registration (step 404 of FIG. 4)"); and
after resolving the health statuses, transmitting at least one P-CSCF IP address to the UE based on the resolved health statuses of the plurality of candidate P-CSCFs, thereby to cause the UE to establish the IMS connection (see Agarwal, [0005]: "To establish service, a user equipment (UE) may receive a P-CSCF address of the P-CSCF in a message which includes a Protocol Configuration Options (ePCO) container"; [0044]: "A P-CSCF is an IMS core component that performs IMS signaling processing for IMS services. To establish service, a UE may receive an address of the P-CSCF in a message which includes a Protocol Configuration Options (ePCO) container"; [0023]: "Based on the identifying, the UPF may send, to the SMF, a message for reporting the failure of the application or control function. The message may trigger, at the SMF, an initiation of an address list update procedure for a reselection of a new application or control function of the network for the voice or data service by the one or more UEs. The one or more UEs may be a plurality of UEs which are updated with new address information for the voice or data service. In some implementations, the ping procedure may involve sending a SIP OPTIONS message to query for operational status of the application or control function"; [0044]: “… updated address list and sent to UEs during IMS Packet Data Unit (PDU) session setups (e.g. for new calls or as part of IMS restoration procedures)-”; [0054]: “The message may be used for triggering an initiation of an address list update procedure with UE 102 and other UEs (step 432 of FIG. 4), for a reselection of a new P-CSCF for the service by UE 102 as well as the other UEs. The reselection may be performed with use of a procedure for session release with reactivation (step 434 of FIG. 4)”; and [0055]: “Section 5.8.3.2, to send a new P-CSCF address to all UEs that are using UPF 120 that reported the P-CSCF service failure. Although this is a failure detection for a single UE 102, the restoration action may be triggered for all UEs associated with that UPF 120 with the failed P-CSCF. This may therefore be considered to be a proactive IMS service recovery operation that is achieved for multiple UEs.”).
Although Agarwal further teaches resolving a health status for each P-CSCF of a plurality of candidate P-CSCFs (see Agarwal, [0023]: "The UPF may invoke a failure detection monitoring procedure for monitoring the application or control function associated with the address information of the application or control function… In some implementations, the ping procedure may involve sending a SIP OPTIONS message to query for operational status of the application or control function. "; [0028]: "Techniques and mechanisms for Fifth Generation (5G) System (5GS) monitoring and detection of failure of a Proxy-Call Session Control Function (P-CSCF) of an IP Multimedia System (IMS) for efficient restoration of IMS service for multiple mobile devices”; and [0029]: "… for (e.g. a more proactive) restoration of service for multiple mobile devices in response to P-CSCF failure. The ping procedure may involve a Session Initiation Protocol (SIP) OPTIONS ping or an Internet Control Message Protocol (ICMP) ping."; [0030]: “… using a subscription-notification or a request-response mechanism, for (e.g. a more proactive) restoration of service for multiple mobile devices in response to P-CSCF failure.”; and [0048]: “the ping procedure may involve sending a SIP OPTIONS message to query for operational status of the application or control function.”), Agarwal does not explicitly teach the resolution is in response to the registration request.
Noldus teaches resolution in response to a registration request (see Noldus, [0074]: “The actual registration process of the IMS subscriber (SIP-UA) is done through a selected one P-CSCF entity of the plurality of P-CSCF entities 4.i. In this example, the SIP-UA contacts a Domain Name Server (DNS) 16 for retrieving a network address corresponding to the selected P-CSCF entity. Thereto, the SIP-UA may use the retrieving means 18. Here DNS name resolving of the P-CSCF group identifier by the SIP-UA yields the network address, e.g. IP address, of one particular P-CSCF through which the registration shall be done. This particular P-CSCF is used for the registration process. It will be appreciated that the SIP-UA now has derived the network address of one P-CSCF entity of the plurality of P-CSCF entities on the basis of the P-CSCF group identifier. It will be appreciated that DNS may return multiple network addresses, e.g. multiple IP addresses, related to multiple P-CSCF entities of the plurality of P-CSCF entities 4.i. The SIP-UA 2 may in such case select one network address for the registration process using the selection means 26. It will be appreciated that the SIP-UA now has selected the network address of one P-CSCF entity of the plurality of P-CSCF entities on the basis of the P-CSCF group identifier”).
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the invention to modify the system of Agarwal in view of Srinivasan by implementing resolving a health status in response to a registration request. One would be motivated to do so because it is well-known, widely implemented, routine, and/or conventional to resolve the health status of each P-CSCF of the plurality of candidate P-CSCF in response to a registration request because the registration request requires the network to assign or use a P-CSCF that can actually handle the registration. If the network has a plurality of candidate P-CSCF as taught by Agarwal, their operational condition is directly relevant to choosing one.
As per claim 8, Agarwal and Noldus teach a telecommunications network comprising: at least one first processor in communication with a first network node of the telecommunications network (see Agarwal, [0047]: "The method may be embodied as a computer program product including a non-transitory computer readable medium (e.g. one or more memory elements) and instructions stored in the computer readable medium, where the instructions are executable on one or more processors for performing the steps of the method. In some implementations, the instructions stored in the one or more memory elements may be executable on the one or more processors for operation as a UPF."); and
a first memory storing first instructions that, when executed by the at least one first processor, cause the first network node (see Agarwal, [0047]: "The method may be embodied as a computer program product including a non-transitory computer readable medium (e.g. one or more memory elements) and instructions stored in the computer readable medium, where the instructions are executable on one or more processors for performing the steps of the method. In some implementations, the instructions stored in the one or more memory elements may be executable on the one or more processors for operation as a UPF.") to:
receive a registration request at a first network node of the telecommunication network, the registration request including a request from a user equipment (UE) to establish an Internet Protocol (IP) Multimedia Subsystem (IMS) connection (see Claim 1 rejection above),
in response to the registration request, resolve a health status for each P-CSCF of a plurality of candidate P-CSCFs (see Claim 1 rejection above), and
after resolving the health statuses, transmit at least one P-CSCF IP address to the UE based on the resolved health statuses of the plurality of candidate P-CSCFs, thereby to cause the UE to establish the IMS connection (see Claim 1 rejection above).
As per claim 15, Agarwal and Noldus teach a non-transitory computer-readable medium storing instructions that, when executed by at least one processor of a first network node in a telecommunications network, cause the first network node to perform operations (see Agarwal, [0047]: "The method may be embodied as a computer program product including a non-transitory computer readable medium (e.g. one or more memory elements) and instructions stored in the computer readable medium, where the instructions are executable on one or more processors for performing the steps of the method. In some implementations, the instructions stored in the one or more memory elements may be executable on the one or more processors for operation as a UPF.") comprising:
receiving a registration request at a first network node of the telecommunication network, the registration request including a request from a user equipment (UE) to establish an Internet Protocol (IP) Multimedia Subsystem (IMS) connection (see Claim 1 rejection above);
in response to the registration request, resolving a health status for each P-CSCF of a plurality of candidate P-CSCFs (see Claim 1 rejection above); and
after resolving the health statuses, transmitting at least one P-CSCF IP address to the UE based on the resolved health statuses of the plurality of candidate P-CSCFs, thereby to cause the UE to establish the IMS connection (see Claim 1 rejection above).
DEPENDENT:
As per claim 2, which depends on claim 1, Agarwal and Noldus further teach wherein resolving the health status includes: in response to the registration request: transmitting, from the first network node to a server of the telecommunications network, a query (see Agarwal, [0111], "In various example implementations, entities for various embodiments described herein can encompass network elements (which can include virtualized network elements, functions, etc.) such as, for example, network appliances, forwarders, routers, servers, switches, gateways, bridges, loadbalancers, firewalls, processors, modules, radio receivers/transmitters, or any other suitable device, component, element, or object operable to exchange information that facilitates or otherwise helps to facilitate various operations in a network environment as described for various embodiments herein"; and Claim 1 rejection above),
transmitting, from the server to the respective P-CSCF, a health check request (see Agarwal, Abstract: "In some implementations, the procedure may involve a session management function (SMF) programming of a user plane function (UPF) for UPF monitoring of the P-CSCF, using a ping procedure or health check procedure (e.g. for 3GPP Pre-Release 16). In other implementations, the procedure may involve the SMF monitoring of a P-CSCF via a Network Function (NF) Repository Function (NRF)"; [0041]: "For service discovery, NRF 132 may receive a discovery request from an NF instance and provide information associated with the discovered NF instance to the NF instance in response."; and [0053]: "Here, in step 418, UPF 120 may send a SIP OPTIONS message to query for operational status of P-CSCF-1 192."),
receiving, at the server from the respective P-CSCF, a health check response including a health indicator (see Agarwal, [0053]: "when the service of P-CSCF-1 192 is available, P-CSCF-1 192 may send back to UPF 120 a 200 OK message, where UPF 120 detects that P-CSCF-1 192 is reachable (step 421 of FIG. 4)."; and [0054]: "UPF 120 may employ a monitoring status update procedure (step 430 of FIG. 4) to report host availability status and/or loss status to SMF 118"), and
resolving the health status of the respective P-CSCF based on the health indicator (see Agarwal, [0023]: "The message may trigger, at the SMF, an initiation of an address list update procedure for a reselection of a new application or control function of the network for the voice or data service by the one or more UEs."; [0026]: "Based on receiving the message for reporting the failure, the SMF may initiate initiating a second address list update procedure for a reselection of a second new application or control function of the second network for the voice or data service. The one or more UEs may be a plurality of UEs which are updated with new address information for the voice or data service."; and [0054]: "The message may be used for triggering an initiation of an address list update procedure with UE 102 and other UEs (step 432 of FIG. 4), for a reselection of a new P-CSCF for the service by UE 102 as well as the other UEs. The reselection may be performed with use of a procedure for session release with reactivation (step 434 of FIG. 4). ").
Agarwal do not explicitly teach that the server is a DNS server, and the query is a DNS query.
Noldus teaches a DNS server and a DNS query (see Noldus, [0012]: " It is possible that the step of deriving comprises performing a Domain Name Server (DNS) query on the basis of the group identifier. The DNS may for example return a list of Internet Protocol (IP) addresses corresponding to the second nodes of the plurality of second nodes. The first node may then select one of the IP addresses").
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the invention to modify the system of Agarwal in view of Noldus so that server is a DNS server and the query is a DNS query. One would be motivated to do so because Agarwal teaches in paragraph [0114], "a module, engine, client, controller, function, logic or the like as used herein in this Specification, can be inclusive of an executable file comprising instructions that can be understood and processed on a server, computer, processor, machine, compute node, combinations thereof, or the like and may further include library modules loaded during execution, object files, system files, hardware logic, software logic, or any other executable modules".
As per claim 3, which depends on claim 1, Agarwal and Noldus further teach wherein resolving the health status includes:
transmitting, from the first network node to a domain name system (DNS) server of the telecommunications network, a DNS query (see Claim 2 rejection above);
at predetermined intervals: transmitting, from the DNS server to the respective P-CSCF, a health check request (see Claim 2 rejection above),
receiving, at the DNS server from the respective P-CSCF, a health check response including a health indicator (see Claim 2 rejection above), and
storing the health indicator in a memory of the DNS server (see Agarwal, [0024]: "The SMF may invoke a failure detection monitoring procedure for monitoring the application or control function associated with address information which is stored at the SMF."; [0071]: "Beginning at a start block 502, the SMF may invoke a failure detection monitoring procedure for monitoring the application or control function associated with address information which is stored at the SMF (step 504 of FIG. 5A). In step 504, invoking the failure detection monitoring procedure may involve subscribing to notification of the NRF based on the address for identifying failure of the application or control function (step 506 of FIG. 5A)."; and Claim 2 rejection above); and
in response to the registration request, resolving the health status of the respective P-CSCF based on the stored health indicator (see Claim 2 rejection above).
As per claim 4, which depends on claim 1, Agarwal and Noldus further teach wherein transmitting the at least one P-CSCF IP address includes: based on the resolved health statuses, determining a primary P-CSCF and a secondary P-CSCF of the plurality of candidate P-CSCFs (see Agarwal, [0074]: "In step 524, invoking the failure detection monitoring procedure may involve sending, to the UPF, a message for configuring the second address information of the second application or control function in the UPF, so that the UPF is enabled to regularly perform a ping procedure (or health check procedure) with the second application or control function using the second address information (step 526 of FIG. 5B). In the failure detection monitoring procedure, the SMF may receive, from the UPF, a message for reporting a failure of the second application or control function (step 528 of FIG. 5B). Based on the receiving the message for reporting the failure, the SMF may initiate an address list update procedure for a reselection of a new application or control function of the network for the voice or data service by the one or more UEs (step 530 of FIG. 5B)"); and
transmitting a primary P-CSCF IP address and a secondary P-CSCF IP address to the UE (see Agarwal, [0005]: "To establish service, a user equipment (UE) may receive a P-CSCF address of the P-CSCF in a message which includes a Protocol Configuration Options (ePCO) container. During operation, the P-CSCF may fail and, as a result, service may become unavailable."; and [0026]: "Again, an SMF may maintain access to stored information for a plurality of selected application or control functions, and these selected application or control functions may include first and second application or control functions.").
As per claim 6, which depends on claim 1, Agarwal further teaches wherein the IMS connection is a Voice over New Radio (VoNR) or Voice over Long-Term Evolution (VoLTE) connection (see Agarwal, [0004]: "In a Fifth Generation (5G) network, a Voice over New Radio (VoNR) service may be offered. VoNR provides significantly lower latency and improved sound & picture quality, resulting in an extremely elevated calling experience. An SP mobile operator would like to ensure that services, such as VoNR, are provided with high availability and reliability. Given that service failures may occur, an efficient service failure detection and restoration should be considered.").
As per claim 7, which depends on claim 1, Agarwal further teaches wherein the first network node is associated with a Session Management Function (SMF) of the telecommunications network (see Agarwal, Abstract: "The application or control function may be a Proxy-Call Session Control Function (P-CSCF) of the IMS network. In some implementations, the procedure may involve a session management function (SMF) programming of a user plane function (UPF) for UPF monitoring of the P-CSCF, using a ping procedure or health check procedure (e.g. for 3GPP Pre-Release 16). In other implementations, the procedure may involve the SMF monitoring of a P-CSCF via a Network Function (NF) Repository Function (NRF) (e.g. for 3GPP Release 16).").
As per claim 9, which depends on claim 8, Agarwal and Noldus teach further comprising: at least one second processor in communication with a second network node of the telecommunications network; and a second memory storing second instructions executable by the at least one second processor, wherein the first instructions, when executed by the at least one first processor, further cause the first network node to, in response to the registration request: transmit, to the second network node, a DNS query, and wherein the second instructions, when executed by the at least one second processor, cause the second network node to: transmit, to the respective P-CSCF, a health check request, and receive, from the respective P-CSCF, a health check response including a health indicator (see Claim 2 rejection above).
As per claim 10, which depends on claim 8, Agarwal and Noldus teach further comprising: at least one second processor in communication with a second network node of the telecommunications network; and a second memory storing second instructions executable by the at least one second processor, wherein the first instructions, when executed by the at least one first processor, further cause the first network node to, in response to the registration request: transmit, to the second network node, a DNS query, and wherein the second instructions, when executed by the at least one second processor, cause the second network node to, at predetermined intervals: transmit, to the respective P-CSCF, a health check request, receive, from the respective P-CSCF, a health check response including a health indicator, and store the health indicator in the second memory (see Claim 3 rejection above).
As per claim 11, which depends on claim 8, Agarwal and Noldus further teach wherein transmitting the at least one P-CSCF IP address includes: based on the resolved health statuses, determining a primary P-CSCF and a secondary P-CSCF of the plurality of candidate P-CSCFs; and transmitting a primary P-CSCF IP address and a secondary P-CSCF IP address to the UE (see Claim 4 rejection above).
As per claim 13, which depends on claim 8, Agarwal and Noldus further teach wherein the IMS connection is a Voice over New Radio (VoNR) or Voice over Long-Term Evolution (VoLTE) connection (see Claim 6 rejection above).
As per claim 14, which depends on claim 8, Agarwal and Noldus further teach wherein the first network node is associated with a Session Management Function (SMF) of the telecommunications network (see Claim 7 rejection above).
As per claim 16, which depends on claim 15, Agarwal and Noldus teach wherein resolving the health status includes: in response to the registration request: transmitting, from the first network node to a domain name system (DNS) server of the telecommunications network, a DNS query, causing the DNS server to transmit, to the respective P-CSCF, a health check request, causing the DNS server to receive, from the respective P-CSCF, a health check response including a health indicator, and resolving the health status of the respective P-CSCF based on the health indicator (see Claim 2 rejection above).
As per claim 17, which depends on claim 15, Agarwal and Noldus teach wherein resolving the health status includes: transmitting, from the first network node to a domain name system (DNS) server of the telecommunications network, a DNS query; at predetermined intervals: causing the DNS server to transmit, to the respective P-CSCF, a health check request, causing the DNS server to receive, from the respective P-CSCF, a health check response including a health indicator, and causing the DNS server to store the health indicator in a memory of the DNS server; and in response to the registration request, resolving the health status of the respective P-CSCF based on the stored health indicator (see Claim 3 rejection above).
As per claim 18, which depends on claim 15, Agarwal and Noldus further teach wherein transmitting the at least one P-CSCF IP address includes: based on the resolved health statuses, determining a primary P-CSCF and a secondary P-CSCF of the plurality of candidate P-CSCFs; and transmitting a primary P-CSCF IP address and a secondary P-CSCF IP address to the UE (see Claim 4 rejection above).
As per claim 20, which depends on claim 15, Agarwal further teaches wherein the first network node is associated with a Session Management Function (SMF) of the telecommunications network (see Claim 7 rejection above).
7. Claims 5, 12, and 19 are rejected under 35 U.S.C. 103 as being unpatentable over Agarwal et al. (US 2023/0362210 A1) and Noldus (US 2012/0185613 A1), and still further in view of Westman et al. (US 2004/0057442 A1).
As per claim 5, which depends on claim 1, although Agarwal explicitly teaches a server resolving the at least one P-CSCF IP address (see Claim 2 rejection above), Agarwal and Noldus do not explicitly teach further comprising: receiving a fully qualified domain name (FQDN); and resolving based on the FQDN.
Westman teaches receiving a fully qualified domain name (FQDN) (see Westman, [0037]: "The service providers have associated with them a FQDN (Fully Qualified Domain Name). In addition to the service provider domain names, the list contains two defaults: home_proxy and visited_proxy."); and resolving based on the FQDN (see Westman, [0042]: "Preferably, DNS at the access network is used to resolve the FQDNs (Fully Qualified Domain Name) to IP addresses"; and [0075]: "DNS at the access network is used to resolve the FQDNs (Fully Qualified Domain Name) to IP addresses.").
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the invention to modify the system of Agarwal and Noldus in view of Westman by implementing receiving a fully qualified domain name (FQDN); and resolving based on the FQDN. One would be motivated to do so because such an implementation provides a globally unique identifier to map network IP addresses with the DNS namespace, which is well-known, widely-implemented, routine, and conventional.
As per claim 12, which depends on claim 8, Agarwal, Nodus, and Westman teach wherein the first instructions, when executed by the at least one first processor, further cause the first network node to: receive a fully qualified domain name (FQDN); and resolve the at least one P-CSCF IP address based on the FQDN (see Claim 5 rejection above).
As per claim 19, which depends on claim 15, Agarwal, Nodus, and Westman teach the operations further comprising: receiving a fully qualified domain name (FQDN); and resolving the at least one P-CSCF IP address based on the FQDN (see Claim 5 rejection above).
Conclusion
8. For the reasons above, claims 1-20 have been rejected and remain pending.
9. Any inquiry concerning this communication or earlier communications from the examiner should be directed to MICHAEL Y WON whose telephone number is (571)272-3993. The examiner can normally be reached on Wk.1: M-F: 8-5 PST & Wk.2: M-Th: 8-7 PST.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Nicholas R Taylor can be reached on 571-272-3889. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/Michael Won/Primary Examiner, Art Unit 2443
Prosecution Insights