What is P-CSCF and S CSCF?

The Call Session Control Function (CSCF) in IMS comprises three distinct roles: the Proxy CSCF (P-CSCF), the Interrogating CSCF (I-CSCF), and the Serving CSCF (S-CSCF). The CSCF is implemented via servers using the SIP protocol to communicate with each other and application servers.

What is P-CSCF in LTE?

A Proxy-CSCF (P-CSCF) is a SIP proxy that is the first point of contact for user equipment in an mobile network All SIP traffic to and from the user equipment must go through the P-CSCF. Private Mobile Network (PMN) << Previous.

What is the significance of P-CSCF?

The Proxy-Call Session Control Function (P-CSCF) is the first contact point for the users of the IP Multimedia Subsystem (IMS). The P-CSCF functions as a proxy server for the user equipment; all Session Initiation Protocol (SIP) signaling traffic to and from the user equipment must go through the P-CSCF.

What are the S CSCF capabilities?

S-CSCF selection based on capabilities utilizes AVP information exchanged with the HSS to identify required and preferred capabilities on a per-user basis. Capabilities themselves vary widely. Examples include administrator routing preferences for divergent service types.

What is P-CSCF in 5G?

Proxy-Call Session Control Function (P-CSCF) discovery performed by the device during IMS signaling flow establishment is supported by 5G Session Management Function (SMF). • The P-CSCF in IMS may continue to use the Rx interface to the 5G Policy Control Function (PCF).

What is P-CSCF address?

The P-CSCF is the single entry point for all SIP messages that are sent from Tobias’s UE to the IMS. Therefore, the P-CSCF address needs to be known by the UE before the first SIP message is sent. As this address is not pre-configured in our example, it needs to be discovered by the UE.

What is SAR in IMS?

After the S-CSCF successfully authenticates the user, it informs the HSS through Server-Assignment-Request (SAR) and Server-Assignment-Answer (SAA) Diameter messages which user it is serving. Subsequently, the HSS creates a mapping between the user and the S-CSCF.

What is P-CSCF discovery?

10.3. P-CSCF discovery. The P-CSCF is the single entry point for all SIP messages that are sent from Tobias’s UE to the IMS. Therefore, the P-CSCF address needs to be known by the UE before the first SIP message is sent. As this address is not pre-configured in our example, it needs to be discovered by the UE.

What is IMS architecture?

IP Multimedia Subsystem or IMS is a standards-based architectural framework for delivering multimedia communications services such as voice, video and text messaging over IP networks.

What is AGCF in IMS?

The Access Gateway Control Function (AGCF) allows for legacy non-SIP networks to receive communication from an IMS network via a Media Gateway or Softswitch. The AGCF when working with a Media Gateway, a Call Session Controller, and Application Server function as a SIP agent within an IMS network.