IMS S-CSCF Serving Call State Control Function

- details for the function, operation and implementation of the IMS S-CSCF, Serving Call State Control Function.

The IMS S-CSCF, or Serving Call State Control Function, is one of the major entities within the overall IMS architecture.

The IMS S-CSCF is at the core of many functions within an IMS network, communicating with many other functions within the overall system.

The S-CSCF undertakes a variety of actions within the overall system, and it has a number of interfaces to enable it to communicate with other entities within the overall system.

IMS S-SCSF basics

The Serving Call State Control Function, S-CSCF, is the main SIP session control node within the overall IMS network.

When a subscriber enters the network, the subscriber provides a contact address and a public user identity. This is provided to the S-CSCF.

These two elements of data are then linked in a process known as binding.

In view of its role within the IMS network, the S-CSCF is seen as the registrar for the network, although the HSS holds the data against which the S-CSCF checks the authenticity of the subscriber requesting entry.

S-CSCF interfaces

The S-CSCF interfaces with several other entities within the IMS network.

A diagram shwoing the IMS S-CSCF or Serving Call State Control Function interfaces
IMS S-CSCF Interfaces

By Ian Poole

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Next Generation Freight Transport Mark Patrick | mouser Electronics
Next Generation Freight Transport
As road freight transport levels continue to grow, concerns about the impact on the environment and human health come sharply into focus. Fossil fuel dependency makes it a leading source of greenhouse gas (GHG) emissions, but shifting freight to other transportation modes will prove challenging. Solutions that will improve the efficiency and performance of road freight transport are therefore essential to achieve defined environmental goals. In this blog, we will explore a potential solution that has been pioneered by Siemens - called eHighway. This combines the efficiency of electrified railways with the flexibility of trucks in order to form an innovative, next generation freight traffic system that is efficient, economical and environmentally friendly. is operated and owned by Adrio Communications Ltd and edited by Ian Poole. All information is © Adrio Communications Ltd and may not be copied except for individual personal use. This includes copying material in whatever form into website pages. While every effort is made to ensure the accuracy of the information on, no liability is accepted for any consequences of using it. This site uses cookies. By using this site, these terms including the use of cookies are accepted. More explanation can be found in our Privacy Policy