IP Multimedia Subsystem (IMS) Emulator

Overview

Internet Protocol (IP) Multimedia Subsystem, popularly known as "IMS", is built on Session Initiation Protocol (SIP) to further support packaging of voice, video, data, fixed, and mobile services on a single platform to users. It provides a unique convergence platform for different types of networks – whether it is mobile, satellite, broadband, cable and fixed networks, with the goal of building an efficient interoperating network.

GL’s MAPS™ IMS test suite provide a full-fledged network environment that enables users to test their applications, devices, and services prior to deployment on a real-time network. It can emulate all or specific elements within IMS network infrastructure using simple ready-to-use testbed setups.

The application is available as:

• MAPS™ IMS Protocol Emulator (Item # PKS127)

The network architecture shown above outlines the IMS Core Network elements which can be simulated using GL's MAPS™ IMS test tool.

MAPS™ IMS test suite can emulate multiple UEs and IMS core elements such as P-CSCF, I-CSCF, S-CSCF, PCRF, MGCF and IP-SM-GW which provides the IMS core network. With the help of mobile phones, and other emulated wireless networks, the VoLTE or VoNR lab can be operated in real-time for making VoLTE or 5G New Radio, SMS calls and also for interworking with PSTN and VoIP networks.

Few of the IMS network entities and their functionalities are:

• P-CSCF – Receives requests from UE and then serves the request or forwards it to other servers
  • A SIP proxy
  • First point of contact for the IMS terminal
  • Discovers its P-CSCF
  • Locates I-CSCF for the user
  • Provides subscriber authentication
• I-CSCF – Acts as contact point in the operator’s network
  • Forwards SIP request or response to the S-CSCF
  • Used for SIP functions such as Registration
• S-CSCF – Maintains sessions for the registered users
  • Central node of the signaling plane
  • Handles SIP registrations, routing services, enforces the policy
• IP-SM-GW (IP Short Message Gateway) –
  • Network element provides the interconnection between GSM-UMTS network and LTE-EPC network for sending and receiving SMS.

MAPS™ can be used to emulate all of the interfaces listed above in an IMS network. A single MAPS™ can act as more than one entity at a time and generating required messages in the network.

MAPS™ IMS Emulator includes ready-to-use scripts, as per IETF specification. The test scripts include general messaging and call flow scenarios for multimedia call session setup and control over IP networks. Reports are logged in for pass/fail test scenarios. Test cases verify conformance of user equipments (UEs), proxies, registrar and redirect server functionalities.

The application gives the users the unlimited ability to edit protocol specific messages and control scenarios (message sequences). "Message sequences" are generated through scripts. "Messages" are created using message templates.

GL’s IMS Protocol Analyzer within PacketScan™- All IP Protocol Analyzer is capable of real-time capturing, decoding and analyzing SIP signaling and RTP media for live systems as well as the Diameter signaling used for accessing subscriber data and charging data on IMS networks.