The TISPAN network architecture is based on 3GPP IMS, which is a basis for control and provision of the real-time conversation services (based on SIP protocol) [2], [9], [10]. 3GPP IMS architecture is extended in TISPAN NGN to support various types of access networks, such as xDSL, WLAN, etc.
TISPAN architecture is extended mainly by:
For services on other than SIP basis, the TISPAN NGN architecture can include other subsystems defined in TISPAN. Figure illustrates the NGN components and functionalities.