NSIS Extensions: An End-to-End QoS Aware Signaling Protocol for NGN

NGN. We will look into IETF's efforts on developing signaling protocols in satisfying the ever demanding end-to- end guaranteed QoS needs by end users or interconnected network nodes. A comparative study is done for Integrated Services (IntServ), Differentiated Services (DiffServ), Resource Reservation Protocol (RSVP), and the newly developed Next Steps in Signaling (NSIS) as QoS signaling protocol and NSIS possible extensions. Index Terms—QoS, NGN, RSVP, NSIS, QoS NSLP. such signaling was to provide and control information about data flow along its path during network transmission. A study on requirement of such architecture was presented in (3). The key goals of NSIS could be summarised as: information availability - when and where needed; creating a modular design to allow future extensions; decoupling of protocol and information layer - which means work with routers that support NSIS and ignore the rest. This paper will mainly look into the achievements of IETF in developing end-2-end QoS aware signaling architecture and its further extensions like QoS NSLP, QSPEC Template etc. A review on signaling and QoS signaling need will be presented, looking at the work done for standardisation of such protocols by IETF and ITU-T. We will also compare the key differences of IntServ, DiffServ, RSVP, NSIS and its extensions' architecture. The rest of the paper is organised as follows: Section-II will discuss the background studies on signaling protocols for communications. Section-III will present literature survey on IETF' and ITU-T standardization efforts on NGN architecture and signaling protocols. In Section-IV we will compare the architectural differences and services offered by the protocols developed so far for IP based internet telephony (e.g. VoIP) and multimedia. In Section-V we will present a critical analysis of possible NSIS extensions. Finally, we will give conclusion of our paper in Section-VI.