This document describes functions implemented in Session Initiation Protocol (SIP) intermediaries known as Session Border Controllers (SBCs). The goal of this document is to describe the commonly provided functions of SBCs. A special focus is given to those practices that are viewed to be in conflict with SIP architectural principles. This document also explores the underlying requirements of n...

The prevalent use of the Session Initiation Protocol (SIP) in Next Generation Networks necessitates that SIP networks provide adequate control mechanisms to maintain transaction throughput by preventing congestion collapse during traffic overloads. A loss-based solution to remedy known vulnerabilities of the SIP 503 (Service Unavailable) overload control mechanism has already been proposed. Usi...

Session Initiation Protocol (SIP) is an application layer protocol designed to control and establish multimedia sessions over internet. SIP gaining more and more popularity as it is used by numerous applications such as telephony over IP (ToIP). SIP is a text based protocol built on the base of the HTTP and SMTP protocols. SIP suffers from certain security threats which need to b e resolved in ...

The Session Initiation Protocol (SIP) was developed to control multi-media sessions on the Internet. Shortly after its debut as a standard in 1999, SIP was adopted by the 3rd Generation Partnership Project (3GPP) as the preferred signaling protocol for the Internet Multimedia Subsystem (IMS). This adoption provided a boost to the nascent protocol as traditional telecommunication services were i...

This article discusses technical issues related to delivery and control of IP multimedia services, such as videoconferencing, involving heterogeneous end terminals. In particular, it describes the design and implementation of an experimental system for interworking between IETF SIP (Session Initiation Protocol) and ISO MPEG-4 DMIF (Delivery Multimedia Integration Framework) session and call con...

It is desirable to integrate 3G Universal Mobile Telecommunication System (UMTS) and 802.11 wireless local area networks, especially at hot-spot locations such as hotels and airports. The efficiency of wireless data services can be maximized if the integration provides users with seamless roaming across the two types of networks. Seamless handoff between these two networks to maintain session c...

The prevalent use of the Session Initiation Protocol (SIP) in Next Generation Networks necessitates that SIP networks provide adequate control mechanisms to maintain transaction throughput by preventing congestion collapse during traffic overloads. A loss-based solution to remedy known vulnerabilities of the SIP 503 (Service Unavailable) overload control mechanism has already been proposed. Usi...

Mobile ad hoc networks (MANETs) are of primary interest as new networks because of their flexibility. The Session Initiation Protocol (SIP) is the main signaling system in 3G and SIP servlets the main service provisioning framework. SIP is now being considered as a basis for signaling in MANETs. This makes the SIP servlets framework a chief candidate for service provisioning in MANETs. In this ...

Internet telephony is receiving increasing interest as an alternative to traditional telephone networks. This article shows how the IETF’s Session Initiation Protocol (SIP) can be used to perform the services of traditional Intelligent Network protocols, as well as additional services.

In today′s communications over Internet Protocol (IP), Session Initiation Protocol (SIP) is using establish, modify and terminate the sessions multimedia among participants. Authentication is the most security service required for SIP. Authentication HTTP Digest is the original authentication protocol proposed for SIP. However, this protocol is demonstrated insecure against different attacks. T...