Presence Traffic Optimization Techniques

With the growth of presence-based services, it is important to provision the network to support high traffic and load generated by presence services. Presence event distribution systems amplify a single incoming PUBLISH message into possibly numerous outgoing NOTIFY messages from the server. This can increase the network load on inter-domain links and can potentially disrupt other QoS-sensitive applications. In this document, we present existing as well as new techniques that can be used to reduce presence traffic both in inter-domain and intra-domain scenarios. Specifically, we propose two new techniques: sending common NOTIFY for multiple watchers and batched notifications. We also propose some generic heuristics that can be used to reduce network traffic due to presence

Handling of IP-Addresses in the Context of Remote Access

Masteroppgave i informasjons- og kommunikasjonsteknologi 2008 – Universitetet i Agder, GrimstadFor various reasons (e.g., security, lack of IPv4-addresses) the services in the home smart space only use private IP addresses. This is unfortunate in the remote service access since these addresses frequently appear in responses sent from a service in the remote smart space (e.g., your home) to the visited smart space (e.g., your friend’s home).The Internet Engineering Task Force (IETF) provides some solutions and workarounds for the problem caused by NAT. In this project, the challenge to me is to summarize the available options, rank the options according to which one is preferred for the RA-scenario. I will come up with my practical NAT traversal techniques by testing and gathering data on the reliability of NAT traversal techniques since none of the existing ones seems to work well. A demonstration of the key features will be shown in the thesis. NAT traversal techniques apply to TCP and UDP need to be researched in advance. Handling of peers behind all kinds of NAT need to be tested and determined for the communication. The result of the paper will well improve the evaluation of specific issues on NAT and the creating of an UNSAF proposal

SIP based IP-telephony network security analysis

Masteroppgave i informasjons- og kommunikasjonsteknologi 2004 - Høgskolen i Agder, GrimstadThis thesis evaluates the SIP Protocol implementation used in the Voice over IP (VoIP) solution at the fibre/DSL network of Èlla Kommunikasjon AS. The evaluation focuses on security in the telephony service, and is performed from the perspective of an attacker trying to find weaknesses in the network. For each type of attempt by the malicious attacker, we examined the security level and possible solutions to flaws in the system. The conclusion of this analysis is that the VoIP service is exploitable, and that serious improvements are needed to achieve a satisfying level of security for the system