A cross-layer framework for IPSec over satellite links

The traditional modular OSI-layered architecture has served a major role in the development of a variety of protocols. However, as physical layer impairments become complex and time varying, a dynamic crosslayer design can enable better performance. A Cross-Layer Architecture (CLA) is proposed to improve performance of error-tolerant applications running over UDP-Lite. This approach to implementation introduces new challenges in protocol design, as well as in the area of security, where the study proposes a new method to enable IP security (IPsec) authentication and integrity services at the network layer. Target scenarios include satellite multicast for large-scale delivery of data and video content. In this scenario, CLA can mitigate the effects of physical layer impairments and high latency. Numerical analysis has shown that a link design employing header compression and cross-layer signalling may protect protocol headers and can reduce the probability of packet discard. To evaluate the feasibility of the CLA, these methods have been implemented as an extension to the IPsec protocol, named Cross-Layer IPsec (CL-IPsec). A satellite emulation platform was used to validate the implementation of CL-IPsec and to evaluate the overall performance improvement resulting from the proposed CLA.