SCPS-SP / IPSec Protocol Conversion Program Design And Implementation

Space/Ground network has been one important field of researches since more andmore space probes appeared. Space network is much different from ground networkbecause of some futures of satellite links including long time-delay, high bit error rate,asymmetric bandwidth and so on.CCSDS designed Space Communications Protocol Specification (SCPS) fit forsatellite links. SCPS has been developed from Internet TCP/IP model with a fewservices modified for space network. SCPS-SP included in SCPS is a security protocolbetween the second and the third layer like IPSec in Internet. SCPS-SP and IPSecprovide same services but are different from encapsulation and securiy policy. Tocomplete cooperation of SCPS-SP and IPSec, this article designes and implements theprotocol conversion in gateway between SCPS-SP and IPSec. Results of research arefollowing.Firstly, SCPS-SP does not specialize what is the method of key management for it.We designed SP-IKE key management system based on IKE protocol and theenvironment of space network. So, the protocol the protocol SCPS-SP can work better.Secondly, this article displays a resolution of the protocol conversion betweenSCPS-SP and IPSec. The article solves the problem that how transmited data isdecrypted and reencrypted with deep analysis and arrangement of two open sourcesoftware SCPS-RI and Openswan. As a result, we implement the conversion of differentencapsulations of SCPS-SP and IPSec.Finally, in this paper we document the implementation and test result of conversionbetween SCPS-SP and IPSec, using Openswan and SCPS-RI with SP-IKE on Linux inspace gateway. The results showed that one workable way to improve the transmitionsecury in Space/Ground network is the implementation of the protocol conversionbetween SCPS-SP and IPSec in space gateway.