IP Over CCSDS Exchange Machenism Approach

Thanks to the advances in satellite and internet technology, the constellation of satellites becomes the focus of the satellite communication areas, and next-gereration satellite network will provide broadband, packet-switched sevices. The space-ground internet that includes satellite network and ground network and exchanges data from each other, are attractive. However, because of the differences of the satellite and ground network, the protocols that are already mature in the ground network cannot completely move to the satellite network. The satellite network needs its own protocols. Then the satellite network and the ground network use different protocols, it must use some exchange machenism to solve this problem. In this circumstance, the satellite-ground gateway is introduced.TCP/IP protocol suit is widely used in ground network, and it is already the standard in fact. But it must be modified to adapt to the satellite network. And in data link layer, CCSDS that designed by Consultative Committee for Space Data Systems is used more and more frenquently in satellite links.In this paper, a satellite-ground gateway that is used between ground IP network and satellite IP network based on CCSDS is introduced. The topics discuss here include the datagram's sending and receiving, address resolution and IP fragmation and recombination etc. The algorithms about encapsulating IP datagram into CCSDS frame and extracting IP datagram from CCSDS frame are introduced. And the strategy of routing and multicasting are also discussed.