Header Compression - Paradise Datacom Vision Series Installation And Operating Handbook

Vision Series Installation and Operating Handbook
Static Route Configuration Screen
Each route consists of a Destination IP Address, Subnet Mask and a Gateway Address.
There is a checkbox for each route that enables the route w hen checked. Note that
Paradise does not recommend using DHCP to allocate the modem an M&C IP address
when static routes are being used.
7.4.14 Header Com pression
IP, UDP and RTP header compression is supported in accordance w ith the Robust
Header Compression (ROHC) standard RFC 3095 (profiles 2 and 3). ROHC typically
reduces the 40 bytes of IP, UDP and RTP header, w hich is typically used w ith Voice over
IP data, dow n to between 1 and 3 bytes. Ethernet header compression is also supported
in addition and this reduces 14 bytes of Ethernet frame dow n to typically 1 byte. Overall
savings from compression from both types of compression (e.g. for a G.729 voice stream)
can be as high as 60%.
It is w idely acknow ledged that ROHC is the most suitable available header compression
technology for use over satellite and outperforms older technologies such as Compressed
Real Time Protocol (CRTP) and IP Header Compression (IHCP).
Note that because the header compression is applied only over the satellite portion of the
link and results in the original packets being recreated upon receipt, the compression
process is completely transparent.
It is possible to specify w hi c h data streams (routes) compression should be applied to –
see the screenshot overleaf. Each route consists of a Destination IP Address and Subnet
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