CDM-570/570L Satellite Modem with Optional IP Module Revision 4
IP Module Ethernet Interface Overview MN/CDM570L.IOM

15.4.1 3xDES Encryption with Ability to Change Keys

The IP Module optionally supports 3xDES-128 (using NIST certified 3x core) encryption
and decryption, for the highest level security for link encryption. Each unit supports eight
encryption keys and eight decryption keys. The keys are user configurable. Each route
can be assigned to be encrypted by any of the eight available keys, random key method,
or transmitted in clear.

15.4.2 IP Header Compression

Header Compression is also an optional feature of the IP Module. The IP Module
supports Header Compression for the following Ethernet and Layer 3, 4 & 5 Headers:
Supported Ethernet Headers
Ethernet 2.0
Ethernet 2.0 + VLAN-tag
Ethernet 2.0 + MPLS
802.3-raw
802.3-raw + VLAN-tag
802.3 + 802.2
802.3 + 802.2 + VLAN-tag
802.3 + 802.2 + SNAP
802.3 + 802.2 + SNAP + VLAN-tag
802.3 + 802.2 + SNAP + MPLS
Supported Layer 3&4 Headers
IP
TCP
UDP
RTP (Codec Independent)
Header Compression reduces the required VoIP bandwidth by 60 percent. Example: A
G.729a voice codec, operating at 8 kbps, will occupy 32 kbps once encapsulated into IP
framing on a LAN. Using IP/UDP/RTP Header Compression, the same traffic only needs
10.8 kbps total WAN satellite bandwidth to cross the link. A total maximum of 64
simultaneous VoIP calls can be compressed. Normal Web/HTTP traffic can be reduced
an additional 10% via IP/TCP header compression.
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