Comtech EF Data CDD-56X Series Vipersat - Manual (Page 21)

Chapter 1 - General 1-7
MN/22137, rev 1 Product Description
Payload Decompression
Payload compression condenses the size of data frames and reduces the satellite
bandwidth required to transmit across the link. Configurable on a per route
basis, Payload Compression provides traffic optimization and reduces band-
width up to 40%. The CDD-56X demods perform payload decompression prior
to passing the data onto the LAN.
Data Decryption
The CDD-56X decrypts 3xDES data that it receives. Data encryption, configu-
rable on a per route basis, is used to prevent unauthorized access to data over the
satellite link.
New in This Release
The following firmware version incorporates a number of additional features
and enhancements.
1.6.11/2.6.11 Release
Dynamic Entry Channel Mode
Dynamic ECM (ECMv2) utilizes a modified slotted Aloha method for Remotes
to establish registration in the network and obtain the means for switching into
dSCPC mode. Rather than sharing an STDMA burst map, as is the method with
STDMA ECM, the Remotes rely on communicating with the Hub channel
controller through the use of a multicast Transmission Announcement Protocol
(TAP) message. This eliminates the restriction in the number of Remotes in an
Entry Channel group that is inherent with the burst map method.