Mocomtech CIM-550 - Manual (Page 30)

CiM-550 IP Enabled Satellite Modem Rev. 2
Introduction CD/CIM550.IOM
4
1.4 O PTIONS
Enhancing the CiM-550’s performance is easy. Additional features can be added quickly
on site, using the FAST access code purchased from Comtech EF Data. To enable these
features, simply enter the code at the front panel.
Description Software Version
Turbo Product Coding (TPC) 1.0.1 and Later
TCP acceleration Future
DES Data Encryption 1.0.1 and Later
IP Datagram Compression Future
IP Header Compression Future
Quality of Service (QoS) 1.0.1 and Later
Network Address Translation (NAT) Future
EasyConnect
 for non-IP traffic Future
IGMP support for multicast 1.0.1 and Later
1:1 Redundancy with CRS-100 1.0.1 and Later
1.4.1 T
URBO
P
RODUCT
C
ODING
(TPC)
The optional Turbo Product Coding (TPC) is a recent development in FEC techniques
that delivers significant performance improvements when compared to Viterbi with
concatenated Reed-Solomon. TPC simultaneously offers increased coding gain,
markedly lower decoding delay (leading to improved TCP/IP performance), and
bandwidth savings of up to 40%. The TPC option includes two modes (BPSK 22/44 and
BPSK 5/16) that permit operation from exceptionally small antennas, where flux density
issues are of concern.
1.4.2 TCP A
CCELERATION
To compensate for the TCP performance degradation in a high delay and high BER (Bit
Error Rate) environment, the CiM-550 incorporates an optional proprietary transparent
TCP acceleration mechanism that will allow a TCP session to optimally use the available
link capacity, while preserving end-to-end transport reliability. TCP acceleration will be
subject to user configured Quality of Service (QoS) restrictions for the route.
1.4.3 DES E
NCRYPTION WITH
A
BILITY TO
C
HANGE
K
EYS
The CiM-550 optionally supports DES-56 encryption and decryption. Each unit supports
2 encryption keys and 2 decryption keys. The keys are user configurable. Each route can
be assigned to be encrypted by key 1 or key 2 or transmitted in clear.