Mocomtech CIM-550 Manuel D’Utilisation

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CiM-550 IP Enabled Satellite Modem 
Rev. 2 
Introduction 
CD/CIM550.IOM 
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.