Comtech EF Data CIM-550, Инструкция по установке и эксплуатации

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CiM-550 IP Enabled Satellite Modem Rev. 2
Introduction CD/CIM550.IOM
5
1.4.4 IP D
ATAGRAM
C
OMPRESSION
Optionally, the CiM-550 supports IP datagram compression to provide improved
bandwidth. IP payload is compressed while the IP Headers remain unaffected.
1.4.5 IP H
EADER
C
OMPRESSION
Optionally, the CiM-550 supports IP header compression to provide improved bandwidth
usage especially for smaller datagrams where the header overhead could be significant
(e.g. VoIP).
1.4.6 Q
UALITY OF
S
ERVICE
Quality of Service (QoS) is an optional feature of the CiM-550. A QoS can be assigned
to each route. It dictates the guaranteed minimum and allowable maximum data rate for
that route. The CiM-550 classifies the incoming traffic based on the destination address
and allocates bandwidth based on the configured profile.
1.4.7 N
ETWORK
A
DDRESS
T
RANSLATION
(NAT)
Optional NAT is a feature that allows a LAN to use private IP addresses for internal
communications and share a totally different IP address for external communications.
1.4.8 E
ASY
C
ONNECT

FOR NON
-IP
TRAFFIC
The CiM-550 optionally supports EasyConnect

to support non-IP traffic. This allows
the CiM-550 to simultaneously route IP traffic and bridge non-IP traffic, such as IPX.
The non-IP traffic will be subject to user configured QoS restrictions.
1.4.9 IGMP S
UPPORT FOR
M
ULTICAST
IGMP is an optional feature in the CiM-550. If enabled, it responds to IGMP queries for
the configured multicast routes on the transmit side and generates IGMP queries on the
receive side. If there are no active IGMP receivers on the LAN it will stop forwarding
the multicast traffic (received from the satellite) to the LAN.
1.4.10 1:1 R
EDUNDANCY
C
ONFIGURATION
The CiM-550 supports 1:1 redundancy in conjunction with the CRS-100 IF Switch. In a
redundant configuration the primary CiM-550 communicates with the backup CiM-550
for synchronization and status checks. If there is a failure of the primary unit, the
backup CiM-550 assumes the role of the primary modem with minimal disruption to the
traffic. The switchover is transparent to other devices on the LAN.