CDM-570/570L Satellite Modem with Optional IP Module Revision 4
IP Module Ethernet Interface Overview MN/CDM570L.IOM
IMPORTANT
easyConnect™ mode will automatically use Header Compre ssion for compressing
Layer 2 (even if Header Compression option has not been purchase d). Because of
this, some of the initial traffic sent between two devices will not be received over the
satellite until a full Header is transmitted. For example, the default Header
Compression Refresh Rate is 50 packe t s. If a ping is sent over the satellite, then it
will time out until the full Header packet is sent. The Header Compression Refresh
Rate on the Administration Menu can be reduced to minimize the amount of traffic
lost when traffic is first sent between two devices. Once communication between two
devices has been established, both IP modems will be able to receive all traffic,
unless one IP modem is power cycled or reset. Header Compression feature should
be enabled for compre ssing Layer 3, Layer 4 and Layer 5.
IMPORTANT
Do not enable IF Loopback (or link the TX to RX by a BNC cable or satellite) on a IP
modem operating in easyConnect™ mode when connected to a LAN. In this
configuration, easyConnect™ will resend all layer 2 broadcast packets and caus e a
“broadcast storm” on the L A N. To perform a loop test to verify the modem or satellite
link, do one of the following:
1. Reconfigure the CDM-570/570L interface selection by selecting
Configuration/Interface and then selecting EIA-422/530, V.35, or EIA-232.
OR
2. Set the
IP Module to Router Mode.

15.4 IP Module Optional Features

Enhancing the IP Module 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.
• 3xDES Data Encryption
• IP Header Compression
• Payload Compression
• Quality of Service (QoS) – supports 3 different modes of QoS
• Minimu m/Maximum Bandwidt h
• Maximum Bandwidth/Priority
• DiffServe
IMPORTANT
Note: Enabling the Demo Mode from th e front panel can temporarily enable all IP
FAST Options (except 3xDES Encryption) for evaluation. Once enabled, the IP
FAST Options will be available for a total time period of seven (7) days (168
hours). The 7-day Demo Mode is a cumulative counter (can be stopped and
started at any time).
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