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WCM1100 / WCM3100 / WCM-Serial / LHM1000 / LVM2000 User Manual
76-02-082 Rev N
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5.3.8.4.1.2 Strip MAC FCS
A LAN packet is protected by a 32 bit FCS. Since the encapsulator will add an HDLC FCS
it is possible to save bandwidth by removing the Ethernet FCS and recalculate at the far
end.
Both ends of the link MUST match otherwise traffic will not flow, For operation with an
unmanaged WC product, or previous software version MAC FCS Stripping mode must be
used.
For greatest protection against errors, MAC stripping should be disabled and the frame
FCS sent end to end to protect against any internal errors. This requires extra overhead,
so it is a trade off between error protection and bandwidth.
5.3.8.4.1.3 Payload Scrambler
For security purposes and to ensure a good ones density an X^43 scrambler may be
applied
Both ends of the link MUST match otherwise traffic will not flow, For operation with an
unmanaged WC product, or previous software version the payload scrambling must be
disabled
5.3.8.4.2 X.86
The WCM offers X.86 LAPS encapsulation when used on a framed, byte synchronous
interface. X.86 uses flags to delimit and pad, and appends a four byte header to the
packet along with a 32 bit FCS. Additional options are:
5.3.8.4.2.1 Strip MAC FCS
A LAN packet is protected by a 32 bit FCS. Since the encapsulator will add an HDLC FCS
it is possible to save bandwidth by removing the Ethernet FCS and recalculate at the far
end.
Both ends of the link MUST match otherwise traffic will not flow.
5.3.8.4.2.2 Payload Scrambler
For security purposes and to ensure a good ones density an X^43 scrambler may be
applied. Both ends of the link MUST match otherwise traffic will not flow.
