HP 600 Series, Services And Applications

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Bridging Over Frame Relay
The encoding of the NLPID field for bridged packets is the same as that used
for network layers not having a specific NLPID value—80 hex. This again
specifies a SNAP header; however, the encoding of the SNAP header is 00 80
C2, the organizational identifier of the IEEE 802.1 Committee. Table 5 shows
how a bridged frame is encoded.
Table 5. SNAP Header for Bridging
00 (hex)
IEEE 802.1
Organization
Code
80 (hex)
C2 (hex)
xx (hex)
Protocol ID
PID
xx (hex)
●
●
●
●
●
Complete
Bridged
Frame
The PID (Protocol ID) field identifies the media type and whether or not the
LAN FCS is appended to the bridged frame. The PID values are shown in
table 6.
Table 6. PID Values for Bridged Frames
With
Preserved FCS
Without
Preserved FCS Medium
00 - 01 00 - 07 802.3/Ethernet
00 - 02 00 - 08 802.4 (Token Bus)
00 - 03 00 - 09 802.5 Token Ring
00 - 04 00 - 0A FDDI
00 - 05 00 - 0B 802.6
00 - 0E Bridge BPDU
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Linking Up with Frame Relay
Frame Relay Data-Link Interface
3-95