HP 200 Series Services And Applications page 66

Bridging Service
Token Ring Solutions
Limitations An SRT bridge does not, however, provide communica-
tion between a source-routing system on one ring and a non-source-
routing system on another ring.
There are some basic differences at the MAC layer between token ring/IEEE
802.5 and Ethernet. As a result of these differences, the SRT bridge does not
support bridging between systems on dissimilar LANs. Traffic between
systems located on token ring LANs, therefore, cannot be bridged to systems
on Ethernet/IEEE 802.3 LANs.
Bridging in Mixed-Media Networks
Differences Between Token Ring and Ethernet Addressing
IEEE 802.5 token ring networks (and FDDI) differ from Ethernet networks
in the transmission order of bits in each octet. Ethernet nodes always
transmit the least-significant bit of a byte first. Token ring nodes always
transmit the most-significant bit of a byte first (see figure 6). The problem
this poses for bridging is in the interpretation of station addresses. Problems
in interpreting station addresses arise in a couple of different ways.
Figure 6. Ethernet/Token Ring Bit Order Differences
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