3Com PathBuilder S200 Series, Owner'S Manual

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46 Bridging
Configuring the PathBuilder S200 Series Switch for Bridging Operation
8) The server issues a Specific Route TEST frame (also called a non-broadcast
frame) in response using the route indicated in the ARE TEST frame. Note that
the server does not have to broadcast (use ARE) to get the TEST response back to
the PC; it uses a Specifically Routed TEST frame (Figure 26).
Figure 26. Server Responds with Specifically Routed TEST Frame
9) The response TEST frame also has a Routing Information Field (RIF) with the
same path trace as the original ARE TEST frame except the Direction bit is set to
1. This reverses the direction in which the RIF sequence is read and indicates the
path back to the source. The RIF also sets three bits in the Routing Type field that
indicate the frame is to be specifically routed and not broadcast.
10) When the response TEST frame reaches the source PC, the PC now knows what
route to use to send its frames to the server.
LAN
Port
WAN
Adaptor
5
6
7
1
LAN
Port
WAN
Adaptor
5
6
7
1
PB S200
Bridge
Bridge
WAN
Network
PC
Server
LAN
AAA
LAN
CCC
PB S200