HP 200 Series Services And Applications page 254

Using Synchronous Pass-Through to Consolidate Synchronous Traffic
How It Works
HOST A
HOST B
X.25 X.25
SITE B
SITE A
PACKET PACKET
SWITCH SWITCH
ROUTER ROUTER
TERM 1
PAD
ROUTER
SITE C
TERM 2
Figure 2. Bridging X.25 Traffic Using Sync Pass-Through
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