Command Reference Guide

268 ● pos-server fcm 3Com Router 5000 Family and Router 6000 Family
Command Reference
short duration setting may cause modem negotiation failures; on the router, the
modem port intermittently comes up/goes down and no data is transmitted or
received. In this case, you can increase the value of the answer timer.
■ After the negotiation succeeds, the two parties begin to communicate. Since the
link layer protocol adopted by POS terminals is SDLC, a timeout retransmission
mechanism is needed to handle communication exceptions during transmission of
data frames. To this end, you may set the packet interval timer. For a system that
must handle packets greater than 512 bytes, consider to increase the value of
packet interval.
POS network convergence ratios are usually quite high. To improve the utilization of
POS access ports, you need to limit the duration of each transaction, preventing a
POS terminal from occupying resources for a long time. To this end, you may set the
trade timer. If a transaction is not completed upon expiration of this timer, the router
disconnects the involved POS terminal to release the occupied resources.
Related Command: pos-server enable