Integrator’s Reference Manual
6-70 80-99208-1 Rev. D
Protocol Stack Modific ation Commands
Caution
We strongly recommend that you d o not u se these comm ands i f you do
not have a thorough understanding of what they do and of how TCP
networking works.
TCP is used to ensure end-to-end integrity of data on the
over-the-air link in an async hronous data call. These
commands allow modification of the TCP st acks between the
modem and the Gateway IWF.
Caution
Improperly setting these commands can cause severe performance
degradation.

TCP Stack Changes ($QCTCP)

Syntax
$QCTCP[=<tcpmod>|[= <tcpmod>[,<lowertxm ss>[,
<uppertxmss>[,<rxms s>[,<minrto>[,<maxr to>[,<minato>[
,<maxato>[,<maxtcpb ackoff>]]]]]]]]]|?| =?]
Description
Allows you to modify the behavior of the TCP stack by
accessing to several variab les that control it. This includes
the ability to change the maximum segment size for both
transmit and receive, as well a s the ability to change the
values controlling the retransmit timer, and the
acknowledgment timer.
ERROR <mode> is not supported and Call
Mode is left unchanged.
$QCMODE:<mode>
OK
? is used to query current setting.
$QCMODE:(1-2)
OK
=? is used to query acceptable
range of the <mode> parameter.
Result Condition