Archive for the ‘Cisco Unity Express’ Category

One of the current limitations is that the JTAPI (CTI-quick buffer encoding [QBE]) signaling packets are unmarked (TOS = 0) when the Cisco Unity Express AIM transmits them. In order to correct this, use an access control list (ACL) on the router that has the Cisco Unity Express AIM installed to mark and prioritize the traffic.

The JTAPI signaling from the Cisco CallManager is correctly marked with a differentiated services code point (DSCP) value of CS3.

The JTAPI signaling protocol uses TCP port 2748. Dedicate 20 kbps per Cisco Unity Express site for this traffic.

All Real-Time Protocol (RTP) audio traffic from the Cisco Unity Express AIM or the IP phone is correctly marked with a DSCP value of 0xEF.

This example shows a sample configuration for this on the router where a.b.c.d is the IP address of the Cisco Unity Express AIM:

access-list 101 permit tcp host a.b.c.d any eq 2748
class-map match-all cti-qbe
 match access-group 101
policy-map cti-qbe
 class cti-qbe
 set dscp af31
 bandwidth 20
interface Serial0/1
 service-policy output cti-qbe