Cisco Cisco IOS Software Release 12.4(4)T

 lists the feature release history for this feature.

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 lists only the Cisco IOS software release that introduced support for a given feature in a given 

Cisco IOS software release train. Unless noted otherwise, subsequent releases of that Cisco IOS 
software release train also support that feature.

IP SLAs RTP-Based VoIP Operation

12.4(4)T

The Cisco IOS IP Service Level Agreements (SLAs) 
Internet Control Message Protocol (ICMP) jitter operation 
provides the capability to generate a stream of ICMP 
packets to gather network performance-related statistics. 
Available statistical measurements for the IP SLAs ICMP 
jitter operation include latency, round-trip time, jitter 
(interpacket delay variance), and packet loss between a 
Cisco device (source) and any other IP device (destination).

IP SLAs RTP-Based VoIP Operation 
Enhancements

12.4(6)T

New statistical measurement options for the 
source-to-destination data path were added.