Service Assurance Agent

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Please improve this article if you can. (September 2006)

Service Assurance Agent (SAA) is an active measurement technology initially developed by Cisco. SAA is sometimes also referred to in conversation as Application Performance Monitor (APM) or Response Time Responder (RTR).

Note: This technology was previously known as the Response Time Reporter (RTR), then as the Service Assurance Agent (SAA) and has since been renamed to IP SLAs.

[edit] What SAA does

With SAA, routers and/or switches perform periodic measurements. These include:

HTTP Get
FTP downloads
DNS lookups
UDP Echo (for VoIP Jitter & MOS)
DLSw (SNA Tunneling protocol)
DHCP lease requests
TCP Connect
ICMP Echo (remote ping)

The exact number and type of available measurements depends on the IOS version. SAA enables building truly distributed performance collection systems. SAA is very widely used in service provider networks to generate time-based performance data. It is typically used together with SNMP and Netflow which generate volume-based data. SAA is often used to generate data which is need by IP SLAs.

[edit] Important things to know

For SAA measurements needs a device with SAA support. SAA is supported on Cisco routers and switches since IOS version 12.1. Other vendors like Juniper or Enterasys support SAA on some of their devices.
SAA measurements and data collection can be configured via the console (command line) or via SNMP.
When using SNMP, both read and write community strings are needed.
The SAA voice quality feature was added starting with IOS version 12.3(4)T. All versions after this including 12.4 mainline contain the MOS and ICPIF voice quality calculation for the SAA UDP jitter measurement.