The 7705 SAR supports the test heads, as defined in RFC 2544, for ITU-T Y.1564. Test heads allow users to configure a set of trusted procedures to use during testing.
An ITU-T Y.1564 test head cannot survive activity switches (on platforms supporting HA), or any maintenance operation at the port, SAP, service level. The user must restart the test from the newly active CSM. If an activity switch occurs during an active test, all statistics and measurement data are lost.
An Ethernet SAP loopback can survive a CSM activity switch if it is enabled with the persistent keyword. Otherwise, the loopback is also reset during an activity switch. Ethernet SAP loopbacks are supported on LAG and MC-LAG ports on second-generation and third-generation Ethernet cards.
ITU-T Y.1564 test heads rely on delay and delay variation when calculating jitter. For more details, see RFC 3550, section A.8.
Users can configure the following frame type using the frame-payload command: Layer 2 payload, IPv4 payload, and IP/TCP/UDP payload. The test head uses the configured values for the IP header fields and TCP header fields based on the payload type configured.
The test head implementation on the 7705 SAR allows users to run tests with up to four parallel flows by specifying up to four frame payload IDs in the oam>testhead command. This allows users to test a service with IMIX-type traffic patterns.