Step load CIR test

../../_images/eth-cir.png

This task verifies that an Ethernet service QoS profile behaves as expected as the bit rate is increased. It is assumed that the service has a QoS profile with the CIR parameter as well as the maximum frame loss ratio, delay, and jitter values for conforming frames. For the generated flow the following parameters need to be specified: frame size, load frame size, the source and destination UDP port, DSCP value, and VLAN priority (p-bits).

Reference

The test performed conforms to ► ITU-T Y.1564 section 8.1.2, test A.2 (“CIR configuration test: Step load CIR test”).

Test procedure

  • The sender Test Agent starts by generating frames at a rate of 0.25 × CIR.

  • The receiver Test Agent measures received rate, loss, delay, and jitter on the flow. If the last three metrics are below the maximum frame thresholds, the test is repeated at a higher rate. In each step, the rate is increased by the Load step size parameter. This procedure is iterated until CIR is reached.

Fail criteria

  • The test fails if any of the thresholds Max frame loss, Max frame delay, or Max frame jitter is exceeded in any step.

Parameters

General

  • Sender: The sender Test Agent interface.

  • Receiver: The receiver Test Agent interface.

  • Load step size (Mbit/s): The amount by which the rate is increased in each step. No default.

  • Test duration (s): Duration of the test in seconds. Min: 5 s. Max: 60 s. Default: 20 s.

  • Wait for ready: Time to wait before starting this test step. The purpose of inserting a wait is to allow all Test Agents time to come online and acquire good time sync. Min: 1 min. Max: 24 hours. Default: “Don’t wait”, i.e. zero wait time.

QoS profile

  • CIR (Mbit/s): Committed Information Rate. Min: 0.1 Mbit/s. Max: 10,000 Mbit/s. No default.

  • Max frame loss (%): Maximum frame loss ratio for conforming packets. Min: 0%. Max: 100%. No default.

  • Max frame delay (ms): Maximum frame delay for conforming packets. Min: 0 ms. Max: 1000 ms. No default.

  • Max frame jitter (ms): Maximum frame jitter for conforming packets. Min: 0 ms. Max: 1000 ms. No default.

Traffic profile

  • Frame size (bytes): Ethernet frame size in bytes. Min: 64 bytes. Max: 1514 bytes. Default: 512 bytes.

  • Source UDP port: The source UDP port to use. Range: 1 … 65535. Default: 5000.

  • Destination UDP port: The destination UDP port to use. Range: 1 … 65535. Default: 5000.

  • DSCP: Differentiated Services Code Point. Min: 0. Max: 63. Default: 0.

  • VLAN priority (PCP): Priority Code Point in VLAN header. Min: 0. Max: 7. Default: 0.

Result metrics

  • Rate (Mbit/s): Ethernet data rate.

  • Loss (%): Packet loss.

  • Delay (ms): Average one-way delay.

  • Jitter (ms): Jitter (delay variation).

  • Pass/fail outcome of test.