[ippm] Testing TCP Throughput Capacity in Operator Networks

Hello,

I work in the communications test industry and we have seen a growing need to verify the capacity of a network in terms of end-end TCP throughput.

Most network operators use RFC-2544 based Layer 3 tests to verify the SLA of the network, but this has significant shortcomings since it does not verify the ability of the network to carry a customer’s TCP traffic. Ideally, a TCP layer throughput test would detect issues with prioritization, queuing, policing, etc. This type of test could also detect issues such as TCP Tail drop phenomena in the network.

I have spoken to several network operators and equipment providers and there is a consistent desire to test throughput at the stateful TCP layer, at line rate speeds (1G-10G), and to conduct these tests in a standardized manner.

At a very high level, a standardized TCP layer throughput test would:

- Run a latency test and automatically compute the ideal TCP window size for the test network

- Conduct a series of single and multiple connection TCP tests and vary the window size to verify throughput per window size

- Conduct QoS testing, tagging the TCP connections with appropriate prioritization (DSCP, etc.) and test in the midst of background traffic loads

This is a very simplified description of the test workflow.

I would like to solicit the interest of members within the IPPM workgroup and would like to move forward with a draft document to describe this test in detail.

Thank you,

Barry

Principal Member of Technical Staff

JDSU Communication Test (formerly Acterna)

Emerging Markets and Technology Research

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