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Chapter 7
Automatic Performance Tests
Automatic tests are different to the measurements explained in previous chapters in
that they are usually easier to configure and run. Specifically, the user does not need
to worry about which bandwidth profile to use or which test payload to configure.
However, users are still required to enter the correct MAC and IP addresses, CoS
marks, and other frame and network configuration through the menu system (See
section 4.1.2 and See section 4.4.4). Due to the way automatic tests use the bandwidth
profile settings, the equipment may need to generate large amounts of traffic. This
traffic may cause congestion in some unprepared networks and damage performance
of any service already deployed. For this reason, users are advised to use automatic
measurements with care.
The second relevant property of automatic tests is that they provide a clear pass or fail
result that is easier to understand than a numeric latency figure or a bandwidth statistic.
Thresholds for the pass / fail results can be tuned through specific menus.
ALBEDO xGenius currently supports three different automatic measurements: The
IETF RFC 2544 test, the Ethernet service activation test methodology (eSAM) based
on the ITU-T Y.1564 standard and the IETF RFC 6349 TCP throughput test. The first
of them has been used for many years and its a very well established network
benchmarking mechanism. The second has been introduced more recently but it has
several advantages over the RFC 2544 tests like faster execution, support for multi-
service environments and support for colored traffic. Finally, the RFC 6349 is
specifically designed to TCP applications. TCP is connection oriented and it has its own
frame structure, handshaking, flow control and congestion management mechanisms
and for this reason testing TCP throughput is quite different to verification of non-
connection oriented protocols such as UDP.
In all automatic tests described in this chapter, Port A and Port B have always different
roles. Port A is always used for traffic generation and Port B is used only as an auxiliary
port. In two-way or asymmetric tests Port B has no role at all and the traffic runs
between Port A in the local unit and Port A in a unit installed in the remote end.bb
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