TULIP - Free protocol Simulator

Tulip generally permits a great freedom in defining messages to be sent towards the tested system. This brings an even greater difficulty to correct the following errors:

- Syntax errors/formatting erros when sending packets or matching incoming ones (for example, missing carriage return).

- Real-time problems (reception of a message not expected yet, or reception timeout too low).

Two tools are used to correct the majority of these errors:

1) Test mode

The test mode allows validating a test scenario without using the actual test network. To do so, the distant element is simulated by a test traffic agent (AGENT_TEST in the configuration file).

Le transport protocol is replaced by an internal loop:

- Packets sent by normal traffic agents are routed towards test traffic agents.

- Packets sent by test traffic agents are routed towards normal traffic agents.

The responder can be used in this mode, as well as a test responder. The command used to start a test responder is <START_TEST_RESPONDER>.

In order to activate test mode:

- Configuration file: the TEST anchor has to be enclosed within anchor <ENVIRONMENT>. The <AGENTS> anchor shall include some <AGENT_TEST> declarations.

- Test scenario: test traffic agents are launched using SPAWN_AGENT command like normal traffic agents. To send/receive packets from a normal traffic agent, the commands SEND/EXPECTED are used, while to send/receive packets from a test traffic agents, commands TEST_SEND/TEST_RECEIVE are used instead.

2) Debug mode

During scenario troubleshooting, it is useful to activate some debug traces, to check the commands are executed as planned. To do this, the <DEBUG> anchor in the configuration allows to modify the default log level with the LEVEL attribute (1 to 4). Generally, level 1 is sufficient for user level scenario troubleshooting.

Debug entries use application standard output, or can be redirected towards a file (-to command-line option).

Corresponding entries are recognized thanks to DEBUG prefix, like for instance:

DEBUG 22:30:55 : CPipelineNetwork::Open_stream