Forefront TMG H.323 Filter Test

The Forefront TMG includes a H.323 protocol filter which allows multimedia enriched applications like Microsoft Windows NetMeeting to place calls through the H.323Gatekeeper filter. NetMeeting allows you to video conference using an electronic white board, exchange files, text chat and have voice conversations with two or more parties. If the firewall is H.323 compliant then you will be able to place these calls through it. Most new video conference systems comply with this standard and have had huge success over Microsoft networks. H.323 protocol filter does not directly allow clients to communicate directly with their peers and acts as a true proxy. This method protects the integrity of your network making it more secure and avoiding personal attacks on unsuspecting users.

The Forefront TMG H.323 Filter test helps the administrator to track the number of currently active H.323 calls and the total number of H.323 calls handled since the start of the firewall service.

Target of the test : A Forefront TMG Server

Agent deploying the test : An internal agent

Outputs of the test : One set of results for the Forefront TMG that is to be monitored.

Configurable parameters for the test
Parameter Description

Test Period

How often should the test be executed.


The IP address of the host for which this test is to be configured.


The port at which the specified host listens to. By default, this is 1745.


If this parameter is set to Yes, then it means that, by default, all the Forefront TMG servers being monitored by the eG system are the passive servers of a Forefront TMG cluster. No alerts will be generated if the servers are not running. Measures will be reported as “Not applicable” by the agent if the servers are not up.

Measurements made by the test
Measurement Description Measurement Unit Interpretation

Active calls

Indicates the number of H.323 calls that are currently active.



Total calls

Indicates the total number of H.323 calls handled by the H.323 filter since the start of the firewall service.