Does an endpoint have to use a gatekeeper? (Q83)
The information in this article applies to:
Technically, no, but most feel that the intent of H.323 is for an endpoint to use a gatekeeper.
In support of the argument that a gatekeeper is required, this passage if often cited (Section 7.2.2/H.323v4): "As part of their configuration process, all endpoints shall register with the Gatekeeper identified through the discovery process. Registration shall occur before any calls are attempted and may occur periodically as necessary..." (Our emphasis.) However, H.323 does not require an endpoint to perform gatekeeper discovery, either manually or automatically, and H.225.0 clearly states that "an endpoint may discover/register with a Gatekeeper." Therefore, if an endpoint does not "discover" a gatekeeper, it does not have a gatekeeper with which to register, and the first passage does not apply.
Moreover, consider the following passages that bolster the argument that H.323 does not require a gatekeeper:
- Section 6.4/H.323v4: "The Gatekeeper, which is optional in an H.323 system,..."
- ibid: "When it is present in a system, the Gatekeeper shall provide the following services:..."
- Section 7.1.3/H.323v4: "When there is no Gatekeeper in the system,..."
- Section 7.2.2/H.323v4: "An endpoint which is not registered with a Gatekeeper is called an unregistered endpoint. This type of endpoint does not request admission permission from a Gatekeeper and so cannot participate in admissions control, bandwidth control, address translation and other functions performed by the Gatekeeper."
- Section 8.1.1/H.323v4: "In the scenario shown in Figure 29 neither endpoint is registered to a Gatekeeper. The two endpoints communicate directly."
- Section 8.1.12/H.323v4: "If a Gatekeeper is present,..."
- Section 6.1/H.225.0v4: "Before any calls are made, an endpoint may discover/register with a gatekeeper. If this is the case,..."