ITU-T Recommendations

Recommendation ITU-T H.460.18 extends Recommendation ITU-T H.323 to enable ITU T H.323 devices to successfully exchange signalling and establish calls, even when they are placed inside a private network behind NAT/FW devices. These extensions, when used together with the facilities of ITU T H.460.19, enable ITU-T H.323 endpoints to traverse NAT/FW installations with no additional equipment on the customer premises. Alternatively, the ITU-T H.460.18 extensions may be implemented by a proxy server to support unmodified ITU-T H.323 endpoints.
This revision introduces a number of corrections and clarifications by incorporating technical and editorial corrections from the ITU-T H.323-series Implementers Guide (03/2011).