What is the default port number for H.

The default port for H.323 signaling in IP Office is 1720 (Option B), per the H.323 standard, used for IP phones like the 1600 series. Option A (5060) is for SIP, Option C (8080) is for web services, and Option D (8443) is for Web Manager HTTPS.References: Avaya IP Office H.323 Configuration Guide.