To fully use Merge services a client SIP user agent needs access to following ports used by the Merge Service Platform:
| Port range | Protocol | Description | Application |
| 5060 | UDP | SIP signaling | SIP Proxy/Registrar/Presence Agent |
| 53 | UDP | DNS resolution | DNS and ENUM |
| 50000:60000 | UDP | RTP media | MediaProxy – RTP media relay |
| 2855 | TLS | MSRP media | MSRP relay – MSRP media relay |
| 443 | TLS | XCAP storage | OpenXCAP – Presence policy management |
Having some of these ports blocked is one of the main reasons for having trouble with Merge services. Check for your network administrator to check your settings.
