VoIP Domain - SIP Proxy

What can I do here?

Use this window to create or edit a SIP Proxy (also known as a SIP server or Registrar).

Getting Here - Object Explorer > New > Network Object > More > VoIP Domain > SIP Proxy

VoIP Domains

There are five types of VoIP Domain objects:

• VoIP Domain SIP Proxy
• VoIP Domain H.323 Gatekeeper
• VoIP Domain H.323 Gateway
• VoIP Domain MGCP Call Agent
• VoIP Domain SCCP CallManager

In many VoIP networks, the control signals follow a different route through the network than the media. This is the case when the call is managed by a signal routing device. Signal routing is done in SIP by the Redirect Server, Registrar, and/or Proxy. In SIP, signal routing is done by the Gatekeeper and/or gateway.

Enforcing signal routing locations is an important aspect of VoIP security. It is possible to specify the endpoints that the signal routing device is allowed to manage. This set of locations is called a VoIP Domain. For more information refer to the R80 VoIP Administration Guide.

Supported SIP Deployments and NAT Support

The table shows a list of supported SIP deployments. NAT (Hide or Static) can be configured for:

• Phones on the internal network
• The proxy in the internal network

	No NAT	NAT for Internal Phones — Hide/Static NAT	NAT for Proxy — Static NAT
Endpoint to Endpoint	Yes	Static NAT only	Not applicable
SIP Proxy in External	Yes	Yes	Not applicable
SIP Proxy to Proxy	Yes	Yes	Yes
SIP Proxy in DMZ	Yes	Yes	Yes

The Proxy refers to a SIP proxy and/or registrar. If there is more than one proxy device, signaling passes through one or more Proxies or Registrars. After the call has been set up, the media passes from endpoint to endpoint, directly or through one or more Proxies.

SIP Endpoint-to-Endpoint Topology	The IP Phones communicate directly, without a Proxy. Static NAT can be configured for the phones on the internal side of the gateway.
SIP Proxy in External Network	The IP Phones use the services of a Proxy on the external side of the gateway. This topology enables using the services of a Proxy that is maintained by another organization. It is possible to configure Hide NAT (or Static NAT or no NAT) for the phones on the internal side of the gateway.
SIP Proxy to SIP Proxy	Each Proxy controls a separate endpoint domain. Static NAT can be configured for the internal Proxy. For the internal phones, Hide NAT (or Static NAT) can be configured.
SIP Proxy in DMZ	The same Proxy controls both endpoint domains. This topology makes it possible to provide Proxy services to other organizations. Static NAT (or no NAT) can be configured for the Proxy. Hide NAT (or Static or no NAT) can be configured for the phones on the internal side of the gateway.

Additional Conditions for Using NAT in SIP Networks

You can use SIP with Network Address Translation with these exceptions:

• NAT is not supported on IP addresses behind an external Check Point gateway interface.
• Manual NAT rules are only supported for proxy in DMZ deployments. (Use Automatic NAT as an alternative.)
• Calls cannot be made from an external source to two endpoints on the trusted side of a gateway if one of the endpoints is NATed and the other is not.