Specifications

Network Requirements and Preparation
Planning and Installation Guide 9 – 25
Note: Encryption is not supported on legacy ShoreTel switches or on the IP 100.
For instructions on enabling media encryption, refer to the section on Call Control
Options in the ShoreTel 6 Administration Guide.
Session Initiated Protocol (SIP)
There are no special network requirements necessary for deploying SIP. The general
system requirements should prove adequate for SIP support. With that in mind, please
note the following:
• SIP devices are supported behind NAT(Network Address Translation) as long as
they are configured statically.
• To communicate with a SIP device or service provider providing IP trunks over the
Internet, you must be able to pass SIP traffic through your firewall. This requires a
SIP application layer gateway – a feature typically provided by most firewall
vendors.
• SIP signaling uses UDP port 5060.
• When using SIP, the RTP port is dynamic and the SIP endpoints may not always
use the same ports to exchange information (in contrast with ShoreTel’s
proprietary protocol, which always uses port 5004). Thus, if you are using SIP, you
must deselect the “Always Use Port 5004 for RTP” check box on the Call Control
Options page in Director so that it is not fixed at 5004.