Specifications

Network Requirements and Preparation
9 – 4 ShoreTel, Inc.
Voice Encoding
Voice encoding information is shown in Table 9-1.
Within a site, linear broadband encoding is recommended, since bandwidth in the local
area network is inexpensive and readily available. Between sites, G.729a is
recommended because it uses the least amount of bandwidth. The linear codec
provides slightly higher voice quality than G.711, but should not be used if there are
any bandwidth concerns.
If you select linear broadband or linear encoding, end points that do not support either
codec will negotiate for the highest quality codec for both end points, and G.711 is the
only high-quality codec shared by all end points.
NOTE ShoreGear-Teleworker and ShoreGear-12 (IPBX-12) do not support G.729 and
will use ADPCM for inter-site calls when the system is configured for G.729
encoding. Fax and modem calls should use G.711 voice encoding.
ShoreTel UDP Port Usage
ShoreTel 6.1 uses the following UDP ports for voice traffic.
Table 9-1 Voice Encoding
a
Linear Broadband Linear G.711 ADPCM G.729a
Sample rate 16 KHz 8 KHz 8 KHz 8 KHz 8 KHz
Effective sample
size
16 bits 16 bits 8 bits 4 bits 1 bit
Data rate 256 Kbs 128 Kbps 64 Kbps 32 Kbps 8 Kbps
Supported end
points
ShorePhone
IP110/210/212k/
530/560/560g
phones
All ShoreGear
ShorePhone
All ShoreGear
ShorePhone
IP110/210/
212k/530/560/
560g phones
All ShoreGear All except ShoreGear
Teleworker and ShoreGear-12
(IPBX)
ShorePhone IP110/210/212k/
530/560/560g phones
a. Activity Detection (VAD) / Silence Suppression is not supported.
UDP Port Description
111 Port mappers
2427 IP Phone MGCP destination source
2727 Switch MGCP destination
5004 RTP packet destination
5440 Location service protocol
5441 ShoreTel call control
5442 Call routing service
5443 Bandwidth manager in switch
5445 Admission control manager