User's Manual
Integrators’ Reference Manual for ViewStation EX, ViewStation FX, and VS4000
64 www.polycom.com
The PRI T1 needs to be provisioned for the ViewStation FX and 
VS4000 systems as follows: 
Table 3-4. ISDN PRI Requirements
Line settings ESF/B8ZS (default)
Extended Super Frame B8ZS is modem standard for 
T1/PRI line encoding and framing
Line termination 
type
CPE (user side) only
The required termination is built into the system and 
most access switches
Supported PRI 
switch protocols
AT&T 4ESS, AT&T 5ESS, NI-1, NI-2, Siemens, 
Nortel DMS 100, and Nortel 250
These are standard protocols for North America
Number of 
channels
23 B-channels dialable at 64 or 56 Kbps, and one D 
channel
Ensure that you have 64 Kbps clear channel service
Number of 
network 
interfaces
1 (single PRI)
Line build-out 
modes
DSU+CSU (0 to –22.5dB attenuation), DSU-only 
(DSX 0-665 feet)
Physical distance is offset by the settings in the user 
interface 
Clocking Must be derived from the external network or the 
PBX
Terminal 
Endpoint ID 
(TEI)
0-63
This identifies the PRI endpoint; the common default 
is 0
Numbering One local directory number per interface (23 
channels)
D-channel slot 
number
24
Included to verify where the D channel is; this is 
where additional diagnostic information resides
Call-by-call 
service codes
Values 0-31 service codes for GVPN/PN/UPN 
network-specific services










