Multipoint Downspeeding; Table 6-2.Mixed Protocol Dialing Speeds - Polycom ViewStation FX4000 User Manual

Multipoint Downspeeding

© Polycom, Inc. 2002
Table 6-2. Mixed Protocol Dialing Speeds
Number of
Network Endpoints and
Interface Type of Calls
PRI with Mixed With any
Protocols (ISDN combination of
and IP) ISDN and IP calls:
2
2
3
4
BRI with Mixed 2 lines with:
Protocols (ISDN
1 ISDN + 1 IP
and IP)
2 ISDN + 1 IP
2 IP + 1 ISDN
3 lines with:
1 ISDN + 1 IP
2 ISDN + 1 IP
2 IP + 1 ISDN
4 lines with:
1 ISDN + 1 IP
2 ISDN + 1 IP
2 IP + 1 ISDN
When necessary, the ViewStation FX or VS4000 is able to downspeed
calls, meaning that it can dynamically reduce the data rate of the call
to accommodate incoming calls. For example, if there is an existing
point-to-point conference at 384 Kbps and an endpoint calls into the
conference at 128 Kbps, the conference systems will downspeed the
384 Kbps call to 128 Kbps so that all the sites are connected at 128
Kbps. Conversely, incoming IP and ISDN calls dialed at speeds
greater than the current conference speed are negotiated down to
Chapter 6 - Using Advanced System Features
Maximum Speed For Each
Party in the Call
(in Kbps)
ISDN(H.320)
1472 (T1)
1920 (E1)
512
384
256
128
256
384
192
384
512
256
384
IP (H.323)
1920
1920
512
384
256
128
256
384
192
384
512
256
384
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