Bandwidth Management - Nortel Passport 4400 Series Introduction Manual

Concepts and Applications

Bandwidth Management

The Passport 4400 utilizes ClearVoice, silence suppression and fax demodu-
lation technologies to reduce voice/fax bandwidth requirements as much as 96
percent, while delivering toll-quality voice. With both analog and digital voice/
fax offerings, the Passport 4400 delivers efficient integration networking on
WAN links ranging from 9.6 kbps to 1.544/2.048 Mbps.
Automatic fax demodulation
reduces fax bandwidth
requirements down to the fax
machine setting. For
example, a fax machine set
at 9.6 kbps requires only 9.6
kbps of bandwidth.
Synchronous (sync) data is
passed by sensing the
beginning and ending of sync
frames and sending only the
frame itself, not the idle
characters.
Dynamic Bandwidth
Allocation enables efficient
use of bandwidth.
PBX
Passport 4400
Bandwidth Management Technologies
Passport 4400 Introduction and Road Map
Voice is compressed from 64 kbps
(PCM) to toll-quality 8 kbps
ClearVoice. Silence Suppression
further reduces voice bandwidth
requirements.
Public Frame
Relay
Passport 4400
Frame Relay support allows
connections to public frame
relay services, which can
offer cost savings when
compared with private leased
lines.
Tunnel Switched Virtual
Circuits (SVC) reduce the
number of Permanent Virtual
Circuits (PVCs) purchased
from a carrier.
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