Paradyne BitStorm 2400, User Manual

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1. BitStorm 2400 Overview
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December 2002 2400-A2-GB20-10
Spectrum Manager
Spectrum Manager operates within the StormTracker EMS software and makes
EtherLoop spectrally compatible with asymmetrical services such as ADSL and
G.Lite, detecting and protecting against interference within the same binder. In
addition, EtherLoop in its native state is spectrally compatible with symmetrical
digital services such as T1, HDSL, HDSL2, or SDSL.
Although Spectrum Manager capabilities may seem like rate-limiting features, they
are simply spectral management functions. The primary benefit of spectral
management is that the lower upstream frequency (imposed by protect modes)
causes little or no interference with downstream frequency or other services in a
binder, thus reducing crosstalk.
Table 1-1, Spectrum Manager Modes , shows the various modes in which
Spectrum Manager operates.
Traffic Aggregation
The integrated Layer 2+ BitStorm 2400 IP DSLAM aggregates the traffic to and
from the gigabit Ethernet interfaces. It operates as a multi-port Layer 2+ Ethernet
bridge per the IEEE 802.1D/802.1Q specifications. The BitStorm 2400 IP DSLAM
and EtherLoop lines support the forwarding of IEEE 802.1Q tagged VLANs and
selective IP multicast forwarding (via IGMP Snooping).
Table 1-1. Spectrum Manager Modes
Mode Description
Native EtherLoop operates without the analysis of other service activity in the
individual loops.
Monitor Spectrum Manager analyzes other services in the loop that may limit
EtherLoop performance.
Forced EtherLoop provides optimum spectrally compatible performance with
asymmetric services in the individual loop that may temporarily affect
EtherLoop’s upstream capability. In this mode, EtherLoop is forced to
“mimic” asymmetric DSL.
Auto-Protect EtherLoop operates in an Asymmetric Mode if asymmetric interferers
are present. EtherLoop returns to normal upstream operations once
the interference is gone.
Video-Protect EtherLoop operates in a forced Asymmetric Mode with guaranteed
high downstream bandwidth for the delivery of streaming video
applications.