Lucent Technologies DDM-2000 OC-3, User & Service Manual

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363-206-285
Applications
2-66 Issue 3 June 2001
DS1 Performance Monitoring for Tariff Verification 2
It is critical in the growing, high-reliability DS1 services market that DS1
performance be accurately measured and recorded in order to verify the terms of
a DS1 tariff. The DDM-2000 OC-3 Multiplexer's DS1 PM capability allows a
service provider to access this lucrative market by gathering and maintaining DS1
path performance data. The service provider can then use this data to confidently
verify the terms of a DS1 tariff.
Figure 2-45 demonstrates a typical configuration for DDM-2000 OC-3 Multiplexers
configured to provide DS1 PM. In this example, a business customer is using
DS1s to interconnect a LAN at their remote office with an LAN at their corporate
headquarters. The DS1 circuit is provided by a public carrier. Starting at the
corporate headquarters (location A), an extended superframe (ESF) formatted
DS1 is fed into the DDM-Plus or DDM-2000 FiberReach and DDM-2000 OC-3
equipment, carried across the public network, and delivered to the LAN bridge/
router at the company's remote office (location Z). There the LAN bridge/router
(owned by the business customer) evaluates the number of bit errors occurring in
the trip from headquarters to the remote office and sends a message in the
opposite direction of the ESF data link, reporting these error statistics. The
DDM-2000 OC-3 Multiplexer receives this message and stores the information
locally on its DS1PM circuit pack. The DDM-2000 OC-3 Multiplexer does this
continuously, gradually building a repository of DS1 performance data on the link
from location A to location Z. This information is always available to the public
carrier's operations center by querying the DDM-2000 OC-3 Multiplexer via its CIT
or TL1 links. Similarly, the DDM-2000 OC-3 Multiplexer at the company
headquarters maintains all the performance data on the link from location Z to A
and this data is also transmitted over the TL1 interface. Taken together, these two
sources of data provide verification of the 2-way DS1 link between location A
and Z.
Beginning with Releases 11.1 and 13.0, a DS3 Transmultiplexer (TMUX) circuit
pack is available for installation in the function unit slots of the DDM-2000 OC-3
shelf. The TMUX accepts an M13 or C-bit formatted DS3 signal and demultiplexes
it into 28 DS1s. Performance monitoring can then be done at the DS3 and DS1
(measuring the same path parameters as the DS1 PM circuit pack) levels . This
new circuit pack eliminates the need for a separate M13 multiplexer and can add
versatility to your tariff verification capabilities (TMUX not shown in Figure 2-45).
See Figure 2-46 for a DS3 Transmultiplexer application.