User Reference and Installation Guide
2-17
© 2006 Microwave Data Systems Inc.
All Rights Reserved.
MDS
Digital Radio
Series
05-4561A01, Rev. A
Figure 2-5. Ring Configuration.
SONET/SDH rings are inherently self-healing. Each ring has both an active path and a standby
path. Network traffic normally uses the active path. Should one section of the ring fail, the network
will switch to the standby path. Switchover occurs in seconds. There may be a brief delay in
service, but no loss of payload, thus maintaining high levels of network availability.
The consecutive point architecture implemented in the Digital Radio family is based on a point-to-
point-to-point topology that mimics fiber rings, with broadband wireless links replacing in-ground
fiber cable. A typical consecutive point network consists of a POP and several customer sites
connected using MDS Digital Radio Series units. These units are typically in a building in an
east/west configuration. Using east/west configurations, each unit installed at a customer site is
logically connected to two other units via an over-the-air radio frequency (RF) link to a unit at an
adjacent site.
Each consecutive point network typically starts and ends at a POP. A pattern of wireless links and
in-building connections is repeated at each site until all buildings in the network are connected in
a ring as shown in
166H 163H
Figure 2-6. . For 2 x 1+0 and 2 x 1+1 nodes payload and NMS connections
need to be jumpered between two SDIDU
TM
s. For 1 x 2+0 nodes, there is no need for jumpers as
there is a single SDIDU
TM
. For SDH or SONET payloads, the configuration is similar but an
external add/drop MUX and a second SDH/SONET interface card are required.
Summary of Contents for FOUR.9 Series
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