Specifications

7-74

Reference Guide

Model No.

Running Head

PARS Screen WAN Card

7.5.8 Line Protection - Link Failure

When WAN links fail, the ring will break. The integrated access device will stop delivering

traffic to the broken links and will reroute the traffic through the ring and loop them before the

broken lines.

Figure 7-51. PARS Normal Operation Mode (two nodes)

Figure 7-51 shows details of PARS mode for two nodes. Primary WANs are cross-connected

to secondary. User cards appear to be terminated normally on the primary WAN. They are

actually split between RX of the primary and TX of the secondary, as shown. Note that the

physical connections between nodes are shown from the secondary WAN of one node to the

primary WAN of the adjacent node.

W2-2

W2-1W1-1

W1-2

HSU, FXS, FXO, E&M or SRU

1 2 3 4

HSU, FXS, FXO

E&M or SRU

1 2 3 4