MRV Communications LambdaDriver 400, User Manual

Page: 172 / 207

LambdaDriver 400 & 800
ML46430, Rev. 07
October 2004
Appendix C:
LoopBack Tests
Table 23
General
LoopBack tests (RLB, LLB, and TLB tests) are used to identify the faulty element of a network.
Transponders
This section describes the loopback tests for an LDx00 network using Transponders for
connecting access units.
Hardware/Software Control
shows, for each transponder model, whether RLB and LLB tests can be software or
hardware controlled.
Table 23: Transponder RLB and LLB Control by Software and Hardware
RLB LLB Transponder
Model
S/W H/W S/W H/W
TM-SFP
9 9 9
TM2-SFP 9 9
TM-DXFP
9 9 9 9
RLB Test
Purpose
The RLB test is used to determine whether the local LDx00, WDM cabling connected to it, and
remote LDx00’s WDM interface are OK.
Data Path
The data path (roundtrip) in an RLB test is shown schematically in F below. igure 80
Figure 80: Data Path in RLB Test using a Transponder
The data path in detail with reference to F is as follows: igure 81
Local LDx00 (Transponder Æ Mgt Æ OA Æ OADM or Mux Æ 1+1 or Service) Æ
WDM Trunk Cabling Æ
Remote LDx00 (1+1 or Service Æ OADM or Demux Æ OA Æ Mgt Æ Transponder,
excluding interface to Access Unit Æ Mgt Æ OA Æ OADM or Mux Æ 1+1 or Service) Æ
172