Local Customer Transparent Loopback

network side.

Local CustomerNTUTransparentTxDataLoopbackLTU – Provides a loopback at the NTU in the customer direction (Figure 14). Data is passed transparently to the

Figure 14. Local Customer Transparent

Loopback

Remote CustomerNTUTransparent Loopback –

Initiated at the and provides a loopback at the LTU in the customer direction (Figure 15). Data is passed transparently to theTxDatane work LTUside.

Figure 15. Remote Customer Transparent

Loopback

Local CustomerNTUNontransparentTxAIS LTUoopback – Provides a loopback at the NTU in the customer direction (Figure 16). AIS signal is injected into the

Figure 16. Local Customer Nontransparent

Loopback

Remote CustomerNTUNontransparentLTULoopback –

Initiated at the and provides a loopback at the LTU in the customer direction (Figure 17). AIS signal is injected into theTxnetworkAIS side.

Figure 17. Remote Customer Nontransparent

Loopback

Local Network Transparent Loopback – Provides a
loopback at the	U in the network direction (Figure
18). TxDataDatais passedNTUtransparently to theLTUcustomer side.

Figure 18. Local Network Transparent

Loopback

Remote NetworkNTUTransparent LoopbackLTU Tx–DataInitiated at the NTU and provides a loopback at the LTU in the network direction (Figure 19). Data is passed transparently to the customer side.

Figure 19. Remote Network Transparent

Loopback

Local Network NTUontransparent LoopbackLTU – Provides a loopback at the NTU in the network direction (Figure 20). AIS signal is injected into the customerTxAISside.

Figure 20. Local Network Nontransparent

Loopback

Local NetworkNTUNontransparent LTUoopbackTxAIS– Initiated at the NTU and provides a loopback at the

LTU in the network direction (Figure 21). signal is injected into the customer side.

Figure 21. Remote Network Nontransparent

Loopback

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