Synchronous Ethernet network configurations

Overview

Synchronous Ethernet provides the Alcatel-Lucent 1850 TSS-5 the capability to derive timing based on incoming data from the packet network.

This section describes the following examples of synchronous Ethernet network configurations:

• VLNC60/64 synchronous Ethernet network configuration

• VLNC42/42B/60/64 synchronous Ethernet network configuration

• VLNC42/42B/52/55 synchronous Ethernet network configuration

VLNC60/64 synchronous Ethernet network configuration

In this configuration the hub VLNC64 circuit pack recovers timing from the SONET/SDH line (OC-3/OC-12) or from a BITS source. The remote VLNC60 circuit pack recovers timing from the incoming GE port.

The VLNC60 circuit pack may also be used with the VLNCN40/42/42B circuit pack in a wireless base station to backhaul Ethernet and circuit emulation traffic.

VLNC42/42B/60/64 synchronous Ethernet network configuration

In this configuration, the VLNC64 circuit pack recovers timing from the SONET/SDH line (OC-3/OC-12) or from a BITS source. The remote VLNC42/42B circuit pack recovers timing from an incoming GE port and provides timing to a collocated VLNC60 circuit pack using the backplane 25 MHz signal. The VLNC6x and VLNC42/42B circuit packs may provide timing to collocated circuit packs using the backplane 25 MHz signal.

VLNC42/42B/55 synchronous Ethernet network configuration

In this configuration, the VLNC55 circuit pack recovers timing from the SONET/SDH line (OC-3/STM-1, OC-12/STM-4, OC-48/STM-16). The collocated VLNC42/42B circuit pack recovers timing from the incoming GE port or the backplane 25 MHz signal.

VLNC42/42B/55 synchronous Ethernet - backplane mode

In Release 7.2.2, the VLNC55 timing mode can be provisioned as backplane. The clock is recovered from the synchronous Ethernet inputs on the collocated VLNC42/42B, sent across the 25 MHz backplane connections to the VLNC55 and into the timing generator. Ethernet SSMs are sent across the GbE backplane connection to the VLNC55 and used for system timing. The clock is used to time OCn/STMn outputs, and they are sent back over the backplane to the VLNC42B and used to time the synchronous Ethernet outputs on the VLNC42/42B.