Single- and dual-homing

Overview

End users are demanding service with high availability. Service providers are responding with tariffs that rely on self-healing networks to offer high availability service. Some of these tariffs even call for penalties for the service provider when service is interrupted or has a high error rate. The Alcatel-Lucent SONET product family offers many options for meeting Alcatel-Lucent 1665 DMX service needs. One of these, OC-3/12/48 ring transport on Alcatel-Lucent 1665 DMX ring networks, can be implemented in single- and dual-homing configurations.

For lower-density TDM applications, Alcatel-Lucent 1665 DMX can provide an OC-3/12/48 optical ring termination for a DDM-2000 OC-3 Multiplexer, DDM-2000 OC-12 Multiplexer, DDM-2000 FiberReach, or any other compliant network element. This feeder ring is useful for evolving lower-density access transport applications into high-rate access networks.

Description

The figure below shows a dual-homed OC-3 extension from two remote nodes on an Alcatel-Lucent 1665 DMX access ring. OC-3 extensions from Alcatel-Lucent 1665 DMX rings are available when the Alcatel-Lucent 1665 DMX Function Unit groups are equipped with OC-3 OLIU circuit packs. OC-12/48 extensions from Alcatel-Lucent 1665 DMX rings are also available. The host nodes must be Alcatel-Lucent 1665 DMX NEs. For an example of single homing, see the following page.

Figure 3-34: Dual homing example

The figure below provides an example of both single and dual-homing. Path protection switching is employed for dual-homed and single-homed applications in the same manner. That is, 50 millisecond path switching is supplied by the remote DDM-2000 OC-3/OC-12/FiberReach nodes and the Alcatel-Lucent 1665 DMX systems. The Alcatel-Lucent 1665 DMX host node dual homing configuration differs from that used for single-homing because each host node transports only one leg of the OC-3/OC-12/OC-48 extension. At each host node, a connection is made from the single OC-3/OC-12/OC-48 extension to just one rotation of the Alcatel-Lucent 1665 DMX host ring. Dual- and single-homed extensions can also be mixed at a host node, allowing the access network to be tailored efficiently to different groups of customers. Host nodes could also be Alcatel-Lucent 1665 DMXtend.

Figure 3-35: Multi-node OC-3/OC-12 ring with OC-48 ring transport

Configuration advantage

Alcatel-Lucent 1665 DMX provides a seamless transmission and operations integration with lower-capacity ring networks, as well as increased scalability for those established networks. So, single and dual-homing provide additional topological flexibility in UPSR configurations supporting voice and data services.