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Multiple EXNET® Rings

Overview

By installing multiple EXNET® rings, you can connect up to 4 nodes in a CSP system. Multiple EXNET® Rings shows a sample 4-node configuration of multiple EXNET® rings.

Figure 5-8 Multiple EXNET® Rings

Each node in Multiple EXNET® Rings has two EXNET-ONE cards installed, one for Ring 1 and one for Ring 2.

Nodes 1–3 transmit data on Ring 1, while Node 4 transmits data on Ring 2. Nodes 1–3 receive data from Node 4 on Ring 2, while Node 4 receives data from Nodes 1–3 on Ring 1. Nodes can transmit on multiple rings up to the ring capacity (number of nodes supported). You configure the Transmit/Receive Mode of each EXNET-ONE card by using the EXNET Ring Configure message.

Configuring the Transmit/Receive Mode of the nodes enables them to transmit on one ring and receive on all rings. As a result, each node can receive data from all other nodes. See the Developer’s Guide: Overview for information about configuring the Transmit/Receive Mode.

Limitations

The following limitations apply to multiple EXNET® rings:

• If conferencing is configured, you cannot have more than 8 CSP nodes.

Redundancy

For full redundancy with multiple rings, configure your system as follows:

1. Add two EXNET-ONE cards to each node for a total of four card sets per node.

2. Connect cables as explained in Connecting the Fiber Optic Cable above.

3. Configure the Transmit/Receive Mode of each node.

Redundant Multiple EXNET® Rings shows a node configured for two redundant EXNET® rings.

Figure 5-9 Redundant Multiple EXNET® Rings

Excel's open architecture, proprietary, 1.3 Gbps fiber optic network using a packet-based protocol.