Routing Principles in SIP Cluster

[In progress] The following sample deployment diagram illustrates the routing principles in SIP Cluster:

In the above diagram, there are two data centers (DC1 and DC2) with two SIP Cluster Nodes each. All SIP Cluster Nodes share the same switch (SIP Cluster Switch) where all Routing Point DNs and agent DNs are configured. Each SIP Cluster Node has a dedicated routing solution consisting of URS, ORS, and Stat Server. The same strategy is loaded on all SIP Cluster Nodes to enable distribution of inbound calls across the nodes and process the calls according to the strategy.

To offload a Virtual Queue (VQ) DNs traffic that might be generated in complex large contact center deployments, the SIP Cluster architecture includes a switch (VQ Switch) dedicated to VQ DNs. A single HA pair of SIP Server instances running in non-cluster mode is assigned to that VQ Switch in each data center. SIP Server instances serving the VQ Switch are also used for agent reservation.

ORS Deployment

• A dedicated one-node ORS Cluster is deployed to serve each SIP Cluster node.
• A dedicated Cassandra ring is deployed for each ORS Cluster.
  • cassandra-keyspace-name: Orchestration
  • cassandra-nodes: FQDN_SIP_Cluster_Primary_VM; FQDN_SIP_Cluster_Backup_VM

Important

To create a high performance solution, the number of ORS pairs per SIP cluster node can be increased.

VQ Switch Configuration and Connectivity

VQ switches offer a distributed agent reservation solution for a blended environment (voice and multi-media). A VQ switch is a centralized place for VQ DN configuration and they help simplify provisioning. VQ switches also result in a performance improvement by helping unload VQ traffic from the SIP cluster.

In the above sample diagram, there is one VQ SIP Server pair per DC. Having independent SIP Server pairs configured with the same switch is possible because we are not provisioning any real DNs on this switch. As a result, the SIP Server pair do not interfere with each other.

• One HA VQ SIP Server is deployed per DC.
• All VQ SIP Servers are assigned to the same VQ switch. Only VQ DNs are configured in the VQ switch.
• The routing Stat Server instance is connected to all VQ SIP Severs, but each URS and ORS instance is connected only to the VQ SIP Server located to in the local DC.

For more information, refer to Configuring Switch and DN Objects for SIP Cluster.