2 Overview

As service providers deploy larger and larger SIP access networks, scalability problems are presenting unique challenges, particularly from an operational standpoint. Deployments that scale beyond the number of users serviceable by a single Oracle Communications Session Border Controller (OCSBC) – as well as deployments that use a geographically redundant OCSBC for catastrophic fail over purposes – encounter edge reachability problems. In general there are two coarse techniques that carriers use today to support end-point populations that exceed one Oracle Communications Session Border Controlled capacity: they either use a DNS-based distribution mechanism, or they will pre-provision endpoint to point to specific OCSBCs (manually load balancing them). Each of these solutions has its drawbacks. End users – many of them familiar with load balancing equipment deployed to scale protocols such as HTTP or SMTP – have expressed interest in a device that will perform dedicated load balancing for their SIP endpoint.

The SLB addresses the need for scaling a network edge to millions of endpoint. Designed as a standalone system, the network architect can deploy a physical or virtual SLB capable of supporting an extremely large number of endpoints, where an endpoint is defined as a unique source and destination IP address. The SLB aggregates signaling from large endpoint populations to reduce the edge reachability problems.

The network architect reduces this problem by deploying clusters of OCSBCs supported by the SLB. These OCSBCs can be operating as either Physical Network Functions (PNFs) and Virtual Network Functions (VNFs). The SLB supports clusters of homogenous or heterogenous groups of PNFs and/or VNFs.