What is WebLogic SIP Server and its architecture
WebLogic SIP Server is designed to provide a highly scalable, highly available, performant server for deploying SIP applications. WebLogic SIP Server is a multi-threaded application server that carefully manages resource allocation, concurrency, and thread synchronization for the modules it hosts. To obtain the greatest advantage from the WebLogic SIP Server architecture, construct your application modules according to the SIP Servlet and J2EE API specifications.
The WebLogic SIP Server architecture is simple to manage and easily adaptable to make use of available hardware. The basic architecture consists of these components:
A load balancer (or multiple load balancers) is an essential component of any production WebLogic SIP Server installation. The primary goal of a load balancer is to provide a single public address that distributes incoming SIP requests to available servers in the WebLogic SIP Server engine tier.
In a WebLogic SIP Server installation, the load balancer is also essential for performing maintenance activities such as upgrading individual servers (WebLogic SIP Server software or hardware) or upgrading applications without disrupting existing SIP clients. The Administrator modifies load balancer policies to move client traffic off of one or more servers, and then performs the required upgrades on the unused server instances.
Most load balancers have configurable policies to ensure that client requests are distributed according to the capacity and availability of individual machines, or according to any other load policies required by your installation.
The engine tier is a cluster of WebLogic SIP Server instances that hosts the SIP Servlets and other applications that provide features to SIP clients. The engine tier is a stateless cluster of servers, and it stores no permanent or transient information about the state of SIP dialogs. The primary goal of the engine tier is to provide maximum throughput and low response time to SIP clients. SIP Servlets are deployed uniformly to all server instances (by targeting the cluster itself) and the load balancer need not maintain an affinity between SIP clients and servers in the engine tier.
The data tier is a cluster of WebLogic SIP Server instances that provides a high-performance, highly-available, in-memory database for storing and retrieving the session state data for SIP Servlets. provide reliable, performant storage for session data required by SIP applications in the WebLogic SIP Server engine tier. To enable administrators to easily scale hardware and software resources as necessary to accommodate the session state for all concurrent calls.