What is Java Application Server & IBM WebSphere application server?

Application Server provides the entire necessary infrastructure to host enterprise application. It handles application operation between user request to backend business application like a database, messaging, etc.

Enterprise application, which is usually transactional based or heavily used, must have an application server with built-in redundancy, high availability, and performance oriented like WebSphere Application Server.

Application Server usually sits between Web Server and Database or another backend like messaging, etc.

Below is the typical diagram indicates application server located in the user requests.

application-server-location

Supported Platforms

WebSphere Application Server is supported on following platforms.

  • AIX
  • HP
  • IBM i
  • z/OS
  • Linux
  • Solaris
  • Windows

Alternatively, you may click here to go through official System Requirements document for WAS 8.5.5.

WebSphere Editions

There are seven WAS editions as following at the moment in the market.

  1. WebSphere Application Server – Liberty Core
  2. WebSphere Application Server – Express
  3. WebSphere Application Server – Base
  4. WebSphere Application Server – Network Deployment
  5. WebSphere Application Server – Hypervisor Edition
  6. WebSphere Application Server – z/OS
  7. WebSphere Application – Developers

Each edition is optimized for various requirements from development to production and small to enterprise business. You can compare them to choose the best suited for your business.

Click here to go through official WAS comparing sheet.

WebSphere Topologies

WebSphere provides configuration flexibility that can fit in any requirement in production or non-production environment within budget. Considering vast options, there could be various topologies, however; following three are most widely used.

  1. Standalone
  2. Network Deployment
  3. Administrative Agent

1. Standalone topology

It’s basic topology where you install WebSphere on a single server. By implementing this, you will have Cell, Node, and Server (JVM) on a single machine, which has some of the following limitations.

  • Won’t be able to start server from admin console
  • No high availability
  • No load balancing
  • All administrative tasks by connecting to JVM

Probably this would be good for development or no critical non-production environment. Below is the typical server diagram for standalone topology.

standalone-topology

2. Network Deployment topology

Probably the most used and advanced topology, which can have multiple JVM running on the same server or different server.

This is supported only with WebSphere Application Server Network Deployment edition.

The good thing about this topology is you can have all administrative tasks done including starting the JVM through DMGR console.

In this topology – DMGR and Node agent run as a separate process and it supports clustering for high-availability. Below is the basic diagram of ND topology.

ND-Topology

3. Administrative Agent topology

In this topology, an additional process called administrative agent is created which helps to manage multiple standalone servers registered to administrative agent.

This allows an administrator to manage all registered nodes using administrative agent console.

This becomes very useful when you have multiple standalone servers, and you wish to perform administrative tasks including starting JVM through a console. Below diagram illustrates a basic administrative agent topology.

admin-agent-topology

What’s new in WebSphere 8.5.5?

IBM released WebSphere Application Server 8.5 in June 2012 and 8.5.5 in June 2013 with some of the great features listed below.

  • HPEL – Binary logging which is faster than text logging. This helps in runtime performance.
  • Monitored directory support for faster edit-deploy-test cycles
  • JAVA SE7 – WAS 8.5 have the option to support Java 7 SE
  • Application Resiliency – WAS 8.5 ND is integrated with WebSphere virtual enterprise.
  • Health Management – Monitor the application server health and respond to the potential issues before an outage occurs.
  • SIP – Serviceability and troubleshooting enhancements to Session Initiation Protocol support more resilient processing of SIP sessions.

For the complete list of new features – click here to refer official document.

I hope this helps you in understanding IBM WebSphere application server.