By Dr. R. Srinivasan, CTO, iCMG, Bangalore

In my previous article, I have given the illustration of a typical architecture for the e-Governance, with CORBA/IIOP as the defacto middleware standard. Whatever may be the middleware chosen, the system should be highly reliable, must have capability for future expansion, must be able to be managed with ease, must have high performance but above all should have very good security in transactions. In order to achieve this an EAI system, like e-Governance, must have some built-in services which will not only make the applications to have smooth interactions but also make the users feel that the entire operation is user friendly. Every vendor of a typical middleware like IONA, BEA, Netweave, etc. provide these services.

Normally the services can be divided into Essential Services and Optional/Additional Services and a brief description is given below:

1. Transaction Service: Particularly in a distributed environment in e-Governance this is an important service through which any request, from a common man or any other person from a department, is issued to any application, the service enables access to the respective application server to come up with an immediate response.
   
   
2. Security Service: Any transaction over a common medium like internet should be highly secured. This service in a middleware provides both data security and access security. Access security is provided through proper authentication and authorisation where as data/information security is through encryption/decryption techniques.
   
   
3. Directory Service: This is for user and global resource management so that data and servers to be freely moved about the network. This service will allow a client to access a remote file or a table without any need for the client knowing the exact location of these objects in the network.
   
   
4. File Transfer Service: This will enable smooth transfer of large files around the application network with recovery features just incase of network failures.
   
   
5. Queuing Service: E-Governance while implemented must be a real distributed processing system with many application servers distributed across the network but connected through the middleware. This will involve communication from peer-to-peer. The Queuing service provides guaranteed delivery of message from one peer to the other under conditions like heavy network traffic, failure of network or remote platforms, etc.
   
   
6. Broadcast Services: With the plan of establishing Information Kiosks not only in Urban Sectors but also in Rural areas under e-Governance, it is necessary to distribute the vital information to large areas ad this is provided by the broadcasting service

By incorporating these services it could be seen that the middleware will have the capability of having "fault tolerance" and "load balancing". Fault tolerance is the ability to cope with and to recover from various faults like fatal application server process fault, server hardware fault and network fault. The middleware should also have the feature to route messages between different networks in the system of e-Governance, even if they use different communication protocols.

As discussed in the last article CORBA/IIOP has all these features and hence the defacto standard middleware of the future.