Hello, Sunil,
you have a very very broad question. And I think it would be very difficult to answer it all. Usually, vendors provide you with hardware and software. The role of SI is to create a design, put it all together, testing it and support it. Vendors are there to provide you with support on such thing as fixing system bugs and possible suggestions on how you should proceed.
Unless you have done it before, starting on this kind of project by yourself is very very dangerous. The fastest site turnover I have seen so far was one month; however, on avergae we are talking about a three monthes to a year commitment.
Will you be subcontracting companies for each particular product, or will you attempt to do it all internally?
The really important things you have to worry about are:
will the vendor support your configuration
how much commitment is there AFTER the project is finished. Who will support what and how.
There are hundreds of consulting firms which specialize in developing procedures for call centers. If you have resources, use them.
One very important thing Genesys will NOT deal with you unless you are AT LEAST CGEcertified. Keep that in mind. This is a very very very important thing to consider. When something goes wrong, and you will email Genesys support, they will require that the person be CGE certified, or else they would not even approve of your call center, thus they will issue any kind of technical support even if it is a product bug.
If you have any specific questions about Genesys, fire away and I will try to help you as much as I can.
Cheers,
Kath