Class III Digital Signature is high level encryption used for tenders, etc.
"Obtaining a Digital Signature is mandatory in following cases:
There are three types of DSCs
For most business compliance, Class II digital signature suffices.
Digital Signatures usually come with a validity of one or two years. The validity of the DSC can be renewed once the term of the previous DSC expires. Under the present plan you get DSC with validity of 2 years.
Renewal of DSC is not part of the plan. For that, you will need to buy the DSC plan at the applicable rates. It is mandatory to inform the govt. authorities about the expiry of the old DSC and issue of a new one.