Using FileAssurity

Key Manager - Key Generation - Valid To Date Guidelines

When FileAssurity generates keys for you the default date is set one calendar year from the date of creation. This may not be long enough to meet all your requirements.

You must consider your choice of the validity date carefully.  Long validity periods are usually appropriate. Public Trusted Authorities have keys in the browser that are valid for dates between 2009 and 2019. Provided you take adequate steps to protect your private keys there is no reason for them not to have long lives.

Public Trusted Authorities only provide keys with a one or two year life. This is partly because businesses and web sites change ownership quite frequently and so a one year check is necessary so they can control their liability.  If you are administering your own system you can take a view as to how long your keys should be valid for.