Validated digital signatures in an e-mail software application will:

A.
help detect spam.

B.
provide confidentiality.

C.
add to the workload of gateway servers.

D.
significantly reduce available bandwidth.

Explanation:
Validated electronic signatures are based on qualified certificates that are created by a certification
authority (CA), with the technical standards required to ensure the key can neither be forced nor
reproduced in a reasonable time. Such certificates are only delivered through a registration
authority (RA) after a proof of identity has been passed. Using strong signatures in e-mail traffic,
nonrepudiation can be assured and a sender can be tracked. The recipient can configure their email
server or client to automatically delete e-mails from specific senders. For confidentiality issues, one

must use encryption, not a signature, although both methods can be based on qualified certificates.
Without any filters directly applied on mail gateway servers to block traffic without strong
signatures, the workload will not increase. Using filters directly on a gateway server will result in an
overhead less than antivirus software imposes. Digital signatures are only a few bytes in size and will
not slash bandwidth. Even if gateway servers were to check CRLs, there is little overhead.