DNSSEC validation for a local Bind

[Roberto Carna]

Dear, I have a local Bind which resolves local hostnames from my
company. It doesn't connect to any DNS from Internet at all.

Is it useful to set up DNSSC validation in order to avoid possible
attacks (like cache poisoning or man in the middle) from my LAN ???
Because I've read about this technique and it's too hard for
implementing.

Thanks a lot !!!