Does anybody knows how many searches are needed to get some IP banned from whois searches on whois.internic.net ?
I wouldnt think you would get banned if you were doing searches at that whois. Unless your IP and something with a spider/bot, automated script or what not.
I never heard of getting banned before, but I do know each IP has a daily limit. Not to sure what is it, but I would guess around 10.
Registrars and third party WHOIS lookup services can "ban" you from using it for an indefinite period of time if they wish. And they won't tell you what's the limit.
it depends which whois server you use, if you use a DAS (domain availability server) then there is no limit on the number of queries you can have. I used to do ~ 20,000 lookups per day and never got banned