I'm using Ubunutu 10.04 and doing whois queries on a list of domains. I've got very limited knowledge about the whois system and have some specific questions that I've found difficult to find specific answers on. I'm not even sure if this is the right place to ask the question, if its not please direct me to where I should ask it, thanks.
As far as I understand it ubuntu's whois service queries a set (or maybe 1) known whois server on port 43 for the parameter passed in. This server in turn keeps a database of whois information. I've heard of thick vs. thin whois servers where thick servers have the information locally and thin servers knowing where to get it.
Is there a rate limit to utilizing this service, and if so what is it? Is it known? Who sets it? Is it per ip address? How do "they" handle determining who the rate limit is coming from?
I'm trying to better understand the whois service and how it works.