in-addr.arpa domain

[Milan Yagodich]

Hi-
I don't understand how reverse lookups are managed/stored.  When you
query any nameserver with an IP address, you get the domain name.  
In my case, a query for mycomm.com turns up my ip address.
mycomm.com      internet address = 205.252.165.66        

and a reverse inquiry, yields my isp (mycomm.com is a virtual domain
under websp.com)
66.165.252.205.in-addr.arpa     name = websp.websp.com   

Does the in-addr.arpa domain reside at the rootservers?

The basis for my question is this.  I am going to move mycomm.com from
its virtual host to my own machine when the DSL gets hooked up.  I plan
on running my own nameservers.

I did a reverse lookup on my new block of addresses and got
xxx.xxx.xxx.xxx-sdsl.line.cais.net.  If my nameservers have the correct
A and PTR records for mycomm.com, which domain name will get returned
when I do a reverse query on my new address?

How does the in-addr.arpa domain know which is the correct PTR record?

Thanks in advance.
Milan
-- 
Milan Yagodich
milan at mycomm.com
http://www.mycomm.com
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