Hi All

[Servet Zeybek]

     I am working with DNS requests and responds for some time and i have
some questions!!! (Im reading RFC 1035 but the info is not very clear for
every request type)

1 - MG (Mail Group Member): In RFC it says:  " A <domain-name> which
specifies a mailbox which is a member of the mail group specified by the
domain name" lets say, I have the name "example.com" to lookup  with this
type of query(MG), does example.com specify a group? what does this query
exactly mean? what should the answer be? When i try to look up the address
(www.hotmail.com) i get a SOA answer, the address(www.google.com) i get a
CNAME answer. Here i got confused, why 2 different answers, and why SOA and
CNAME!!
2- MR (Mail rename domain name): RFC says; "A <domain-name> which specifies
a mailbox which is the proper rename of the specified mailbox". Does that
mean;  the name (example.com)  is assigned a mailbox(MB request), and MR
gives an alternative mailbox for example.com? When i try this MR query with
(www.google.com) i get a CNAME answer!!! isnt this illogical?
3- NULL : What is the purpose of this request? When i try this with
www.google.com, i get a CNAME answer and with www.hotmail.com i get a SOA
answer!!
4- PTR(Domain name Pointer): how different is this from CNAME?
5- what is "additional section processing"? I see this in RFC 1035?

    I would be obliged if you could give your ideas about these!
    Thanks a lot

     Servet