In-Addr.arpa Domain; Dns Name Service; Name Servers - Novell NETWARE 6-DOCUMENTATION Manual

IN-ADDR.ARPA Domain

DNS Name Service

Name Servers

companya.com, which has authority over companya.com,
washington.companya.com, and providence.companya.com zones
chicago.companya.com, which has authority over the
chicago.companya.com zone
The IN-ADDR.ARPA domain (or zone) provides mapping of IP addresses to
names within a zone, enabling a client (or resolver) to request a hostname by
providing an IP address. Some security-based applications require this
function, also known as reverse-lookup.
The file that stores the IN-ADDR.ARPA data is made up of Pointer records
and additional name server records, including Start of Authority (SOA)
records, similar to other DNS zone files. Within the IN-ADDR.ARPA zone
file, IP addresses are listed in reverse order, and 'in-addr.arpa' is appended to
the address. A query for a host with an IP address of 1.2.3.4 would require a
PTR query with the target address of 4.3.2.1.in-addr.arpa.
DNS uses the name service component to provide the actual name-to-IP
address mapping that enables computers to locate each other on an
internetwork. The name service uses a client-server mechanism in which
clients query name servers for host address information.
DNS name servers maintain a database of information about hosts in a specific
zone. Each DNS zone must include a name server containing authoritative
information about all hosts within the zones it supports. A DNS name server
can be either a primary name server or a secondary name server.
In addition to local host information, name servers maintain information about
how to contact other name servers. Name servers in an internetwork are able
to contact each other and retrieve host information. If a name server does not
have information about a particular domain, the name server relays the request
to other name servers up or down the domain hierarchy until it receives an
authoritative answer for the client's query.
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Understanding