Ken Harrenstien RFC-811 Vic White 1 March 1982 Elizabeth Feinler Network Information Center SRI International
The NIC Internet Hostnames Server is an NCP/TCP-based host
information program and protocol running on the SRI-NIC
machine. It is one of a series of ARPANET/Internet name
services maintained by the Network Information Center (NIC) at
SRI International on behalf of the Defense Communications
Agency (DCA). The function of this particular server is to
deliver machine-readable name/address information describing
networks, gateways, hosts, and eventually domains, within the
internet environment. As currently implemented, the server
provides the information outlined in the DoD Internet Host
Table Specification (RFC 810).
The name server accepts simple text query requests of the form
<command key> <argument(s)> [<options>]
where square brackets ("[]") indicate an optional field. The command key is a keyword indicating the nature of the request. The defined keys are explained below.
The response, on the other hand, is of the form
<response key> : <rest of response>
where <response key> is a keyword indicating the nature of the response, and the rest of the response is interpreted in the context of the key.
The currently defined keywords are:
Command Keys:
HNAME (find entry with given name) HADDR (find entry with given address) ALL (return entire host table)
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ERR (entry not found, nature of error follows) NET (entry found, rest of entry follows) GATEWAY (entry found, rest of entry follows) HOST (entry found, rest of entry follows) BEGIN (followed by multiple entries) END (done with BEGIN block of entries)
More keywords will be added as new needs are recognized. A more detailed description of the allowed requests/responses will follow.
To access this server from a program, connect to service host (SRI-NIC)
TCP: port 101 decimal
NCP: socket 101 decimal for ICP
send the information query, and await the response.
Note: Care should be taken to interpret the nature of the
reply (e.g, single record or multiple record), so that no
confusion about the state of the reply results. An "ALL"
request will likely return several hundred or more records of
all types (see RFC 810), whereas "HNAME" or "HADDR" will
usually return one HOST record, or "BEGIN:", list of host
records, "END:", if there is more than one match.
HNAME SRI-NIC <CRLF> ;where <CRLF> is a carriage return/ linefeed, and 'SRI-NIC' is a host name
The likely response is:
HOST : 10.0.0.73 : SRI-NIC,NIC : FOONLY-F3 : TENEX : NCP :
A response may stretch across more than one line.
Continuation lines always begin with at least one space.
For example:
HOST : 10.0.0.73 : SRI-NIC,NIC : FOONLY-F3 : TENEX : NCP :
HADDR 10.0.0.73 <CRLF> ;where <CRLF> is a carriage return/ linefeed, and '10.0.0.73' is a host address
The likely response is the same as for the HNAME request:
HOST : 10.0.0.73 : SRI-NIC,NIC : FOONLY-F3 : TENEX : NCP :
ALL <CRLF> ;where <CRLF> is a carriage return/linefeed
The likely response is the keyword 'BEGIN' followed by a colon ':', followed by the entire internet host table in the format specified in RFC 810, followed by 'END:'. For example:
BEGIN:
NET : 10.0.0.0 : ARPANET :
NET : 18.0.0.0 : LCSNET :
GATEWAY : 10.0.0.77, 18.8.0.4 : MIT-GW :: MOS : IP/GW :
HOST : 10.0.0.73 : SRI-NIC,NIC : TENEX : FOONLY-F3
NCP/TELNET, NCP/FTP, TCP :
HOST : 10.2.0.11 : SU-TIP, FELT-TIP ::
END:
ERR : <code> : <string> :
as in
ERR : NAMNFD : Name not found :
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NAMNFD -- Name not found; name not in table ADRNFD -- Address not found; address not in table ILLCOM -- Illegal command; command key not recognized TMPSYS -- Temporary system failure, try again later
The host name server described above runs over a single global
internet host name/address data base. This data base is an
extension of the old ARPANET Hosts.txt file, and is being
maintained by the NIC to provide continuity during the
transition and expansion to the internet environment. We view
the central administration of a global host name data base,
along with this simple name server, as an interim solution on
the way to a decentralized, distributed name/address
translation service. The NIC welcomes your comments and
suggestions for such an expanded service. Send comments to
NIC@SRI-NIC.