Record types

Each WHOIS database record has a field saying what type of record it is. The main NIC database contains records for individuals, domains, groups, hosts, networks, organizations, PSNs (formerly called IMPs), TACs, and gateways. It is advantageous to specify which type of record you are looking for since then WHOIS can present fewer, closer matches, and can also perform extra searches on fields specific to that record type, fields not ordinary searched in a general lookup. To search for a specific type of record, put one of the following keywords (shown with their minimum abreviation in all CAPS) before your target:
Arpanet
This finds only "host" records which are on net 10, the ARPANET. See below for a description of "hosts".
DOmain
Finds a domain record. Searches the usual places plus the domain-name field ("COM", "MIT.EDU", etc). You can match on any pre-dot portion of a domain name (that part of the name that precedes the dot). That is, "DOM MIT" would find MIT.EDU.
Gateway
Finds gateway records. Searches the same places as host, below.
HOst
Finds records for "hosts", meant more as "machines". Host records are found, as well as PSNs, TACs, and gateways. Looks in the hostname, nicknames, net-address, and domain-name fields, with bonus pre-dot AND pre-dash matching (i.e. matches text before the '.' or '-' in the name)! For example, "ho rutgers" finds RUTGERS.EDU, RUTGERS-GW.RUTGERS.EDU, and RED.RUTGERS.EDU, the last one found because RED's name field is "Rutgers University.
MIlnet
Like Arpanet, this keywords says to find only hosts that are on net 26, the MILNET.
NEtwork
Finds network records. Looks in net-name ("ARPANET", "S1NET", etc) and net-number ("10.0.0.0", "128.15.0.0", etc), with pre-dot matching on net number: "net 10" and "net 128.15" are eqvivalent to the above. "net 128" finds all networks with a first octet of 128.
Organization or Group
Finds org/group records. Looks in the usual places plus nicknames. Examples: "org rfc", "o net-sponsors".
PSn
Finds PSN records. Checks the usual places plus nicknames, PSN name, and PSN number. PSN names are like SRI51 and ROCK-ISLAND; "psn 1" will find you OBERURSEL-IMP (MILNET) and UCLA-IMP (ARPANET).
Tac
Finds TAC records. Looks in all the host places plus TAC-number, which is the BBN-assigned small number identifier for that TAC.
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