The WHOIS service is a distributed information system that allows querying Internet resources to obtain information on IP address or domain name holders.
LACNIC's WHOIS service allows querying information on Autonomous System Numbers and IP address blocks assigned by LACNIC. In addition, it allows obtaining information relating to these Internet resources, such as contact information for the organizations that hold them.
The WHOIS system was originally described in RFC 812, which was later obsoleted by RFC 3912 – "WHOIS Protocol Specification." As described in these documents, the original WHOIS system was designed as a tool for querying the points of contact of the organizations that were connected to the ARPANET at the time. The system does not specify which format should be used in the answers to the queries it receives. This is why different WHOIS servers provide information in different formats.
The server can be queried in two different ways:
The information provided by LACNIC's WHOIS service is organized as a list of values and attributes separated by a ":" character
When querying resources, either ASNs or IP address blocks, the answer returned includes, among others, the following attributes:
The point-of-contact information associated with this Internet resource is then presented. Returned attributes include:
When an IP block is queried, in addition to the attributes described above, there may also be DNS reverse delegation data available. Its attributes are as follows:
Even in the case of queries for IP address blocks that have been sub-assigned to other organizations, the data returned will refer to the sub-assignment's parent block, i.e., the original block from which the sub-assignment was made. In this case, "inetnum-up" is the attribute that is used.
In addition to ASN or IP address block queries, LACNIC's WHOIS system allows querying by point of contact handles. In this case the system will only return the point of contact's name, postal address, email and telephone number.
Finally, LACNIC's WHOIS system also allows querying by organization handles. In addition to the information mentioned above, the answer to this type of query will also include a list of all the Internet resources assigned to this organization. The attributes for this query are as follows:
Joint WHOIS is a project carried out by the five RIRs under the coordination of the NRO (Number Resource Organization) that aims at having a single entry point for all queries, regardless of the RIR holding the queried resources.
Currently, each RIR operates its own WHOIS query service which allows obtaining information regarding the Internet resources assigned by each RIR to organizations located in their own service regions.
This presents a problem for users: before querying for information about a resource they must first identify which RIR is responsible for the resource in question and then proceed to perform the WHOIS query against the corresponding RIR. In order to avoid this issue and make this procedure easier to use, working under NRO coordination, the Regional Registries have developed the Joint WHOIS service. This service provides a single point of entry for queries about any Internet resource regardless of the RIR to which the resources belong.
The Joint WHOIS system is basically a "proxy" that redirects the queries it receives towards the WHOIS server of the RIR holding the resource. When an RIR's server receives a query, it will identify the RIR responsible for the assignment and will immediately redirect the WHOIS query to that RIR. The answer will then be forwarded to the user.
Currently, the whois.lacnic.net server operates in this manner, i.e., as a Joint WHOIS proxy.