[consult] Additional background information

Member Services info at arin.net
Wed Mar 14 10:44:59 EDT 2007

The introductory post to consult at arin.net on this topic, 
http://lists.arin.net/pipermail/consult/2007-March/000001.html, states 
that the ARIN WHOIS query limit of 256 results has been in place since 
ARIN's inception as a means of curtailing data mining. As noted on the 
WHOIS help page, http://ws.arin.net/whois, queries that return more
than 256 results will stop displaying data after the 256th result.

This arbitrary limit was put in place both to control data mining and to
avoid undue server and bandwidth strain. An example illustrating the 
need for some type of limit is the query of "! n net-*". Without a 
limit, the result will be all 1.5+ million network records. Current 
functionality truncates it after the first 256 records.

In addition to truncating results, there is a query rate limiter in 
place to prevent excessive querying by a single IP address during a 
prescribed period of time.

Regarding other RIRs, RIPE WHOIS and AfriNIC WHOIS truncate responses
at 300 records. LACNIC WHOIS response results are limited by the number 
of bytes, not records. The maximum size for a LACNIC WHOIS result 
response is 65536 bytes. We will post APNIC's information upon receipt.

ARIN seeks input in order to determine the magnitude of the problem 
caused by the current 256 results limit. For those impacted by the 
limit, what alternative limit do you suggest and why?


Member Services
American Registry for Internet Numbers (ARIN)

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