All, (sending to tz@iana.org since tzdist@ietf.org appears to be dead) I was bored today (actually avoiding "real" work) and was playing around with the ESRI shapefile for timezones <http://efele.net/maps/tz/world/> I hacked up a quick extension to my tzdist implementation using the tz_world shapefile and basic ray tracing to be able to query a time zone by geo coordinates, similar to what Google offers in their Time Zone API. Note that I have yet to spend any time writing code to account for "holes" in time zones like the Navajo Reservation in Arizona. I modeled the extension after the "find" action in RFC 7808 but with lat/long query params rather than a glob pattern. A request and response for the timezone in which my home is located looks something like this: GET /tzdist/zones?latitude=43.070833&longitude=-78.831667 HTTP/1.1 { "synctoken": "890939292-1466089793", "timezones": [ { "tzid": "America/New_York", "etag": "6602582-1466089793", "last-modified": "2016-06-16T15:09:53Z", "publisher": "IANA Time Zone Database", "version": "2016e", "aliases": [ "US/Eastern" ] } ] } The definition of the extension looks like this in the capabilities response: { "name": "geolocate", "uri-template": "/zones{?latitude,longitude}", "parameters": [ { "name": "latitude", "required": true }, { "name": "longitude", "required": true } ] } Currently my code only accepts coordinates in decimal degrees, but I think it should probably support ISO 6709 formats. Is this something that folks would like to see documented as a formal extension to tzdist, either as specified above or with some modification? If so, I'd be willing to write it up as a draft and then move it through IETF in whatever fashion the ADs recommend. -- Kenneth Murchison Principal Systems Software Engineer Carnegie Mellon University