{"draft":"draft-ietf-alto-xdom-disc-06","doc_id":"RFC8686","title":"Application-Layer Traffic Optimization (ALTO) Cross\u2011Domain Server Discovery","authors":["S. Kiesel","M. Stiemerling"],"format":["HTML","TEXT","PDF","XML"],"page_count":"34","pub_status":"PROPOSED STANDARD","status":"PROPOSED STANDARD","source":"Application-Layer Traffic Optimization","abstract":"The goal of Application-Layer Traffic Optimization (ALTO) is to\r\nprovide guidance to applications that have to select one or several\r\nhosts from a set of candidates capable of providing a desired\r\nresource.  ALTO is realized by a client-server protocol.  Before an\r\nALTO client can ask for guidance, it needs to discover one or more\r\nALTO servers that can provide suitable guidance.\r\n\r\nIn some deployment scenarios, in particular if the information about\r\nthe network topology is partitioned and distributed over several ALTO\r\nservers, it may be necessary to discover an ALTO server outside of\r\nthe ALTO client's own network domain, in order to get appropriate\r\nguidance.  This document details applicable scenarios, itemizes\r\nrequirements, and specifies a procedure for ALTO cross-domain server\r\ndiscovery.\r\n\r\nTechnically, the procedure specified in this document takes one\r\nIP\u00a0address or prefix and a U-NAPTR Service Parameter (typically,\r\n\"ALTO:https\") as parameters. It performs DNS lookups (for NAPTR\r\nresource records in the \"in-addr.arpa.\" or \"ip6.arpa.\" trees) and\r\nreturns one or more URIs of information resources related to that IP\r\naddress or prefix.","pub_date":"February 2020","keywords":["Application-Layer Traffic Optimization (ALTO)","ALTO cross-domain server discovery","ALTO third-party server discovery"],"obsoletes":[],"obsoleted_by":[],"updates":[],"updated_by":[],"see_also":[],"doi":null,"errata_url":null}