{"draft":"draft-ietf-behave-ftp64-12","doc_id":"RFC6384","title":"An FTP Application Layer Gateway (ALG) for IPv6-to-IPv4 Translation","authors":["I. van Beijnum"],"format":["ASCII","HTML"],"page_count":"16","pub_status":"PROPOSED STANDARD","status":"PROPOSED STANDARD","source":"Behavior Engineering for Hindrance Avoidance","abstract":"The File Transfer Protocol (FTP) has a very long history, and despite\r\nthe fact that today other options exist to perform file transfers,\r\nFTP is still in common use.  As such, in situations where some client\r\ncomputers only have IPv6 connectivity while many servers are still\r\nIPv4-only and IPv6-to-IPv4 translators are used to bridge that gap,\r\nit is important that FTP is made to work through these translators to\r\nthe best possible extent.\r\n\r\nFTP has an active and a passive mode, both as original commands that\r\nare IPv4-specific and as extended, IP version agnostic commands.  The\r\nonly FTP mode that works without changes through an IPv6-to-IPv4\r\ntranslator is extended passive.  However, many existing FTP servers\r\ndo not support this mode, and some clients do not ask for it.  This\r\ndocument specifies a middlebox that may solve this mismatch.  \r\n[STANDARDS-TRACK]","pub_date":"October 2011","keywords":["[--------]","FTP","SIIT","NAT64"],"obsoletes":[],"obsoleted_by":[],"updates":[],"updated_by":[],"see_also":[],"doi":"10.17487\/RFC6384","errata_url":null}