{"draft":"draft-ietf-tcpm-tcp-dcr-07","doc_id":"RFC4653","title":"Improving the Robustness of TCP to Non-Congestion Events","authors":["S. Bhandarkar","A. L. N. Reddy","M. Allman","E. Blanton"],"format":["ASCII","HTML"],"page_count":"18","pub_status":"EXPERIMENTAL","status":"EXPERIMENTAL","source":"TCP Maintenance and Minor Extensions","abstract":"This document specifies Non-Congestion Robustness (NCR) for TCP.  In\r\nthe absence of explicit congestion notification from the network, TCP\r\nuses loss as an indication of congestion.  One of the ways TCP\r\ndetects loss is using the arrival of three duplicate acknowledgments.\r\nHowever, this heuristic is not always correct, notably in the case\r\nwhen network paths reorder segments (for whatever reason), resulting\r\nin degraded performance.  TCP-NCR is designed to mitigate this\r\ndegraded performance by increasing the number of duplicate\r\nacknowledgments required to trigger loss recovery, based on the\r\ncurrent state of the connection, in an effort to better disambiguate\r\ntrue segment loss from segment reordering.  This document specifies\r\nthe changes to TCP, as well as the costs and benefits of these\r\nmodifications.  This memo defines an Experimental Protocol for the Internet community.","pub_date":"August 2006","keywords":["[--------|e]","ncr","non-congestion robustness","transmission control protocol"],"obsoletes":[],"obsoleted_by":[],"updates":[],"updated_by":[],"see_also":[],"doi":"10.17487\/RFC4653","errata_url":"https:\/\/www.rfc-editor.org\/errata\/rfc4653"}