{"draft":"draft-ietf-pals-ethernet-cw-07","doc_id":"RFC8469","title":"Recommendation to Use the Ethernet Control Word","authors":["S. Bryant","A. Malis","I. Bagdonas"],"format":["ASCII","HTML"],"page_count":"9","pub_status":"PROPOSED STANDARD","status":"PROPOSED STANDARD","source":"Pseudowire And LDP-enabled Services","abstract":"The pseudowire (PW) encapsulation of Ethernet, as defined in\r\nRFC 4448, specifies that the use of the control word (CW) is\r\noptional.  In the absence of the CW, an Ethernet PW packet can be\r\nmisidentified as an IP packet by a label switching router (LSR).\r\nThis may lead to the selection of the wrong equal-cost multipath\r\n(ECMP) path for the packet, leading in turn to the misordering of\r\npackets.  This problem has become more serious due to the deployment\r\nof equipment with Ethernet Media Access Control (MAC) addresses that\r\nstart with 0x4 or 0x6.  The use of the Ethernet PW CW addresses this\r\nproblem.  This document RECOMMENDS the use of the Ethernet PW CW in\r\nall but exceptional circumstances.\r\n\r\nThis document updates RFC 4448.","pub_date":"November 2018","keywords":["pseudowire","PW","CW","ECMP","MAC address","out of order","ordering"],"obsoletes":[],"obsoleted_by":[],"updates":["RFC4448"],"updated_by":[],"see_also":[],"doi":"10.17487\/RFC8469","errata_url":"https:\/\/www.rfc-editor.org\/errata\/rfc8469"}