{"draft":"draft-ietf-pim-ecmp-05","doc_id":"RFC6754","title":"Protocol Independent Multicast Equal-Cost Multipath (ECMP) Redirect","authors":["Y. Cai","L. Wei","H. Ou","V. Arya","S. Jethwani"],"format":["ASCII","HTML"],"page_count":"12","pub_status":"PROPOSED STANDARD","status":"PROPOSED STANDARD","source":"Protocols for IP Multicast","abstract":"A Protocol Independent Multicast (PIM) router uses the Reverse Path\r\nForwarding (RPF) procedure to select an upstream interface and router\r\nin order to build forwarding state.  When there are equal cost\r\nmultipaths (ECMPs), existing implementations often use hash\r\nalgorithms to select a path.  Such algorithms do not allow the spread\r\nof traffic among the ECMPs according to administrative metrics.  This\r\nusually leads to inefficient or ineffective use of network resources.\r\nThis document introduces the ECMP Redirect, a mechanism to improve\r\nthe RPF procedure over ECMPs.  It allows ECMP selection to be based\r\non administratively selected metrics, such as data transmission\r\ndelays, path preferences, and routing metrics.  [STANDARDS-TRACK]","pub_date":"October 2012","keywords":[],"obsoletes":[],"obsoleted_by":[],"updates":[],"updated_by":["RFC8736","RFC9436"],"see_also":[],"doi":"10.17487\/RFC6754","errata_url":null}