{"draft":"draft-ietf-mpls-special-purpose-labels-06","doc_id":"RFC7274","title":"Allocating and Retiring Special-Purpose MPLS Labels","authors":["K. Kompella","L. Andersson","A. Farrel"],"format":["ASCII","HTML"],"page_count":"11","pub_status":"PROPOSED STANDARD","status":"PROPOSED STANDARD","source":"Multiprotocol Label Switching","abstract":"Some MPLS labels have been allocated for specific purposes.  A block\r\nof labels (0-15) has been set aside to this end; these labels are commonly\r\ncalled \"reserved labels\".  They will be called \"special-purpose                      \r\nlabels\" in this document.\r\n\r\nAs there are only 16 of these special-purpose labels, caution is\r\nneeded in the allocation of new special-purpose labels; yet, at the\r\nsame time, forward progress should be allowed when one is called for.\r\n\r\nThis memo defines new procedures for the allocation and\r\nretirement of special-purpose labels, as well as a method to extend\r\nthe special-purpose label space and a description of how to handle\r\nextended special-purpose labels in the data plane.\r\nFinally, this memo renames the IANA\r\nregistry for special-purpose labels to \"Special-Purpose MPLS Label Values\" and\r\ncreates a new registry called the \"Extended Special-Purpose MPLS Label               \r\nValues\" registry.\r\n\r\nThis document updates a number of previous RFCs that use the term\r\n\"reserved label\".  Specifically, this document updates RFCs 3032,\r\n3038, 3209, 3811, 4182, 4928, 5331, 5586,\r\n5921, 5960, 6391, 6478, and 6790.","pub_date":"June 2014","keywords":[],"obsoletes":[],"obsoleted_by":[],"updates":["RFC3032","RFC3038","RFC3209","RFC3811","RFC4182","RFC4928","RFC5331","RFC5586","RFC5921","RFC5960","RFC6391","RFC6478","RFC6790"],"updated_by":["RFC9017"],"see_also":[],"doi":"10.17487\/RFC7274","errata_url":null}