{"id":5061,"date":"2012-07-15T18:43:26","date_gmt":"2012-07-15T23:43:26","guid":{"rendered":"http:\/\/bucktownbell.com\/?p=5061"},"modified":"2012-07-15T18:48:32","modified_gmt":"2012-07-15T23:48:32","slug":"ipid","status":"publish","type":"post","link":"http:\/\/bucktownbell.com\/?p=5061","title":{"rendered":"IPID"},"content":{"rendered":"<blockquote><p>\u00a0\u00a0\u00a0 The 16-bit IPID \ufb01eld carries a copy of the current value of a counter in a host\u2019s IP stack. Many commercial operating systems (including various versions of Windows and Linux versions 2.2 and earlier) implement this counter as a global counter. That is, the host maintains a single IPID counter that is incremented (modulo 216 ) whenever a new IP packet is generated and sent. Other operating systems implement the IPID counter as a per-\ufb02ow counter (as is done in the current version of Linux), as a random number, or as a constant, e.g., with a value of 0 ([1]).<\/p><\/blockquote>\n<p>From: <a href=\"ftp:\/\/gaia.cs.umass.edu\/pub\/Chen04_IPID.pdf\"><cite>ftp:\/\/gaia.cs.umass.edu\/pub\/Chen04_<strong>IPID<\/strong>.pdf<\/cite><\/a><\/p>\n<p>From: <a href=\"http:\/\/seclists.org\/bugtraq\/2001\/May\/44\"><span style=\"font-size: small;\"><strong>Fun with IP Identification Field Values <\/strong><\/span><\/a><\/p>\n<blockquote><p>RFC 791 gives a description about the IP Identification field.<\/p>\n<p>The identification field value is used to uniquely identify the fragments of<br \/>\na particular datagram. Fragments of a particular datagram are assembled if<br \/>\nthey have the same source, destination, protocol, and Identifier. The<br \/>\nidentifier is being chosen to be unique for this  &#8220;this source, destination<br \/>\npair and protocol for the time the datagram (or any fragment of it) could be<br \/>\nalive in the internet&#8221;[1].<\/p><\/blockquote>\n","protected":false},"excerpt":{"rendered":"<p>\u00a0\u00a0\u00a0 The 16-bit IPID \ufb01eld carries a copy of the current value of a counter in a host\u2019s IP stack. Many commercial operating systems (including various versions of Windows and Linux versions 2.2 and earlier) implement this counter as a &hellip; <a href=\"http:\/\/bucktownbell.com\/?p=5061\">Continue reading <span class=\"meta-nav\">&rarr;<\/span><\/a><\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[110],"tags":[719,323,331],"class_list":["post-5061","post","type-post","status-publish","format-standard","hentry","category-networking","tag-ip-2","tag-protocols","tag-rfc"],"_links":{"self":[{"href":"http:\/\/bucktownbell.com\/index.php?rest_route=\/wp\/v2\/posts\/5061","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/bucktownbell.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/bucktownbell.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/bucktownbell.com\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"http:\/\/bucktownbell.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=5061"}],"version-history":[{"count":5,"href":"http:\/\/bucktownbell.com\/index.php?rest_route=\/wp\/v2\/posts\/5061\/revisions"}],"predecessor-version":[{"id":5066,"href":"http:\/\/bucktownbell.com\/index.php?rest_route=\/wp\/v2\/posts\/5061\/revisions\/5066"}],"wp:attachment":[{"href":"http:\/\/bucktownbell.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=5061"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/bucktownbell.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=5061"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/bucktownbell.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=5061"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}