http://en.zaoniao.it/index.php?action=history&feed=atom&title=IPv4_header_checksum 2026-05-15T09:25:36Z Revision history for this page on the wiki MediaWiki 1.32.0 http://en.zaoniao.it/index.php?title=IPv4_header_checksum&diff=5443&oldid=prev 2019-06-03T04:32:02Z

<p>Created page with &quot;{{#seo: |title=IPV4 Header Checksum – Internet Protocol – zaoniaoWiki |keywords=ipv4 header checksum,ipv4,ipv4 header checksum calculation,internet protocol ipv4 |descript...&quot;</p> <p><b>New page</b></p><div>{{#seo:<br /> |title=IPV4 Header Checksum – Internet Protocol – zaoniaoWiki<br /> |keywords=ipv4 header checksum,ipv4,ipv4 header checksum calculation,internet protocol ipv4<br /> |description=IPv4 header checksum is a simple checksum used in version 4 of the Internet Protocol (IPv4) to protect the header of IPv4 data packets against data corruption<br /> }}<br /> &lt;amp/&gt;<br /> [[File:IPV4 Header Checksum.png|300px|right|IPV4 Header Checksum foto]]<br /> The '''IPv4 header checksum''' is a simple checksum used in version 4 of the Internet Protocol (IPv4) to protect the header of IPv4 data packets against data corruption. This checksum is calculated only for the header bytes (with the checksum bytes set to 0), is 16 bits long and is a part of the P packet header.<br /> ==Description==<br /> The checksum is calculated by forming the ones' complement of the ones' complement sum of the header's 16-bit words. The result of summing the entire '''IP header''', including checksum, should be zero if there is no corruption. At each hop, the checksum is recalculated and the packet will be discarded upon checksum mismatch. The router must adjust the checksum if it changes part of the IP header (such as when decrementing the TTL.) <br /> {{#ev:youtube|JqEvNxAJtDk|500|right|The IP Header Checksum}}<br /> The '''IPv6''' protocol lacks a header checksum: its designers considered that the whole-packet link-layer checksumming provided in layer 2 transports such as '''PPP''' and Ethernet, combined with the use of checksums in upper-layer protocols such as TCP and UDP, were sufficient to make a separate header checksum unnecessary.<br /> <br /> == See also ==<br /> * [[Header check sequence]]<br /> * [[Checksum]]<br /> <br /> == External links ==<br /> * [http://www.tcpipguide.com/free/t_IPDatagramGeneralFormat.htm IP Datagram General Format]<br /> * [http://everything2.com/index.pl?node_id=441121 Header Checksum]<br /> <br /> ==Source==<br /> <br /> [http://wikipedia.org/ http://wikipedia.org/]<br /> [[Category:Error-detecting codes]]<br /> [[Category:Error-correcting codes]]</div>

Admin