The Internet Protokoll (IP) V4, defined in the RFC791, is the routing layer service of the TCP/IP network.
Type of Service/
|Flags | Fragment offset|
Time to Live
Options + Padding
|Vers||Version - mark the used version of the IP-protocol, "4" for V4|
|IHL||Internet Header Length - length of the IP-Header in units of 32 bits (min. 5)|
|Type of Service
Establishing of a service kindliness - for example priority, dilatory installment, reliability
The DSCP Feld, defined in the RFC2474, replaces the Type Of Sevice Feld (RFC3168) for IPv4
|total length||total length (header + data) of the IP datagram|
|Identification||for reassembling of fragments|
|Fragment offset||position of the current fragment in the datagram in units of 64 bits|
|Time to Live||Lifespan during handling by router (discarding of the datagram with 0)|
|Protocol||Transportation protocol (TCP,UDP,ICMP,...)|
|Header checksum||Checksum of the harder, recalculation through each router (without data)|
|Source address||senders IP-address|
|Destination address||receivers IP-address|
|Options + Padding||optional parameters (0..40 bytes)|
plus filling byte on 32-bit-borders
IP version 6 (IPv6) is the new version of the Internet Protokoll based on IPv4.
Additional services and a widened IP-address room were integrated. The options of the IPv6 are placed on that occasion in a seperatem header between the IPv6 header and the Transportlayer header.