Ethernet IP TCP UDP 协议头部格式

The Ethernet header structure is shown in the illustration below:

以太网头部14 bytes

Destination

Source

Len

Data unit + pad

FCS

(6 bytes)

(2)

(46-1500 bytes)

(4 bytes)

Ethernet header structure

The IP header structure is as follows:

IP头部20 bytes

4

8

16

32 bits

Ver.

IHL

Type of service

Total length

Identification

Flags

Fragment offset

Time to live

Protocol

Header checksum

Source address

Destination address

Option + Padding

Data

IP header structure

The TCP header structure is as follows:

TCP头部20 bytes

Source port

Destination port

Sequence number

Acknowledgement number

Offset

Resrvd

U

A

P

R

S

F

Window

Checksum

Urgent pointer

TCP header structure

The UDP header structure is shown as follows:

UDP头部8 bytes

Length

UDP header structure

一些协议头部的定义：

    本文转自阿凡卢博客园博客，原文链接：http://www.cnblogs.com/luxiaoxun/archive/2012/08/08/2628627.html，如需转载请自行联系原作者