首先看IPv4包头如下
其中,Qos用到的是Tos定义有下面两种:
老的IPv4 TOS Byte定义和值
新的DSCP定义和值
DSCP值
DSCP Value |
Meaning |
Drop Probability |
Equivalent IP Precedence Value |
101 110 (46) |
High Priority Expedited Forwarding (EF) |
N/A |
101 – Critical |
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