To a router, a flow is a (1) of packets that share the same characterstics, such as traveling the same (2) , using the same (3) , having the same kind of security, and so on. A router that suppors the handling of flow labels has a (4) table. The table has an entry for each active flow label; each entry defines the (5) required by the corresponding flow label.

2（）

A．path

B．rout

C．circuit

D．way

如果在查询的条件中使用了通配符方括号“[]”，它的含义是( )。

A．通配任意长度的字符

B．通配不在括号内的任意字符

C．通配方括号内列出的任一单个字符

D．错误的使用方法