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 supports 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.

3（）

A．source

B．resources

C．route

D．Entry

按照应急演练的形式，可分为现场演练和（）。

A.桌面演练

B.专项演练

C.综合演练