ASPF basic concepts

Single-channel protocol and multichannel protocol

Internal interface and external interface

On an edge device configured with ASPF to protect hosts and servers on the internal network, the interfaces on the device are divided into internal interfaces and external interface:

To protect the internal network, you can apply an ASPF in the outbound direction of the external interfaces or in the inbound direction of the internal interfaces of the device.

Zone pair

A zone pair specifies the source zone and destination zone of a traffic flow to be inspected:

For information about security zones, see Fundamentals Configuration Guide.