Santos:CCNA Sec 210-260 OCG

The Self Zone

Traffic directed to the router itself (as opposed to traffic going through the router as transit traffic that is not destined directly to the router) involves the self zone. Traffic destined to the router, regardless of which interface is used, is considered to be going to the self zone. Traffic being sourced from the router is considered to be coming from the self zone. By default, all traffic to the self zone or from the self zone (which really means all traffic from the router or to the router) is allowed. However, if you want to create policies related to traffic to or from this self zone, you do it the same way by creating zone pairs and assigning a policy to the zone pair. Table 15-4 describes self zone traffic behavior.