Describes the role and enforcement of implicit ACLs on loopback interfaces, emphasizing security implications and default access behavior.
Implicit ACLs on loopback interfaces are access control mechanism that
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consist of default rules applied to traffic destined for loopback interfaces,
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can be present by default or enabled through configuration to limit or permit traffic, and
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is applied to traffic destined for loopback interfaces configured with a Transport Location (TLOC) in both bind mode (bound to a physical interface) and unbind mode (not bound to any physical interface) on Cisco IOS XE Catalyst SD-WAN devices.
Benefits
Implicit ACL on a loopback TLOC interface protects against denial of service (DoS) attacks by allowing only limited services. This enhances your network security.