Feature history for loopback interfaces

Updated: April 24, 2026

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Details the feature evolution for loopback interfaces, outlining the key enhancements and updates across software releases.

Table 1. Feature History
Feature Name	Release Information	Description
Implicit ACL on Loopback Interfaces	Cisco IOS XE Catalyst SD-WAN Release 17.6.1a Cisco vManage Release 20.6.1	When a loopback TLOC interface has its own implicit ACL, ACL rules are applied on the traffic destined for the interface. With implicit ACL enabled on the loopback TLOC interface, only limited services can be allowed, thereby enhancing your network security. When a loopback TLOC interface is bound to a physical interface on a Cisco IOS XE Catalyst SD-WAN device, the physical interface is treated like a physical TLOC interface.

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