: The 15.7(3)M release reached its end-of-sale date in November 2020 .
license boot level advipservices (or securityk9 / appxk9) copy running-config startup-config reload C2951-universalk9-mz.spa.157-3.m8.bin
Here is a breakdown of the features and technical details contained within that specific file: : The 15
The universalk9 designation means the router contains code for all features, but specific capabilities must be activated via Cisco Software Activation Licenses (PAK keys). Group Encrypted Transport VPN (GET VPN)
Hardware-accelerated IPsec VPNs, Group Encrypted Transport VPN (GET VPN), and Dynamic Multipoint VPN (DMVPN).