These images are proprietary and officially distributed as part of the Cisco Modeling Labs (CML) (formerly VIRL) software suite. Cross Platform Release Notes for Cisco IOS Release 15.7(3)M
: The 15.7(3)M3 release is known for being stable within virtualized environments, suffering from fewer "ghost" bugs than older 15.2 or 15.4 versions. How to Download vios-adventerprisek9-m.vmdk.spa.157-3.m3 vios-adventerprisek9-m.vmdk.spa.157-3.m3 download