: Denotes that the image is digitally signed and verified by Cisco for authenticity and integrity. 03.06.10.e : This is the release train version (Version 3.6.10E). : This is the classic
Notes for the Catalyst 4500E Series Switch, Cisco IOS XE 3.6.xE cat3k-caa-universalk9.spa.03.06.10.e.152-2.e10.bin
Cisco IOS-XE Software Release Platform: Cisco Catalyst 3000 Series Switches (specifically Catalyst 3850, 3650, and similar "Cat3K" platforms) Release Train: 03.06.10.E (which maps to the mainline release 15.2(2)E10 ) Feature Set: universalk9 (Strong Cryptographic Features/Enterprise Services) Mode: spa (Shared Port Adapter architecture) : Denotes that the image is digitally signed
: This represents the software version. In Cisco's IOS XE software, which this seems to be a part of, the versioning can be critical for compatibility and feature support. This can be broken down further: cat3k-caa-universalk9.spa.03.06.10.e.152-2.e10.bin