C3900-universalk9-mz.spa.157-3.m8.bin |verified| 【ULTIMATE • Playbook】

: A "Universal" image containing all features (Security, Unified Communications, Data) that are unlocked via Cisco Software Licensing. The "k9" indicates it supports payload encryption. mz : Indicates the file is memory-resident and compressed. SPA : Digitally signed by Cisco for authenticity.