Release Notes for Catalyst 3750-X, 3750-E, 3560-X ... - Cisco
: The universal image allows users to activate different feature sets (IP Base, IP Services) via license keys without needing to swap the underlying binary file. Installation and Upgrade Procedure c3750e-universalk9-mz.150-2.se11.bin
: The executable binary format used for Cisco IOS images. Technical Details: File Size : Approximately 20.44 MB (20,442,368 bytes). Release Notes for Catalyst 3750-X, 3750-E, 3560-X
: Indicates the "Universal" feature set, which includes advanced security features like strong encryption (K9). Release Notes for Catalyst 3750-X
: The software version (15.0) and the specific maintenance release (SE11).
: Provides line-rate performance for IPv4 and IPv6 switching.
: Supports high-speed stacking of up to nine switches, allowing them to operate as a single logical unit.