image on a 2800 series router provides a dense array of enterprise-grade functions: Release Notes for the Catalyst 2960-S, 2960-C, ... - Cisco
Release 15.2(1)T (September 2012) is the last “T” train for the 2800 series. Key updates over 12.4: c2800nm+adventerprisek9+mz+152+1+t+bin
That string is a Cisco IOS image filename: c2800nm-adventerprisek9-mz.152-1.T.bin — a 15.2(1)T release of the Enterprise K9 feature set for 2800-series routers. image on a 2800 series router provides a
: This part represents the IOS version.
The k9 designation signifies strong encryption, subject to U.S. export controls under EAR. Supported algorithms: c2800nm+adventerprisek9+mz+152+1+t+bin