: ZBFW (Zone-Based Firewall) and various IPsec configurations.
: Because it is an IOU image, you can run a complex topology with 20+ routers using less than 4GB of RAM. I86bi-linux-l3-adventerprisek9-ms.155-2.t.bin
: Compared to earlier 12.4 images or some of the buggier 15.2 releases, the 15.5(2)T build is known for being remarkably stable in virtualized environments. Implementation in Labs (GNS3 & EVE-NG) I86bi-linux-l3-adventerprisek9-ms.155-2.t.bin