You can now access Cisco Modeling Labs (CML) for free! Thanks to Cisco DevNet, you use a cloud based version of CML for free. All you need is your web...Cisco Modeling Labs is our premier network simulation tool, with real Cisco software. The platform lets you build highly reliable models for designing, testing, and troubleshooting. With the comprehensive API, you can develop network automation as well -- all for a fraction of the cost, hassle, and energy requirements of a physical lab. New Announcement. Sign up free Log in. DevNet Cisco has released security updates to address SaltStack FrameWork vulnerabilities in Cisco Modeling Labs Corporate Edition (CML) and Virtual Internet Routing Lab Personal Edition (VIRL-PE). A remote attacker could exploit these vulnerabilities to take control of an affected system.