In 2005, the Department of Homeland Security commissioned Livermore National Labs to produce a kind of pre-emptive post-mortem report. Rather than wait for a vengeful ex-KGB hacker agent to ignite an American pipeline until it could be seen from space, the report issued recommendations for preventing an incursion that had yet never happened, from ever happening again.
 
Recommendation Number 1: Know your perimeter.
"The perimeter model is dead," pronounced Bruce Schneier, author of The New York Times' best seller Data and Goliath, and the CTO of IBM Resilient. "But there are personal perimeters. It doesn't mean there exists no perimeters. It just means it's not your underlying metaphor any more. So, I wouldn't say to anyone running a corporate network: There are no perimeters, zero."

"The traditional fixed perimeter model is rapidly becoming obsolete," stated the CSA's December 2013 white paper,” because of BYOD and phishing attacks providing untrusted access inside the perimeter, and SaaS and IaaS changing the location of the perimeter. Software defined perimeters address these issues by giving application owners the ability to deploy perimeters that retain the traditional model's value of invisibility and inaccessibility to ‘outsiders’, but can be deployed anywhere – on the internet, in the cloud, at a hosting center, on the private corporate network, or across some or all of these locations."

This reality invalidates the model of safeguarding the corporate network via the fortress model, one where all assets are inside and a well-defined perimeter exists, which can be defended. Instead, each asset requires a micro-fortress around it, regardless of where it is located. The EventTracker sensor enables a micro-fortress around and near the endpoint on which it operates. It provides host-based intrusion detection, data leak protection and endpoint threat detection. While the sensor itself operates on any Windows platform, it is able to act as a forwarder for any local syslog sources, relaying logs over an encrypted connection.
 
Welcome to your software defined perimeter.