Martin Rehak

Principal Engineer

Cognitive Threat Analytics

Martin is a Principal engineer with Cisco Systems security group. He has been working in the area of machine learning, anomaly detection and network security. In the past, he was a Founder&CEO of Cognitive Security, acquired by Cisco in 2013. The VC-funded, spin-off company was created to develop a commercial technology based on the research performed by Martin and his team at Czech Technical University. Martin holds an engineering degree from Ecole Centrale Paris and a Ph.D. in AI from CTU in Prague


January 26, 2018


Securing Encrypted Traffic on a Global Scale

7 min read

written by Martin Rehak and Blake Anderson, on behalf of Cognitive and ETA teams Introduction How many engineers does it take to find malware in encrypted traffic? In case of...

November 13, 2015


How (not) to Sample Network Traffic

4 min read

This post has been authored by Karel Bartos and Martin Rehak The volume of the network traffic has been steadily increasing in the last years. In the same time, the delivery of critical services from cloud data centers has increased not only the volume of traffic, but also the complexity of transactions. High volumes of […]

October 15, 2015


Angler for Beginners in 34 Seconds

3 min read

Post authored by Martin Rehak, Veronica Valeros, Martin Grill and Ivan Nikolaev. In order to complement the comprehensive information about the Angler exploit kit from our Talos colleagues [

September 11, 2015


Cognitive Threat Analytics – Transparency in Advanced Threat Research

2 min read

Cisco Cognitive Threat Analytics is a security analytics product that discovers breaches in Cisco customer's networks by means of advanced statistical analysis, machine learning and global correlation...