Before joining Skype in 2004, Mr. Sauer was a Principal Network Security Architect for Sun Microsystems at its European research laboratory. Sauer is a member of the ACM, IEEE, Mensa and the Forum of Incident Response and Security Teams (FIRST). He holds a bachelor’s degree in Computer Engineering from Texas A&M University and is fluent in English and French.
What has been your biggest challenge as the CSO of Skype?
The most difficult challenge has been keeping up with the diversity and speed of the development initiatives going on in the company. Skype is growing by leaps and bounds – it still takes a finite amount of time to investigate the nuances of the interaction among new innovations. I remember the story told by Frederic Brooks about the development of early operating systems, which basically distills the idea that "adding people to a problem does not necessarily solve it faster." And this is equally true at Skype – it's not having a lot of people that counts, it's having bright and adaptable people that's important.
With the constant evolution of threats, what kind of technology challenges does Skype face?
One of the biggest potential threats to Skype is from attempts to conduct identity theft. Criminals and hackers are using increasingly sophisticated and targeted attacks against computer users worldwide to gain access to end-users' service and banking accounts. Internet users worldwide continue to fall prey to fake e-mail or so-called "phishing" attacks, supplying thieves with opportunities to install keystroke loggers and other malware on their computers. Skype works closely with eBay and PayPal, as well as with other industry partners, to identify and counter these and any other kinds of attacks.
How does Skype's security compare with that of other VoIP systems?
Skype uses a sophisticated system of standards-compliant cipher and digital signature systems to preserve the security and to ensure the integrity and authenticity of the call from end-to-end. Most other VoIP systems provide no encryption or authenticity controls over the call, which puts Skype in a security leadership class of its own.
Many argue that the adoption of VoIP brings together a whole new set of security risks and problems. What can be done to mitigate those risks?
Most of the problems identified in the area of VoIP have to do with the complexities of interconnecting VoIP switches and other hardware components in an enterprise configuration. In addition to this, there have been persistent arguments that VoIP is insecure because the vast majority of VoIP systems do not provide any level of encryption by default for their users.
Efforts in the VoIP industry to use encryption more pervasively, to reduce the risk of equipment configuration errors, and to reduce the amount of infrastructure components needed to deploy the service will help. Skype has a distinct advantage in this area because its peer-to-peer design eschews hardware switches, thereby eliminating the risk of misconfiguration, and uses only encrypted communications links.
What is your general strategy for making Skype more secure?
Keeping Skype simple to use and retaining a public key infrastructure-based (PKI) authentication system are the keys to ensuring continued security for Skype.