PortNort

Harsh and I are both Master's students at JHUISI, so we are always thinking about security. Unsecured connections make us cringe, forms without validation make us tear our hair out, and the thought of manual memory management leaves us cowering in the corner.

Worse than all of these specters, though, is an open wifi connection. Putting traffic on a public network is a nightmare; anyone with internet access and a quiet conscience can read it, and anyone with a little expertise on top has a good chance of being able to exploit it. However, not all people have the luxury of being able to remain online. In a sad piece of irony, such public networks are regularly used by the people who have the most to lose.

With this in mind, we created PortNort, a simple pocket-portable network security solution. For the prospective user, it's a simple device. One simply connects PortNort to the wifi network, then connects himself to PortNort. WIth that simple gesture, she has given herself all of the protection Harsh and I have hidden under the hood.

Should one wish to pry PortNort open however, he would find a great deal more. First, a whole host of simple network hardening tricks. This layer includes things like checking the MAC of a router (to ensure that it hasn't been spoofed), filtering out reverse-path packets (to avoid leaking private IP space), and ignoring ICMP redirects (to prevent Man-in-the-Middle attacks). Second, an aggressive firewall which blocks invalid TCP flags, optimizes DNS queries, drops suspected traceroutes, and blocks outbound malware connections. The keystone piece is the Snort suite, an open source intrusion prevention system capable of real-time traffic analysis and packet logging.

Together, these systems create a level of security superior to that which nearly any user enjoys when working from his own home, or even from many small offices. PortNort is particularly well-suited to business people, doctors, lawyers, and anyone else who needs a security solution but finds the current offerings too complicated, too expensive, or simply too bulky to bring on flights.

_ PortNort: Common sense in a box _