Grand Challenges in Networking Nick Feamster CS 7001

Network Security & Operations Goal: Improve network reliability and availability in the face of both accidental and malicious faults Sub-areas –Reliability: fast recovery from failures –Efficiency: improving the efficiency of the Internets connectivity markets –Security and trust: spam filtering, phishing, etc. –Management: fault diagnosis, provisioning, etc. –Accessibility: defeating the great firewall of China

Reliability Step 1: Run multiple instances of the routing protocol, each with slightly perturbed versions of the configuration Step 2: Allow traffic to switch between instances at any node in the protocol t s Compute multiple forwarding trees per destination. Allow packets to switch slices midstream. Joint with Prof. Santosh Vempala Student: Murtaza Motiwala

Paths become longer simply because two ASes decide not to interconnect Comcast Abilene AT&T Cogent $$ Peering points in Atlanta Peering point in Washington, D.C. Structure of Internet paths Exploit new structure to allow new types of contracts Efficiency Two Changes Joint with Prof. Vijay Vazirani and Prof. Ramesh Johari (Stanford)

Trust Many applications rely on trusted communications between end hosts Social networks contain rich information about interpersonal relationships (How) can the trust that is inherent in these relationships be used to bootstrap trusted communications at the network layer? –Access control –File sharing / Cooperative backup –Key exchange

Transparency ISPs are increasingly applying discriminatory access to different ISPs, application traffic, etc. Problem: Can data that is passively collected from end users be used to distinguish normal degradations (e.g., due to transient failure, congestion, etc.) from intentional discrimination?

Accessibility 59+ countries block access to content on the Internet –News, political information, etc. Idea: Use the increasing amount of user-generated content on the Internet (e.g., photo-sharing sites) as the basis for covert channels Some problems: –How do publishers and consumers agree on places to exchange content? –How to design for robustness against blocking? –How to provide deniability for users? –Incentives for participation –System design and implementation

Networking Faculty and Projects Mostafa Ammar –Delay-tolerant networks, multi-layer network architectures Constantine Dovrolis –Network measurement, evolution of network graphs Jim Xu –Data streaming, data structures for network measurement, network security Ellen Zegura –Network topology, networks in developing regions