The 2nd NDN Project Retreat

February 5th, 2012 by kc

I kicked off 2012 with a visit to Colorado State University in Fort Collins, CO to attend the principal investigators (PI) retreat for the Named Data Networking Project, one of four projects funded under NSF’s “Future Internet Architecture” (FIA) program. Impressive progress since the first FIA meeting, with substantial development and coordination of the NDN Testbed connecting the initial participating institutions, including network status reporting, state of (phase-one) OSPF routing, and testbed status pages. This two-day meeting packed in a wide range of collaborative discussions of architecture and implementation issues, including: topology and namespace structure and constraints; organizational structure and network management; routing and forwarding strategy; security issues such as attribution and privacy; early experiences with application development; evaluation and measurement; social and ethical values in technology design; and educational outreach (classes teaching NDN concepts). We also discussed how to dispel the misconception that NDN is simply collaborative web caching. (The caching is essential but the most revolutionary piece of this new communication model is retrieving data by names.)

Those familiar with the new emerging information-centric networking movement in the computer science research community will recognize NDN’s fundamental theme: replace the endpoint (identified by an IP address) as the fundamental anchor of the communications architecture with the data (identified by a name). To communicate in NDN, users post named interest(s) that propagate toward where the data resides (now relying on conventional routing protocols for the underlying routing fabric but eventually hopefully using previously developed revolutionary greedy routing mechanisms) and receives, from cryptographically vetted publishers, signed object(s) matching the requests. Conceptually simple, with many collateral benefits offered by the minimization of unnecessary layers. The application is much closer to the network. Mobility is inherent, since the notion of location has been removed as an architectural anchor.

While at least a dozen papers have resulted from this project thus far, even more tangible progress has occurred on the development and experimental deployment side. A key strength of this project (as mentioned previously) is a deployment path via a testbed overlay on the current Internet. Beichuan Zhang and Lan Wang have coordinated an OSPFN implementation that distributes name prefixes in OSPF and ccnd, and a ccnx-dhcp to help local bootstrapping, which will eventually include configuring default routes, local topology and hub discovery. Applications are already running on the NDN testbed including audio, video, and multi-user chat, which are being used by weekly project coordination calls; additional performance-related testing has been conducted using supercharged PlanetLab nodes.

In parallel, different teams are pursuing the various threads of research promised for the NSF project. Patrick Crowley is leading the investigation of how fast we can get NDN nodes to forward packets, and building traffic generators to evaluate and inform the protocol design. The security research team will present their first preliminary analysis of privacy, anonymization, and signature efficiency in NDN at this month’s NDSS conference. Edmund Yeh is creating a stochastic control and optimization framework to to formally (analytically) evaluate network performance, as well as coupling theoretical and experimental evaluation of joint forwarding and caching algorithms.

One of the next big R&D challenges is effective measurement techniques, not only for network management and performance evaluation — (“This node is being flooded with interests!”) — but also to support new types of network routing and application development and debugging (“Why is my application not getting the data?”).

We still need to study the impact of topology structure on network operations and management as we expand the set of external participants experimenting with the current platform and applications. We also still need core management functions such as methods to identify misbehaving nodes/apps, tools for debugging, log analysis, and traffic flow, the equivalents of chargen, traceroute, mechanisms for discovering one’s own local globally routable namespace (NDN prefix discovery) and other routing and institutional key information when joining a new network.

And of course, the eye of the volcano: the data namespace that NDN utlizes, including policy-relevant constraints that might determine what information should be exposed by the namespace structure. Because NDN object names may convey topological as well as content information, network elements could present treasures of performance, topology, and usage data that we can only dream about in the current architecture. But unlike today’s Internet, which convolves topological and organizational (peering) structure with the Autonomous System abstraction, the NDN architecture distinguishes these functions: signatures frame organizational/peer structure, while names frame the topological structure. There are obvious and not-so-obvious implications for privacy and attribution of communications, and we devoted an entire session to discussing social values that guide design decisions, with attorney Paul Ohm promising to help us assess the strength and form of expected tussles should an NDN architecture gain deployment traction.

Colorado State (home of PIs Dan Massey and Christos Papadopoulos) did a fantastic job of hosting the meeting, including a poster session and reception the evening of the first day. Several posters described undergraduate projects in Christos’ recent undergrad class on on NDN networking: running a traditional (modified) IP web traffic generator over the NDN testbed; repeating (and confirming) the 2009 CoNEXT paper experiment on PlanetLab); and a content caching study at CSU’s border router (estimating how much content is static (about half by requests) vs dynamic, and redundant request patterns). The second day included lots of discussion of what applications and supporting tools we should pursue next: including a graphical name space browser; graphical PIT viewer; a serverless Twitter-like application with scope control over message distribution; and a distributed, topic-based discussion board application to facilitate collaboration.

Toward the end of the meeting we discussed NSF’s request for thoughts about next steps after the FIA program currently funding this work (now half-way through its three-year budget). There are tremendous opportunities for synergy with other NSF-funded information science communities such as the Cyber-Physical Systems or the DataNets programs, to experimental deployment in production science settings such as the Open Science Grid (OSG), a national distributed computing grid for data-intensive research. Perhaps most exciting is the potential opportunity that Kevin Thompson (of NSF’s Office of Cyberinfrastructure) described at Internet2’s last Joint Techs meeting: in response to recently commissioned strategic advice, NSF wants to leverage successful R&D investments by transitioning them into campus environments on a broad scale, i.e., with a dedicated program. Since the NDN architecture was designed to solve many of the problems now being faced by campus networks (as well as the rest of the world), I’m optimistic that we could someday see an NDN-NSFNET. Lots of known unknowns and unknown unknowns along that path, but what an exciting path!

[Thanks to our lead PI Lixia Zhang of UCLA for help with this entry.]

Leave a Reply