EngEdu Video Write-up: “A New Way to Look at Networking”

“A New Way to Look at Networking” by Van Jacobson

This is great video on the history of voice and TCP/IP networking. Van Jacobson shows the telephone network solved the problems of its day and framed out thinking. He then shows how TCP/IP packet switching solved more problems and framed our thinking again. He then suggests we should be thinking about a data centric view of networking, and that our problems warrant another generation of networking. Then the talk falls down.

[00:00]

Van Jacobson’s resume is impressive: he solved many of the Internet congestion problems, worked on the MBONE, wrote early whiteboard software, and generally knows his packets.

[07:00] History of Telecommunications, the Phone System

The telephone system, Ma Bell, emphasized wires and connecting wires to each other. A telephone number is just a program for which wires to connect to build a path, committing each segment before the next segment is parsed. Reliability was enforced by a centralized architecture with extremely reliable components. The pipes were smart because the end points were dumb. This view of the world really did work for phone conversations and got wires pulled everywhere.

[17:20] History of Telecommunications, the Packet Generation

In about 1964, Paul Baran and Don Davies publiched a paper on breaking data into small packets and passing them from link to link in a communications system that could be less than fully interconnected. The paper was denounced by all, and the ARPANet was built anyway. At first, this looked like an inefficient way to use the wires already in place courtesy of the telephone generation. With practice, it proved useful.

[24:53] CateNet and TCP/IP (1971 paper, 1977 demo) improve the Packet Generation

ARPANet worked, and by the early 1970’s there were a dozen incompatible packet switched networks. Vint Cerf and Bob ? from Stanford took the viewpoint that only the endpoints mattered, not the topology of the networks. A common encapsulation and addressing scheme suffice to concatenate networks using the encapsulation and addressing only at thenetwork edges. They demonstrated moving bits from packet radio, through satelites, telephone lines, and other networks. Bits were bits, and reliability *increases* exponentially with system size. No path set-ups, no scheduling issues; just an address.

[31:10] The Success Catastrophe of TCP/IP Packet Generation.

The TCP/IP data model works for conversations between computers and has made a world rich in devices, connections, and information. The challenges of firewalls, VPNs, ad-hoc synchronization, and NATs are symptoms of the success and of changing problems. The Internet is binary; you are connected with a global address that lasts in the minutes or hours or you are not. We now face problems with many machines per devices, and those devices are moving between networks quickly.

[38:25] The Data Generation; a coming generation based on finding and replicating data.

Almost all requests today are for named blocks of data. Downstream switches are often processing many copies of the same video stream. Radio based networks target individual receivers by broadcasting the same data to all and having most ignore it. The TCP/IP protocols are based on one-to-one conversations between computers; we should research fetching and caching data.

New data chunks would include validation hashes, providence hashes, sequence information, and a degree of permanance. Every cachable device would be a vehicle for data.

[44:53] The descent into unorganized ideas.

That said, the talk descends into unorganized ideas. There is a short thought demonstration of fetching the NYTimes headline with validation and providence hashes. There are complaints about lack of multicasting; good things to say about BitTorrent and SnakeBite; ideas of moving QoS to the endpoints and progating back to the core; requests for fast set up times and for alternatives to DSL; wishes to have cached repositories in the local area; instant PKI and webs of trust beating certificate authorities; and a host of complaints about our current infrastructure.

Most of these ideas about data centric networking are not well thought out, which may the point of the talk.