Netos
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peer-to-peer online netflix (lovefilm)
Contact: Jon Crowcroft
Net2netflix (name subject to change)
Discussion document
v0
Solution has 2 parts
- delivery network:
The plan is to use an off-the-shelf structured p2p solution. Siddhu
is looking at different approaches, bittorrent, vidtorrent, zigzag for
delivery tree, etc. and evaluating the pros and cons of each one. Initial
report to be discussed around the end of September or so.
- superpeer overlay:
where most of our “new stuff” will come in to play, allowing
- the deployment (push
model) of superpeers on chosen xenoservers
- the selection of
“movie lists” by clients
- admission control
based on available resources, movies, and the probability of meeting
the delivery guarantee for a given movie list
- recommendations
of alternative movies etc
- prediction of delivery
time based on available copies of each move in the list and the estimated
bandwidth to/from the nodes
- management and monitoring
of downloads, including the superpeer “stepping in” when it looks
like a guarantee will not be met
The operation of the system
could be summarised as follows:
- a client contacts
the closest (or a close enough) superpeer, providing a list of movies
he or she wishes to view in the next few days
- the superpeer looks
in its own cache of movies as well as in the peers around it, to see
which movies (and how many copies of each one) are available in the
client’s vicinity
- the superpeer combines
its own statistics with client-side measurements (?) to come up with
a prediction in terms of the probability of a successful download within
a given time for the first few movies in the list, based on
- availability of
movie copies in the superpeer’s vicinity
- availability of
the movie in the superpeer’s cache
- bandwidth availability
between the client and the peers that hold the movie
- bandwidth availability
between the superpeer and the client
- ?
- based on the feasibility
of transmitting one of the selected movies to the client in the
required time, and a “probability threshold”, the superpeer’s
admission control system accepts or denies the client movie list request
- the superpeer monitors
all downloads, and if a download looks like it is not going to meet
the delivery guarantee (in terms of time) it steps in, allowing the
movie to be downloaded directly from its own cache (at a relatively
predictable and stable throughput). This costs resources to the superpeer
and is a “fallback” plan.
could use planetlab for
a start – latency and throughput very stable
eric: there is a good chance we can do fairly ok
challenge
4: work around firewalls?
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