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Endless Arguments in Systems Design
Jon Crowcroft, University of Cambridge
Currently IMDEA Networks.Jon.Crowcroft@cl.cam.ac.uk
http://www.cl.cam.ac.uk/~jac22
GENI – Global Environment for Network Innovation
US NSF/Extra Money Calls for Intl participation Planetlab++ (Intel/300 site)
FIND – Future Internet Design
NSF long term research in NeTS programme
40+ Projects Quite mixed bag [EU Trilogy project (which UC3M and
UCL and others are in) did analysis of them]
email WWW phone...
SMTP HTTP RTP...
TCP UDP…
IP
ethernet PPP…
CSMA async sonet...
copper fiber radio...
The Internet Protocol Hourglass(Deering)
email WWW phone...
SMTP HTTP RTP...
TCP UDP…
IP + mcast
+ QoS +...
ethernet PPP…
CSMA async sonet...
copper fiber radio...
Putting on Weight
• requires more functionality from underlying networks
email WWW phone...
SMTP HTTP RTP...
TCP UDP…
IP4 IP6
ethernet PPP…
CSMA async sonet...
copper fiber radio...
Mid-Life Crisis
• doubles number of service interfaces
• requires changes above & below
• major interoper-ability issues
Or is GENI losing its bottle?
Network Innovation is a Hot Topic Internet problems abound 2/3G problems abound Convergence driving incremental Critical Infrastrure driving radical Many US GENI/FIND +EU +Asia projects There appear to be some ok ideas But also some wrong headedness
This is a case study on wrong headedness
Incremental from Convergence
SCTP (PSTN signaling transport on IP) SIP&NAT traversal&VOIP in general IPTV (Multicast & P2P) BGP fast Convergence Traffic Engineering (whether OSPF TE
or RSVP or MPLS based) Neutrality fights
Long Term
IP Service Best Effort So DDoS not meaningul Not helpful – need architectural change
Fundamentally, Mobile, Multicast, Multihome Possibly Multiprotocol (esp. Control Plane) DoS Resistence, built in Possibly different economic/charging models
Need shift in model Maybe not a stack anymore Certainly not IP ++ ++ ++
i.e. not just IPv6 with current IPv4 knobs and warts
Two wrongs that don’t make a right(#)
Virtualisation of Networks Next Generation Wireless Data Driven Networks
(#) Two parts of FIND/GENI work in USthat I feel they are doing wrong and
we are doing right + one thing I think the US and EU are both doing right.
Veni, Vidi, Vici, but not Vini?
Virtualisation is not about VPNs(*) Hierarchical Hard Multiplexing won’t scale VPNs are an ok idea in the Enterprise Its too slow to reconfigure on outages Its bad for resource allocation in wireless C.f. hard spectrum allocation C.f. hard channel allocation
* Not just VPI/VCI (for those who recall B-ISDN!)
Virtualisation of Control not Data
In Xen/Xorp work: key is about dynamics and isolation of
functionality, not fwding performance Need to deploy disjoint service ctl
True, vpn style IP fwding is useful too But no unified way of doing this on
wireless Or on multipath Or for netcoded data Or swarms…
Next Gen Wireless
Cooperative Diversity in all things Antennae, coding, routing, power, spectrum,
“channels” Behavioural constraints enforced (aside: F# smart phone:-)
Infrastructure still there for services, e.g. To provide radio map (with memory) Security/Identity/Location Assistence Maybe even payment
Control plane for virtual wireless communities
Data Driven, Declarative,
We’ve seen 1-1, 1-n, n-1 comms patterns Now we’re seeing 0-n and n-0 US loves to re-invent(+) - but in fact Pub/sub;event/notify isn’t all there is:
Think swarm Think anysource multicast
Exaflood is no big deal when decentralised…properly
Think exploding google (aside: haggle:)(+) architecture is not just creative
children’s stories.
Virtual, Wireless, Declarative Data?
We’d all like to get rid of wires (on the other hand, we’d probably all
like to get rid of batteries too:) So high capacity applications should
be user contributed content too What is the control plane for these to
co-exist with each other? C.f. nano-datacenters and haggle,
unified
0wning half a PC (or hub or STB)
Significant fraction of internet access via Home Hubs
Significant fraction of wireless acces via smart phones
Home hub as PVR, smart phone as PC Lots of storage + faces 3 ways
Faces “wide area”; faces home Faces neighbours… … … Changes economic relationships
completely
Provider coexist w/ virtual providers
If provider wants to scale net, Run P2P for CDN on home hub And do end run on data centers Let home user also run P2P CDN Let wireless user also run community and ad
hoc mesh Virtualise STB + Handsets With suitable declarative(pub) Ctl Plane
Paradigm shift now enabled Revenue model from services not bitpipes
Way forward?
Devil is in detail Remove separation of end +
intermediate system All systems may have storage Must restore flow, congestion and
reliability control functions to “network” But do not need them “point-to-point”
So they are going to look very different Everyone is a DTN custodian
& there is no “network”
Summary/Conclusions
GENI is ok for next generation core IP Need more fundamental changes if we
address high speed wireless everywhere Especially since application paradigm
already shifting Europe well placed to contribute:
both wireless and application architecture, which in turn contribute to immediate and long
term network architecture better than incremental core work….
not that that is a bad thing either!
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