Unit 3 - Advanced Internet Architectures

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Unit 3 - Advanced Internet Architectures
Carlos Borrego Iglesias,Sergi Robles
Carlos.Borrego@uab.cat,Sergi.Robles@uab.cat
Departament d’Enginyeria de la Informació i de les Comunicacions
Universitat Autònoma de Barcelona
Tecnologies avançades d’Internet,curs 2012/13
p2p Wireless Networks Delay And Disruption Tolerant Networks Anonymous Networks
Contents
1
A peer-to-peer architecture
2
Wireless Networks
3
Delay And Disruption Tolerant Networks
4
Anonymous Networks
– Carlos Borrego Iglesias,Sergi Robles
Unit 3 2/21
p2p Wireless Networks Delay And Disruption Tolerant Networks Anonymous Networks
Architecture Applications
Contents
1
A peer-to-peer architecture
Architecture
Applications
2
Wireless Networks
3
Delay And Disruption Tolerant Networks
4
Anonymous Networks
– Carlos Borrego Iglesias,Sergi Robles
Unit 3 3/21
p2p Wireless Networks Delay And Disruption Tolerant Networks Anonymous Networks
Architecture Applications
Peer-to-peer Architecture
Definition:A peer-to-peer (abbreviated to P2P) computer network is one in
which each computer in the network can act as a client or server for the other
computers in the network (peers).
Types:
Pure peer-to-peer systems:The entire network consists solely of
equipotent peers.
Centralized peer-to-peer systems:A central server is used for indexing
functions and to bootstrap the entire system.
Hybrid peer-to-peer systems:Allow such infrastructure nodes to exist,
often called supernodes.
– Carlos Borrego Iglesias,Sergi Robles
Unit 3 4/21
p2p Wireless Networks Delay And Disruption Tolerant Networks Anonymous Networks
Architecture Applications
Distributed hash table
Definition:decentralized distributed hash table
system.
Transparency:Any participating node can efficiently
retrieve the value associated with a given key.
Good scalability:A change in the set of participants
causes a minimal amount of disruption.
– Carlos Borrego Iglesias,Sergi Robles
Unit 3 5/21
p2p Wireless Networks Delay And Disruption Tolerant Networks Anonymous Networks
Architecture Applications
Contents
1
A peer-to-peer architecture
Architecture
Applications
2
Wireless Networks
3
Delay And Disruption Tolerant Networks
4
Anonymous Networks
– Carlos Borrego Iglesias,Sergi Robles
Unit 3 6/21
p2p Wireless Networks Delay And Disruption Tolerant Networks Anonymous Networks
Architecture Applications
File sharing networks
Definition:Allows users to download media files using a P2P
software client that searches for other connected computers.
A user creates a small torrent descriptor.They then make the
file itself available through a BitTorrent node acting as a seed.
Those with the torrent descriptor file can give it to their own
BitTorrent nodes which,acting as peers or leechers,download
it by connecting to the seed and/or other peers.
The file being distributed is divided into segments called pieces.
Examples:gnutella,bittorrent,G2 and the eDonkey
– Carlos Borrego Iglesias,Sergi Robles
Unit 3 7/21
p2p Wireless Networks Delay And Disruption Tolerant Networks Anonymous Networks
Architecture Applications
Other Applications
Software publication and distribution:Example:Linux,several games.
Streaming media:P2PTV and PDTP.Applications include TVUPlayer,
Joost,CoolStreaming,Cybersky-TV,PPLive,LiveStation,Giraffic and
Didiom.
Spotify:Peer-to-peer network along with streaming servers to stream
music to its desktop music player.
Bitcoin:Peer-to-peer based digital currency.
WWWSearch:For example:YaCy,a free distributed search engine,built
on principles of peer-to-peer networks.
Skype:one of the most widely used internet phone applications is using
P2P technology.
– Carlos Borrego Iglesias,Sergi Robles
Unit 3 8/21
p2p Wireless Networks Delay And Disruption Tolerant Networks Anonymous Networks
Ad Hoc Networks Mobile Ad Hoc Networks
Contents
1
A peer-to-peer architecture
2
Wireless Networks
Ad Hoc Networks
Mobile Ad Hoc Networks
3
Delay And Disruption Tolerant Networks
4
Anonymous Networks
– Carlos Borrego Iglesias,Sergi Robles
Unit 3 9/21
p2p Wireless Networks Delay And Disruption Tolerant Networks Anonymous Networks
Ad Hoc Networks Mobile Ad Hoc Networks
Ad Hoc Networks
Definition:A wireless ad hoc network is a decentralized type of
wireless network.It does not rely on a preexisting infrastructure.
Instead,each node participates in routing by forwarding data for
other nodes.
– Carlos Borrego Iglesias,Sergi Robles
Unit 3 10/21
p2p Wireless Networks Delay And Disruption Tolerant Networks Anonymous Networks
Ad Hoc Networks Mobile Ad Hoc Networks
Addressing
Zero configuration networking Host/routers may
automatically configure an interface with an IPv4 address
within the 169.254/16 prefix that is valid for communication
with other devices connected to the same physical (or
logical) link.
The address selection algorithm is based on computing a
hash on the interface’s MAC address.(RFC 3927).
The multicast Domain Name SystemWhen an mDNS
client needs to resolve a host name,it broadcasts a query
message that asks the host having that name to identify
itself.That target machine then multicasts a message that
includes its IP address.All machines in that subnet use
that information to update their mDNS caches.RFC 6762.
– Carlos Borrego Iglesias,Sergi Robles
Unit 3 11/21
p2p Wireless Networks Delay And Disruption Tolerant Networks Anonymous Networks
Ad Hoc Networks Mobile Ad Hoc Networks
Routing
Pro-active:Maintains fresh lists of destinations and their routes
by periodically distributing routing tables throughout the network.
Examples:B.A.T.M.A.N.,Optimized Link State Routing Protocol
(RFC 3626).
Reactive:Finds a route on demand by flooding the network with
Route Request packets.Examples:Ad hoc On-demand
Distance Vector(AODV) (RFC 3561),Dynamic Source Routing
(RFC 4728).
Hybrid (both pro-active and reactive):Combines the
advantages of proactive and of reactive routing.The routing is
initially established with some proactively prospected routes and
then serves the demand from additionally activated nodes
through reactive flooding.The choice for one or the other
method requires predetermination for typical cases.Examples:
ZRP (Zone Routing Protocol).
– Carlos Borrego Iglesias,Sergi Robles
Unit 3 12/21
p2p Wireless Networks Delay And Disruption Tolerant Networks Anonymous Networks
Ad Hoc Networks Mobile Ad Hoc Networks
Contents
1
A peer-to-peer architecture
2
Wireless Networks
Ad Hoc Networks
Mobile Ad Hoc Networks
3
Delay And Disruption Tolerant Networks
4
Anonymous Networks
– Carlos Borrego Iglesias,Sergi Robles
Unit 3 13/21
p2p Wireless Networks Delay And Disruption Tolerant Networks Anonymous Networks
Ad Hoc Networks Mobile Ad Hoc Networks
Mobile Ad Hoc Networks (MANETs)
Definition:A mobile ad hoc network (MANET) is a
self-configuring infrastructureless network of mobile devices
connected by wireless.
Each device in a MANET is free to move independently in any
direction,and will therefore change its links to other devices
frequently.Each must forward traffic unrelated to its own use,
and therefore be a router.
– Carlos Borrego Iglesias,Sergi Robles
Unit 3 14/21
p2p Wireless Networks Delay And Disruption Tolerant Networks Anonymous Networks
Ad Hoc Networks Mobile Ad Hoc Networks
Classification
Vehicular Ad hoc Networks (VANETs):Used for
communication among vehicles and between vehicles and
roadside equipment
Internet based mobile ad hoc networks (iMANET):Ad
hoc networks that link mobile nodes and fixed
Internet-gateway nodes.In such type of networks normal
adhoc routing algorithms don’t apply directly.
– Carlos Borrego Iglesias,Sergi Robles
Unit 3 15/21
p2p Wireless Networks Delay And Disruption Tolerant Networks Anonymous Networks
Mobile Ad Hoc Networks (MANETs)
Definition:Delay-tolerant networking (DTN) is an approach to
computer network architecture that seeks to address the
technical issues in heterogeneous networks that may lack
continuous network connectivity.
Follow the Store-carry-and-forward paradigm:Information is
sent to an intermediate station where it is kept and sent at a later
time to the final destination or to another intermediate station.
– Carlos Borrego Iglesias,Sergi Robles
Unit 3 16/21
p2p Wireless Networks Delay And Disruption Tolerant Networks Anonymous Networks
Delay and Disruption Tolerant Networks (DTN)
Research:DTN,opportunistic networks,challenged
networks,partitioned networks...
Characteristics:Intermittent connectivity,
asymmetric bandwidths,long and variable latency,
ambiguous mobility patterns...
New applications made possible
Applications:WSN,space applications,emergency
scenarios,medical application in developing
countries...
– Carlos Borrego Iglesias,Sergi Robles
Unit 3 17/21
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Delay and Disruption Tolerant Networking Architecture
RFC4838:Describes an architecture for DTN using
Store-carry-and-forward.
RFC5050:Describes the end-to-end protocol,block
formats,an abstract service description for the
exchange of messages (bundles) in DTN
– Carlos Borrego Iglesias,Sergi Robles
Unit 3 18/21
p2p Wireless Networks Delay And Disruption Tolerant Networks Anonymous Networks
Routing in Delay and Disruption Tolerant Networks
Definition:next hop decision process
Complex decision due to DTN characteristics
Classification:based on the number of copies,geographical,
probabilistic,epidemic...
Routing code is located in the intermediate nodes
Lack of proposals for scenarios with different applications with different
routing needs
– Carlos Borrego Iglesias,Sergi Robles
Unit 3 19/21
p2p Wireless Networks Delay And Disruption Tolerant Networks Anonymous Networks
TOR
Contents
1
A peer-to-peer architecture
2
Wireless Networks
3
Delay And Disruption Tolerant Networks
4
Anonymous Networks
TOR
– Carlos Borrego Iglesias,Sergi Robles
Unit 3 20/21
p2p Wireless Networks Delay And Disruption Tolerant Networks Anonymous Networks
TOR
TOR,the Onion Router
Definition:System intended to enable online
anonymity.
Onion Routing refers to the layered nature of the
encryption service:The original data are encrypted
and re-encrypted multiple times,then sent through
successive Tor relays,each one of which decrypts a
l
.
layer"of encryption before passing the data on to the
next relay and,ultimately,its destination.
– Carlos Borrego Iglesias,Sergi Robles
Unit 3 21/21