Transcript 2008 - CLA
Campus da FEUP Rua Dr. Roberto Frias, 378 4200 - 465 Porto Portugal T +351 222 094 000 F +351 222 094 050 [email protected] www.inescporto.pt Communication Networks for Critical Infrastructures - topics under research at INESC Porto Manuel Ricardo DEEC, Faculdade de Engenharia, Universidade do Porto [email protected] © 2009 Telecommunications and Multimedia Unit 1 Outline • What is it? “Sistemas ciber-físicos para inteligência ambiente: redes de sensores em infra-estruturas criticas“ • Related research topics @ INESC Porto © 2008 Telecommunications and Multimedia Unit 2 Critical infrastructure • Critical infrastructure – term used by governments to describe assets essential for functioning of society /economy • Infrastructures commonly associated with the term – electricity, gas, oil – telecommunications – water – agriculture, food – public health – transportation – financial services – security services © 2008 Telecommunications and Multimedia Unit 3 Ambient Intelligence • Embedding intelligence in everyday objects • Object gains the ability to – Gather information from its environment possibly react by adapting its function – Process information – Exchange information with neighbour objects or Internet © 2008 Telecommunications and Multimedia Unit 4 The Intelligent Object • Computers are becoming small • Common object becoming also a computer © 2008 Telecommunications and Multimedia Unit 5 Ambient Intelligence in Critical Infrastructures • Objects of critical infrastructures will become computers • New objects (criticality related) will be added to infrastructure • As a result, critical infrastructures expected to become efficient , reliable, secure © 2008 Telecommunications and Multimedia Unit 6 The Challenges of Interconnecting Objects • Thousands of computing-objects to be interconnected through wireless, auto-configurable, high-bitrate, secure networks • Research-topics@INESCPorto – Scalable auto-configurable networks – Intermittent connectivity / mobility – Enabling high bitrates – Network congestion control – Information aware networks – Moving PAN – Secure Networks © 2008 Telecommunications and Multimedia Unit 7 Scalable and Auto-Configurable Networks • Plug & play network – Ethernet like network – Big network = big LAN Node • Some network services – DHCP, ARP, IPv6 link local – Routing protocols ARP REQUEST – Generate broacast traffic Network becomes congested Node Shortest Path Link Eliminated by STP • Research@INESCPorto – Re-design network services to avoid broadcast traffic Using prune + data suppression/compression techniques – Design large virtual Ethernet networks over existing technologies © 2008 Telecommunications and Multimedia Unit 8 Intermittent Connectivity and Mobility in Large Networks • Global frequent routing update leads to excessive overhead • Ad-hoc routing protocols inadequate for large networks • Research@INESCPorto – New routing techniques for wireless and mobile networks – New/lost links reported only to relevant nodes © 2008 Telecommunications and Multimedia Unit 9 Enabling High Bitrates - Directional Antenna • Bitrate of a wireless link depends on Bandwidth, Rx power, SINR • Directional antenna enables – More received power /longer links – Less interference – More links • Research@INESCPorto – What criteria use to form beams? – How to combine • on demand-links and routing techniques? • beams with multichannel? © 2008 Telecommunications and Multimedia Unit 10 Enabling High Bitrates – Avoiding Hidden Nodes • Wireless networks rely on CSMA/CA shared access mechanisms • CSMA/CA performance depends on – Number of nodes – Number of hidden nodes • Research@INESCPorto Network topology control • reduce number of hidden nodes for less collisions • dynamic selection of radio channels © 2008 Telecommunications and Multimedia Unit 11 Network Congestion Control • Current congestion control mechanisms – inadequate for variable bitrate media shared media / variable bitrate links – unfair for real-time /short traffic flows • Research@INESCPorto – Use of explicit control techniques network nodes control the sources rate – Feedback signal considers nodes congestion and energy – Management of traffic priorities © 2008 Telecommunications and Multimedia Unit 12 Information Aware Networks • Application and physical networks are different e.g. P2P application over ad-hoc networks • Research@INESCPorto – Define network paths based on • link quality, node energy • type of information – Network topology constrained by application © 2008 Telecommunications and Multimedia Unit 13 Moving Personal Area Networks PAN • Multi-technology PAN audio files photos Intra/extra PAN connectivity Bluetooth UWB docs Wi-Fi Internet • Research@INESC Porto – PoA selected based on user-defined policies – Centralized single tree routing UMTS videos UWB – Adaptive IP autoconfiguration docs Bluetooth BAN © 2008 Telecommunications and Multimedia Unit 14 Secure Networks CA 1 • Networks need to be secure CA 2.1 CA 2.2 Security between any pair of nodes N 2.1.2 N 2.1.1 • Research@INESCPorto Network 2.2 Cert 2.2 N2.2.1 ({id2.2.1 , pk2.2.1 , ta, tb}pkCA2.2) – Hierarchical distributed PKI Network 2.1 N 2.2.1 N 2.1.3 • Ephemeral certificates Auth2.2.1({id2.2.1, pk2.2.1, ta, tb}pkCA2.2) • Used to authenticate a node • Short public keys low processing power • No revocation lists support of intermittent connectivity – Secure group communications • Authentication by certificates Receiver • Short symmetric keys • Key distribution using multicast techniques © 2008 Telecommunications and Multimedia Unit 15