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Y-Comm: A new architecture for heterogeneous networking Glenford Mapp Principal Lecturer, Middlesex University & Visiting Research Fellow Computer Lab, University of Cambridge Outline • • • • • • • • Motivation – defining the problem Our approach – looking at a solution Y-Comm – a new architecture The Peripheral Framework The Core Framework Security in Y-Comm Research Collaboration Questions Network Evolution • The proliferation of wireless systems at the edge of the Internet and the use of fast switching in the core. • Core of the network – Super-fast backbone (optical switching, etc) – Fast access networks (MPLS, ATM) • Peripheral Wireless Networks – Errors due to fading, etc; not just congestion – Handover Handover is a serious operation • Handover – Requires co-operation between the Mobile Node and the Network – A source of performance degradation • Needs to be carefully handled to be successful • Handover Types – Horizontal handover – studied extensively – Vertical Handover – needs to be investigated in order to support heterogeneous networking Key Components of Vertical Handover • Handover mechanisms • How to do vertical handover with minimal disruption • Policy management • Deciding when and where to do a vertical handover • Input triggers, states and events • How to get the data the system needs to make a decision on whether to do a handover Cambridge Wireless Testbed • Built in 2003 to study vertical handover – By Leo Patanapongpibul and Pablo Vidales • Used an experimental 3G/GPRS network developed by Vodafone • Used MIPv6 – connected to 6Bone • 2 802.11b networks and an IPv6 wired network • Various end devices – Fixed machines, laptops and iPAQs Equipment and Goals • Client-based solution for horizontal handovers • MIPv6 performance during vertical handovers • Improvements to vertical handover latency • Policy-based solution to provide mobility support • Policy-based solution to support multiple interfaces • QoS-based vertical mobility • Context-aware algorithms Mobile Node Home Agent Access Router to live Vodafone GPRS network Correspondent Node Other MNs Cambridge Wireless Testbed Testbed Monitor : Key Publications : available from http://www.cl.cam.ac.uk/Research/DTG/publications • L. Patanapongpibul, G .Mapp, A. Hopper, An End System Approach to Mobility Management for 4G Networks and its Application to ThinClient Computing, ACM SIGMOBILE Mobile Computing and Communications Review, ACM July 2006 • • • • P. Vidales, J. Baliosian, J. Serrat, G. Mapp, F. Stajano, A. Hopper, Autonomic Systems for Mobility Support in 4G Networks. Journal on Selected Areas in Communications (J-SAC), Special Issue in Autonomic Communications (4th Quarter), December 2005. D.Cottingham and P. Vidales, Is Latency the Real Enemy of Next Generation Networks, First International Workshop on Convergence of Heterogeneous Networks, July 2005 P. Vidales, R. Chakravorty, C. Policroniades, PROTON: A Policybased Solution for Future 4G devices. 5th. IEEE International Workshop on Policies for Distributed Systems and Networks (IEEE POLICY 2004), June 2004 L. B. Patanapongpibul, G. Mapp, A Client-based Handoff Mechanism for Mobile IPv6 Wireless Networks. 8th IEEE Symposium on Computers and Communications (ISCC), IEEE Computer Society Press, June 2003. A Complete System for Heterogeneous Networking • In order to build a complete system that – Does seamless vertical handover – Is extensible – seamlessly adds new technology – Is easy to develop new applications • Requires a lot of work – Can’t do this from scratch – Need to also look at what other people are doing • Ambient networks, etc • IEEE 802.21, etc A New Framework is needed • Why? – Need to consider a lot of issues • Issues not covered by present reference models such as the OSI model – A way to think about building a complete system – Bring together different research efforts The OSI Model APPLICATION LAYER APPLICATION LAYER PRESENTATION LAYER PRESENTATION LAYER SESSION LAYER SESSION LAYER TRANSPORT LAYER TRANSPORT LAYER NETWORK LAYER NETWORK LAYER NETWORK LAYER DATA LINK LAYER DATA LINK LAYER DATA LINK LAYER PHYSICAL LAYER PHYSICAL LAYER PHYSICAL LAYER ENDPOINT NETWORK ENDPOINT Specifying the New Framework • Layered approach of the OSI model – Encase functionality in terms of layers – Can give a good hierarchical but modular model – We know that the layered approach has its problems • This is a reference not an implementation specification – so it is possible to squash layers together when implementing a real system • Need to be flexible We Need Two Not One! • A framework for the Peripheral network – Represented by software running on the mobile node, supports: • Applications, QoS, Vertical Handover, support for several interfaces • A framework for the Core network – Represented by software running in the core network, supports • Programmable infrastructure, network management, QoS, Service Platform The Y-Comm Framework PERIPHERAL NETWORK APPLICATION ENVIRONMENTS QOS LAYER END SYSTEM TRANSPORT POLICY MANAGEMENT VERTICAL HANDOVER NETWORK ABSTRACTION (MOBILE NODE) HARDWARE PLATFORM (MOBILE NODE) CORE NETWORK SERVICE PLATFORM NETWORK QOS LAYER CORE TRANSPORT NETWORK MANAGEMENT (RE)CONFIGURATION LAYER NETWORK ABSTRACTION (BASE STATION) HARDWARE PLATFORM (BASE STATION) The Peripheral Framework APPLICATION ENVIRONMENTS LAYER QOS LAYER END TRANSPORT SYSTEM POLICY MANAGEMENT LAYER VERTICAL HANDOVER LAYER NETWORK ABSTRACTION LAYER HARDWARE PLATFORM LAYER Layer 1: Hardware Platform Layer • Hardware Platform Layer – Defines the physical requirements for a particular wired or wireless technology – Expanded physical layer • Includes electromagnetic spectrum • Modulation and channel reservation algorithms – Incompatibility issues • Two technologies may be incompatible and cannot be used simultaneously Hardware Platform Layer Represented as Vertical Components 3G WLAN 802.11 WiMax 802.16 UltraWideBand But all this is about to change! • Need to make more efficient use of the electromagnetic spectrum • Cognitive Radio – A radio that is aware of and can sense its environment, learn from its environment, and adjust its operation according to some objective function Cognitive Radio (CR) • Technology – Software Defined Radio (SDR) • Wide spectrum receiver • Do the processing in real-time – Intelligent Signal Processing (ISP) • Allows it to detect interference and move to another part of the spectrum – Ideal cognitive Radio – Mitola Radio > 2030 • Mitola radio uses CR as the physical layer of a communications model • That’s why CR is part of Y-Comm Cognitive Radio SPECTRUM MANAGEMENT 3G WLAN WiMax UltrawideBand INTELLIGENT SIGNAL PROCESSING SOFTWARE DEFINED RADIO WIDE SPECTRUM REECIVER Layer 2: Network Abstraction layer • Network abstraction Layer – An abstraction that allows us to define, control and manage any wireless network on a mobile host – Key issues: data path functions; data formats (Link-layer), turning features on and off – Need to generate L2 triggers when a new network is detected or when an old network is no longer detectable • Build on 802.21 802.21 Overview 802.21: Key Services Applications (VoIP/RTP) Link Layer Triggers Handover Connection Management State Change Handover Management Predictive Network Mobility Management ProtocolsInitiated IETF Policy Smart Triggers Handover Messages Information Service IEEE 802.21 802.21 MIH Function Handover Commands L2 Triggers and Events WLAN Network Information Available Networks Neighbor Maps Network Services Client Initiated Network Initiated Vertical Handovers Handover Messages Information Service Cellular WMAN Protocol and Device Hardware 802.21 uses multiple services to Optimize Vertical Handovers Layer 3: Vertical Handover Layer • Layers that define the mechanism for vertical handover. • Support for different types – Network-based – Client-based Client-Based Handover • More scalable for heterogeneous networks – Mobile node can monitor the status of all its network interfaces via the network abstraction layer – Can take into account other factors such as the state of TCP connections • Don’t want to do a handover during the start and termination of TCP connections Layer 4: Policy Management layer • Decides if, when and where vertical handover should occur. • Different types: – Reactive • Depends on L2 events that inform the mobile node when it is entering or leaving a network. – Proactive • The mobile node can know or estimate the network state at a given point before it arrives at that point Reactive Policy: PROTON HIGHER LAYERS Interface Information L2 Triggers INPUT/OUTPUT LAYER POLICY LAYER (PONDER) HANDOVER EXECUTION LAYER WLAN GPRS LAN Layer 4: Proactive Policies • Proactive Policy Management – The mobile node can know or estimate the network state at a given point before it arrives at that point – Proactive Policies allow us to maximize the use of available channels provided you know the amount of time a channel will be available. – That time is known as: • Time before vertical handover (TBVH) • Can significantly reduce packet loss during all vertical handovers Layer 4: Proactive policies • Proactive policies can themselves be divided into 2 types • Proactive knowledge-based systems – Knowledge of which local wireless networks are operating at a given location and their strengths at that point – We also need a system to maintain the integrity, accessibility and security of that data Proactive Policies • Knowledge-based approach • Gather a database of the field strengths for each network around Cambridge • Need to maintain the database and also know how the results might be affected by seasonal effects Knowledge-Based Policy Management (Cambridge) Proactive Policies – Modelling Approach (Middlesex) • Using a simple mathematical model • Define a radius at which handover should occur • Find out how much time I have before I hit that circle, given my velocity and direction • Calculate TBVH • Used simulation (OPNET) • Can be used in the real world as well as in simulation Predictive Mathematical Model for TBVH (Simple Case) Movement of MS under BBS coverage (upward vertical handoff) • Introduction of additional functionality to Base Station at network boundary (BBS). • Distance between MS and BBS derived from location co-ordinates or RSS dB 10 log( l ) • Estimated TBVH r 2 d 2 sin 2 x d cos x TBVH v BBS r d x z MS Simulation and Results TBVH simulation in OPNET Modeler: Layer 5: End User Transport System • Specifies how data is routed to individual hosts and transport protocols for error correction, reliability and Quality-of-Service requirements – Encompasses Layer 3 and Layer 4 in the OSI model • Different approaches – Keep the same protocols as in the core network – Keep TCP/IP, but modify TCP – Don’t modify TCP but try to get it to respond more quickly to network outages – Try a completely new protocol suite Layer 5: Continued • Keep TCP/IP Unmodified – Leads to sub-optimum performance. • TCP assumes packet loss is only due to congestion and goes into slow start. – Work on the Cambridge Testbed indicates to the slow adaptation rate of TCP after vertical handover is a cause for concern • Need to fit the TCP protocol engine with triggers Layer 5: Slow Adaptation of TCP After LAN->GPRS Handover Layer 5: Continued • Keep TCP/IP but modify TCP – I-TCP, M-TCP – TCP Extensions for Immediate Retransmissions (Internet Draft) • Don’t modify TCP but build mechanisms so that it could respond more quickly to media outages – Smart Link Layer (Scott and Mapp 2003) Layer 5: The case for a new transport Infrastructure • A new transport system could be more suited for wireless networking • Do all machines have to have an IP address to use the Internet? • No.. Look at Network Address Translation (NAT) • Translation is done between a private address and port to a global address and port at the NAT server Layer 5: Continued • A global IP address in the case of NAT is really being used as an endpoint in the core network • So we can use another network scheme in the peripheral network once we can specify how we map it to TCP/IP or UDP/IP in the core network Layer 5: Application Conformance • You don’t want to recompile all your applications for this new framework • Concept of a TCP protocol interface – Key idea is that TCP becomes an interface so that the TCP engine forms an overlay above the actual protocol running in the network. So the application thinks it’s running TCP/IP but there is another protocol “under the hood”. Layer 5: TCP as a Protocol Interface in Peripheral Networks but a real protocol in the Core Network APPLICATION APPLICATION Core Network TCP Overlay Local protocol Peripheral Network TCP Overlay TCP/IP Local protocol Core Network Peripheral Network Layer 6: QoS Layer • QoS is the most dynamically changing component in heterogeneous networking • Applications running on heterogeneous devices need support to handle this • Two Concepts of QoS – Downward QoS – Upward QoS Layer 6: Downward QoS • Mainly to support legacy applications • The application specifies a minimum QoS and the QoS layer does the mapping between the QoS that the application requires and the QoS that is currently available - but is dynamically changing Layer 6: Upward QoS • For applications that should adapt to changes in QoS, e.g. Multimedia services, etc – The QoS layer therefore signals the application using an event mechanism to indicate changes in the available QoS – Applications can specify routines that will be called when the events occur • Similar to the X Window System QoS Layer DOWNWARD QOS UPWARD QOS APPLICATION LAYER APPLICATION LAYER QOS LAYER QOS LAYER END TRANSPORT LAYER END TRANSPORT LAYER POLICY MANAGEMENT LAYER POLICY MANAGEMENT LAYER Layer 7: Application Environment Layer • Allows users to build applications using this framework • Keen on using the Toolkit approach which allows us to build different application environments for different situations – e.g. an application environment for highly mobile video applications, etc. Layer 7: Toolkit Approach Application Environment 1 High-Mobile, Multimedia Vehicular Applications FRAMEWORK OBJECTS PROACTIVE Handover Unreliable Transport Upward QoS Location Services (GPS) Reliable Transport REACTIVE Handover Downward QoS Application Environment 2 Touring Applications; Web access via cheap mobile phone The Y-Comm Framework Half-way there! Let’s stop for questions PERIPHERAL NETWORK APPLICATION ENVIRONMENTS QOS LAYER END SYSTEM TRANSPORT POLICY MANAGEMENT VERTICAL HANDOVER NETWORK ABSTRACTION (MOBILE NODE) HARDWARE PLATFORM (MOBILE NODE) CORE NETWORK SERVICE PLATFORM NETWORK QOS LAYER CORE TRANSPORT NETWORK MANAGEMENT (RE)CONFIGURATION LAYER NETWORK ABSTRACTION (BASE STATION) HARDWARE PLATFORM (BASE STATION) Do we really need the Core Framework? • Yes – To support the Peripheral networks you need to change • For client-based handover we need to have access to network resources – Need a more open architecture – But we also need an open architecture for other reasons Open Management Needed • More diversified networks needed – Present mobile networks are built on a national or international level: • just like the old state-owned telecom companies – such as BT • Difficult to really produce more tailored networks such as regional networks or city-wide networks – Spectrum management • Spectrum sold nationally to an operator who ran a service – Not interested in small or regional networks • Reversal in spectrum allocation – Now Ofcom is willing to allow more unlicensed bands RFEye from CRFS Cambridge Ofcom will be able to monitor The use of spectrum in real-time Used to be expensive but new technology from a company called CRFS will make these units cheap. RFEye Develop a database of spectrum use http://www.crfs.co.uk/product.html Open Management Needed • So the question is who is really making money from mobile systems at the moment?? • The answer: – Very few people • Vodafone, T-Mobile – Spent loads of money on spectrum, they need to grow bigger to recoup the money spent • These companies are highly vertical institutions – Same company does hardware, manage the network and also run or tailor most applications Open Management Needed • More niche players • Let different players provide different components of the network but everyone needs to agree on a new framework and related standards • Compare this to what happened with the PC industry Open Management Needed • 1960’s – 1980’s – Main Frame or Minicomputer – Dominated by IBM and DEC • 1978 – Altair the first micro-processor • Bill Gates and Paul Allen wrote Basic compiler • 1982 – The IBM PC released and that changed the world Why did the IBM PC changed the world • It allowed third parties to get involved and therefore allowing a mature industry to develop with many niche/specialist players – Visicalc, Eudora, etc • Because of DOS – A broken but open operating system • But it was the standard – Allowed new people to write applications – You didn’t have to be IBM or DEC – Also made PC affordable • The same thing has to happen in the Mobile Industry Three recent developments • Open Handset Alliance (OHA) – Founded by Google with 34 founding members • Google contributing Android – An operating system based on Linux • First GPhone about to be released • Verizon – a large Telco – Allow third party devices onto their network • FCC – Moving towards a device-agnostic spectrum policy – So third party devices would become the norm The Core Framework SERVICE PLATFORM LAYER NETWORK QOS LAYER NETWORK TRANSPORT SYSTEM NETWORK MANAGEMENT LAYER (RE)CONFIGURATION LAYER NETWORK ABSTRACTION LAYER HARDWARE PLATFORM LAYER Hardware Platform Layer Represented as Vertical Components – separate base stations 3G WLAN 802.11 WiMax 802.16 UltraWideBand Cognitive Radio will change this as it will all be done in the same box SPECTRUM MANAGEMENT 3G WLAN WiMax UltrawideBand INTELLIGENT SIGNAL PROCESSING SOFTWARE DEFINED RADIO RFEye -> unified base-station WIDE SPECTRUM REECIVER Network Abstraction Layer • Again similar to Peripheral Network – Abstraction that abstracts a number of different wireless technologies – Also includes base-station controller functions • Extension of 802.21 – Exportable interface so that the base-station can be remotely controlled – Monitoring and reporting functions (Re)configurable Layer • Controls core infrastructure including routers and switches – Programmable hardware • Routelets and Switchlets • Already used internally in network equipment but not exported to external systems especially enddevices • The concept of the programmable network hardware began with XBind – From the Comet Group led by Aurel Lazar (Columbia University, New York) Xbind • So the big idea of Xbind is that we could use it as a kernel and virtualize network infrastructure through the broadband Kernel • Layers of XBind – – – – – Applications (WWW Server) Services (e.g. Multimedia services – video conf) Broadband Kernel – Management Plane Binding Interface – Abstraction of real Hardware Real Hardware XBind – The Layers APPLICATIONS Multimedia Web Services MULTIMEDIA SERVICES Video Conf Manager BROADBAND KERNEL (High Level Abstraction and Service) Device Management, Connection Manager, Router Binding Interface Base (BIB) Virtual Switch, Virtual Link, Camera device driver, Display device driver Hardware (Real Devices and Real Network) Camera, Computers, Links, Adapters, Displays Extension of Key X-Bind Ideas • Since we can control the hardware virtually using software, the hardware and the software need not be in the same box – Make the hardware box only understand the interface – Talk to the box over a serial link using a computer – Control software runs on the computer X-BIND: The extensions MANAGEMENT CONTROL OF CONNECTIONS SERIAL LINE RAW ATM SWITCH VCI OPERATION OpenArch and OpenSig • You need a management protocol to manage the switch • You also need a signalling protocol – You need to agree on the format of the commands that go across your serial line • Two forums were established to do this – OpenArch – management plane – OpenSig – for signalling Why do we need it now? • We have never had open interfaces for mobile systems – Base-stations, BSC, MSC, etc • Because we need resources to do vertical handover, especially for client-based handover • We have to get those resources from the network – Channels on base-stations, QoS, etc Vertical Handover GPS Location, Speed, direction Connections (QoS) TBVH New QoS New IP Polling CORE NETWORK Done POLICY MANAGEMENT LAYER DECISION HANDOVER (BASE-STATION, 3G, QOS, TBVH) NETWORK MANAGEMENT LAYER Send to Mobile TOPOLOGY, RESOURCES, QoS DO IT VERTICAL HANDOVER LAYER RECONFIGURABLE LAYER ACQUIRE CHANNEL ACQUIRE RESOURCES (3G, BASE-STATION, QOS) ( 3GCHAN, BASE-STATION, QOS) DO IT NETWORK ABSTRACTION LAYER NETWORK ABSTRACTION LAYER BASE-STATION CHANNEL ACQUIRED DATA CHANNNEL = 3G 3G=ACTIVE WLAN=PASSIVE WiMAX= PASSIVE L2 events Media Info 3G WLAN WiMax 3G WLAN WiMax Handover is complicated HANDOVER ALTERNATIVE IMPERATIVE NETPREF REACTIVE UNANTICIPATED PROACTIVE ANTICIPATED KNOWLEDGE-BASED MODEL-BASED SERVICES USERPREF CONTEXT Need an Ontology for Vertical Handover • Helps us to structure the information so that the system could reason and take decisions – ICMC, USP – strong in this area – Edson Moreira, Renata Vanni and others – Reason for my recent visit to Brazil in summer 2008 The Network Management Layer • Defines and controls several networks • Each network is controlled by a network operator • Support for network virtualization and partitioning – Several networks managed by different network operators but on the same extended hardware platform • Will facilitate regional or city-wide operators Network Management What we want • Networks to be managed in a flexible way • An interface that defines and manages an entire network in terms of programmable components, including switchlets, routelets, etc. – i.e. network virtualization • using software abstraction to control the network • Create new networks (spawning) • Merge and partition networks NETWORK MANAGEMENT Network Topologies Network Resources HIGH-LEVEL FUNCTIONS CREATE MODIFY MERGE JOIN NETWORK 1 Network Components NETWORK 2 NETWORK 3 NETWORK 4 (RE)CONFIGURATION LAYER Core Transport System • Concerned about moving data between points in the core network • TCP/IP is the Transport and Network protocols for the Internet • Migration of IPv4 to IPv6 – Important for the new framework – Need enhancements • Easier mechanisms to support security – VPNs, Tunnelling, etc Core Transport in Y-Comm PERIPHERAL WIRELESS NETWORK CORE NETWORK QoS, Secure Connection PERIPHERAL WIRELESS NETWORK Core Endpoints In Access Network Core Transport: Making Connections between Core Endpoints Make connection Between Wireless Networks CORE TRANSPORT LAYER ENDP1, ENDP2, QoS Routing, Security NETWORK MANAGEMENT LAYER Network QoS Layer • Most of the QoS issues are now in the Peripheral Network • Current End-to End QoS models – IntServ • Largely abandoned – DiffServ • Slow deployment • Need to explore network QoS models – Negotiation structure between Core Network and Peripheral Networks Enhance QoS Functionality Negotiating with Peripheral Networks CORE NETWORK QOS ENDPT1 ENDPT2 ENDPT3 PER FLOW (IntServ), PER CLASS (Diffserv) Service Platform • Services developed by third parties • Should be able to configure services on several networks at the same time • Support for installing services for specific types of networks – London travel service available to networks around London SERVICE PLATFORM LAYER • Installation – Install over many networks simultaneously – Specifying QoS (minimum SLA) • Server Advertisement and Subscription • Session management – Interaction between server and application running on the mobile node • Supporting Mobility – How is QoS maintained even though the mobile is moving • Server replication, proxy server support Service Platform and Core Network Server Advertisement Subscription Applications SERVICE PLATFORM LAYER Negotiating with Peripheral Networks SLA1 SLA2 ENDPT1 CORE NETWORK QOS ENDPT2 SLA3 ENDPT3 SLA 4 ……. PER FLOW (IntServ), PER CLASS (Diffserv) Need to Address Security • Cannot be a separate Layer in the architecture as there are different kinds of security issues • Y-Comm defines a 4-layer security architecture • Comprehensive Design – Security system is integrated into the structure of Y-Comm Security in Y-Comm • Network Architecture Security (NAS) • Security dealing with the deployment and management of different wireless technology • Managed from the Policy and Management layers • Network Transport Security (NTS) – Security dealing with end-to-end transport through Y-Comm • Done at Layer 5, NAT, IPSec, etc • QoS Based Security (QBS) – Look at QoS Issues • Looks at SLAs, prevents overloading • Looks at Denial of Service Attacks • Service and Application Security (SAS) – Security dealing with running applications and deploying services • AAAC, ACLs, User-based security The Y-Comm Framework showing its Security Levels- New Security Level CORE NETWORK PERIPHERAL NETWORK APPLICATION ENVIRONMENTS QOS LAYER END SYSTEM TRANSPORT POLICY MANAGEMENT SAS QBS NTS NAS SERVICE PLATFORM NETWORK QOS LAYER CORE TRANSPORT NETWORK MANAGEMENT VERTICAL HANDOVER (RE)CONFIGURATION LAYER NETWORK ABSTRACTION (MOBILE NODE) NETWORK ABSTRACTION (BASE STATION) HARDWARE PLATFORM (MOBILE NODE) HARDWARE PLATFORM (BASE STATION) Research Collaboration • Y-Comm is really too big to be done by one person or one group • Building a global research network to study Y-Comm • Not trying to implement everything – Using the effort and experience of others – A number of IEEE Working Groups • 802.21, 802.22 Group so far.. • University of Cambridge • Proactive knowledge- based policy mechanisms for handover (David Cottingham) • Network issues around changing IP (Jon Crowcroft) • QoS-aware middleware services (Aisha El-safty) • Middlesex University • Mathematical modelling of vertical handover (TBVH) and the Stream Bundle Layer for Downward QoS (Fatema Shaikh) • Transport protocol and network architecture issues in Peripheral networks (Glenford Mapp) Group so far • University of Sao Paulo (ICMC San Carlos) • Ontological services for vertical handover • SoHand Middleware (Edson Moreira and Renata Vanni) • University of Trinidad and Tobago (UTT) • Service platform for Y-Comm (Wayne Butcher) • Loughborough University • Security Framework in Y-Comm (Raphael Phan) • Dartmouth College (USA) • Intelligent Physical Spaces(Andrew Campbell) • St Andrews University? Lots of Interaction • Y-Comm Forum Day – 2nd one was held on 2nd July at Cambridge • Building a global research network is new – Visit to Brazil:- key to establishing global collaboration • Journal Paper on Y-Comm • Submitted to IEEE/ACM TON – URL for Y-Comm White Papers • http://www.cl.cam.ac.uk/research/dtg/?userid=gem11 New Plans at Middlesex • Develop a small Y-Comm testbed at Middlesex • Go further than the Cambridge Testbed • Include Industrial Partners • Vodafone, CRFS Limited, Univirtua • Involve the MUBS • Look for a new business model for Y-Comm • Host the Y-Comm Research Web Page – http://www.mdx.ac.uk/eis/research/groups/YComm.asp Any Questions?