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Exploring a Framework for Developing the Future Internet: Lessons from the Y-Comm Architecture Glenford Mapp Principal Lecturer, Middlesex University PURSUIT 2011 Computer Lab Outline of the Talk • • • • • • Motivation for the work Our approach Introduction to Y-Comm Peripheral Framework Areas of Work Conclusions PURSUIT 2011 Computer Lab Motivation (looking backward) • Originally we started with ubiquitous handover. – Fore-runner was work on the Cambridge Wireless network which looked how you do handover between different wireless systems • James Scott, Leo Patanapongpibul, Pablo Vidales – YComm ended up looking at ubiquitous handover, Quality-of-Service, Security and Application environments/Service Platforms PURSUIT 2011 Computer Lab Lesson -1.0 • Each of these are big areas in themselves – Can study each area on its own and that is what a lot of people are doing. • End up with good papers but not something that you could take and build a real system • We took the opposite viewpoint. – Try to describe the big picture first • Develop the mechanisms but keep always keep the big picture in view PURSUIT 2011 Computer Lab Lesson -0.5 • Don’t be foolish – Invent things only when you need to • Y-Comm is not trying to invent new technologies for the sake of it – Use standards or new technologies • Be futuristic – Take a guess but realize you could be wrong – Allow evolution – Be conservative PURSUIT 2011 Computer Lab Futuristic Assumption 1: Network Evolution • The Internet will evolve in a physical sense • 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 • Consequences • Degradation of end-to-end arguments PURSUIT 2011 Computer Lab Internet Evolution BACKBONE ACCESS NETWORKS WIRELESS NETWORKS PURSUIT 2011 Computer Lab Futuristic Assumption 2: Heterogeneous Devices • Devices will have more than one wireless interface. • Vertical handover – switching between different network interfaces to provide seamless connectivity • Vertical handover is good but it introduces a lot of QoS issues because the different wireless networks have different qualities of service PURSUIT 2011 Computer Lab Vertical Handover (Sideffects) • Affects your connections – Some protocols react badly with respect to handover. • Affects your applications – Need to think through how Quality-of-Service affects applications • Encapsulate these ideas in a Framework PURSUIT 2011 Computer Lab Layer 5: Slow Adaptation of TCP After LAN->GPRS Handover PURSUIT 2011 Computer Lab Lesson 0.0 • New framework – We need to control network interfaces generically – Make mobility support explicit • Vertical handover can have tsunami effects – Merge network and transport services – Make QoS support explicit • Provide a way for applications to negotiate with the network PURSUIT 2011 Computer Lab The Complete Y-Comm Framework CORE NETWORK PERIPHERAL NETWORK APPLICATION ENVIRONMENTS SAS SERVICE PLATFORM QBS QOS LAYER END SYSTEM TRANSPORT POLICY MANAGEMENT NETWORK QOS LAYER CORE TRANSPORT NTS NAS NETWORK MANAGEMENT VERTICAL HANDOVER (RE)CONFIGURATION LAYER NETWORK ABSTRACTION (MOBILE NODE) NETWORK ABSTRACTION (BASE STATION) HARDWARE PLATFORM (MOBILE NODE) HARDWARE PLATFORM (BASE STATION) PURSUIT 2011 Computer Lab Y-Comm Group • 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) • Security (Mahdi Aiash) • Mobile Services (Fragkiskos Sardis) • University of Cambridge • Proactive knowledge- based policy mechanisms for handover (David Cottingham) • Networking issues (Jon Crowcroft) PURSUIT 2011 Computer Lab Y-Comm Group • University of Sao Paulo (ICMC San Carlos) • Ontological services for vertical handover • SoHand Middleware (Edson Moreira and Renata Vanni) • Core Network Management (Mario Augusto) • Federal University of San Carlos • Testbed based on IEEE 802.21 • Loughborough University • Security Framework in Y-Comm (Raphael Phan) PURSUIT 2011 Computer Lab This talk • Can’t explain everything about Y-Comm • It’s too big • Concentrate on the Peripheral Network • See Y-Comm Research Webpage: • http://www.mdx.ac.uk/research/areas/soft ware/ycomm_research.aspx PURSUIT 2011 Computer Lab The Peripheral Framework APPLICATION ENVIRONMENTS LAYER QOS LAYER END TRANSPORT SYSTEM POLICY MANAGEMENT LAYER VERTICAL HANDOVER LAYER NETWORK ABSTRACTION LAYER HARDWARE PLATFORM LAYER PURSUIT 2011 Computer Lab 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 PURSUIT 2011 Computer Lab Hardware Platform Layer Represented as Vertical Components 3G WLAN 802.11 PURSUIT 2011 WiMax 802.16 UltraWideBand Computer Lab 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 PURSUIT 2011 Computer Lab 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 PURSUIT 2011 Computer Lab Cognitive Radio SPECTRUM MANAGEMENT 3G WLAN WiMax UltrawideBand INTELLIGENT SIGNAL PROCESSING SOFTWARE DEFINED RADIO WIDE SPECTRUM REECIVER PURSUIT 2011 Computer Lab 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 PURSUIT 2011 Computer Lab 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 PURSUIT 2011Handovers Computer Lab Layer 3: Vertical Handover Layer • Layers that define the mechanism for vertical handover. • Support for different types – Network-based – Client-based PURSUIT 2011 Computer Lab 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 PURSUIT 2011 Computer Lab Lesson 1.0 handover is complicated HANDOVER ALTERNATIVE IMPERATIVE NETPREF REACTIVE UNANTICIPATED PROACTIVE SERVICES USERPREF CONTEXT ANTICIPATED KNOWLEDGE-BASED MODEL-BASED PURSUIT 2011 Computer Lab Layer 4: Policy Management layer • Decides if, when and where vertical handover should occur. • Must be able to deal with all cases of handover – Reactive done – Proactive – most favourable but hard PURSUIT 2011 Computer Lab Reactive Policy: PROTON HIGHER LAYERS Interface Information L2 Triggers INPUT/OUTPUT LAYER POLICY LAYER (PONDER) HANDOVER EXECUTION LAYER WLAN GPRS PURSUIT 2011 LAN Computer Lab 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 PURSUIT 2011 Computer Lab 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 PURSUIT 2011 Computer Lab 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 PURSUIT 2011 Computer Lab Knowledge-Based Policy Management (Cambridge) PURSUIT 2011 Computer Lab 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 PURSUIT 2011 Computer Lab The Model-Based Handover Handover threshold circle Exit threshold circle Threshold Circle coverage Real coverage Exit coverage PURSUIT 2011 Computer Lab 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 ) • BBS r d x z MS Estimated TBVH r 2 d 2 sin 2 x d cos x TBVH v PURSUIT 2011 Computer Lab Simulation and Results TBVH simulation in OPNET Modeler: PURSUIT 2011 Computer Lab Combining Transport and Communications to determine the optimum handover NET A A NET B S B NET C C T PURSUIT 2011 Computer Lab Analysis shows that it is possible to calculate these key points with some degree of accuracy C1 E1 Y2 Z1 A S Y1 H1 Y3 C2 B E2 C E3 H3 H2 T PURSUIT 2011 Z2 Z3 Computer Lab This is getting interesting • Because we can not only work out TBVH • You can also calculate the amount of time a mobile node will be in a given network • Try to optimize handovers when networks overlap – Depends on the velocity (affects the exit radius) and adaptation time PURSUIT 2011 Computer Lab 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 PURSUIT 2011 3G WLAN WiMax Computer Lab Lessons 2.0: We need to move to Locationbased Information infrastructure • Leads to better handover – Leads to a much better use of network infrastructure – It needs to tell the mobile node about individual networks • Power of the transmitter, where the access points are located. – It also needs to know about the relationships between the individual networks. PURSUIT 2011 Computer Lab 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 PURSUIT 2011 Computer Lab 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 PURSUIT 2011 Computer Lab 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 PURSUIT 2011 Computer Lab Y-Comm’s view of the Future PERIPHERAL WIRELESS NETWORK CORE NETWORK QoS, Secure Connection PERIPHERAL WIRELESS NETWORK PURSUIT 2011 Core Endpoints In Access Network Computer Lab View corresponds with other ideas • Faster LAN systems – Optimize DNS, streaming video from local caches • Integrate protocol with applications – Tuneable transport – Remove the user/kernel limitations • Use as a local signalling protocol – Encapsulates TCP packets PURSUIT 2011 Computer Lab Simple Protocol DEST_ID SRC_ID CHKSUM PK_TYPE PRI CB Flags TOTAL_LEN PBLOCK MESS_ACK_NO MESS_SEQ_NO SYNC_NO TBLOCK WINDOW_SIZE PURSUIT 2011 Computer Lab The Simple Protocol • • • • • • • • • • • • • DEST_ID (16) – identifying remote end SRC_ID (16) – from source end PK_TYPE (4) - packet type PRI (2) - supports 4 priority levels CB (2) – supports ECN CHKSUM (16) – sixteen bit checksum TOTAL_LEN (16) – total packet length PBLOCK (8) – the present block TBLOCK (8) – the total number of blocks MESS_SEQ_NO (16) – last message sent MESS_ACK_NO (16) – last message received SYNC_NO (8) – the last ACK received WINDOW_SIZE (24) – the window size PURSUIT 2011 Computer Lab Lesson 3.0: Local support is now essential to the Future Internet • • • • Presence of heterogeneous networks Support for mobility Need for local signalling Need for local transports – Don’t need to change TCP • Need for local knowledge • Can’t ignore that any more PURSUIT 2011 Computer Lab Heterogeneous Networking and Multi-homing • Because devices will have several interfaces, there will be multi-homing issues • Solutions such as Mobile IP which depend on Home and Care-of-Addresses are not scalable • SCTP helps but works on the transport level only • Need to look at the network addressing scheme PURSUIT 2011 Computer Lab Does IPv6 help? Look at the IPv6 Address Format PURSUIT 2011 Computer Lab Advantages of IPv6 • Uses a global Interface_ID so it is very easy to construct a new address using auto-configuration – So I don’t need a foreign agent – Since the Interface_ID does not change if I do a horizontal handover, it is easier for the network infrastructure to work out what is going on • Does not help with vertical handover PURSUIT 2011 Computer Lab Pressure for Change • Mobile Systems – Efficient Vertical Handover (Y-Comm) • Multi-path TCP – Allowing TCP to use all the device interfaces to transfer data • IETF, Jon Crowcroft, Cambridge • Pressure to optimize network resources – Switches and routers have limited memory, etc. • Internet of Things – Networking should be based around devices themselves not the interfaces they use PURSUIT 2011 Computer Lab Different Approach • Split the IP address into 2 distinct parts – Node_ID : identifies the device • Independent of the number of Interfaces the device has • Given when the device was created; burnt into device; • Recycled when the device is no longer used – Location_ID: identifies which network the device is using. A multi-homed device will have several Location_IDs PURSUIT 2011 Computer Lab Proposed IP Address Format 0 63 127 LOCATION_ID PURSUIT 2011 NODE_ID Computer Lab History behind this • First proposed by LIN Group in Japan (20002001) • Some work done at AT&T Labs on supporting this paradigm – Mapp and Fraser (2001) • Led to the development of EUI-64 – Evolve the Ethernet Mac Address into a Node_ID • Current work on ILNP lead by Saleem Bhatti from St Andrews PURSUIT 2011 Computer Lab Why is this good? • Node_ID allows the networking infrastructure to know that network interfaces are co-located • Optimize network resources – In the core network we could use the Node_ID as a general guide to where the device is located. Use the Location_ID to choose which particular local network to use to forward the packet to that device – Refinement of HMIPv6 PURSUIT 2011 Computer Lab Additional Help is needed • Some observations – It would be good to know that the device is stationary in a given network • Cache the Location_ID directly in the routing table – Good for servers as they are stationary – Reduce the visibility of servers • Need to reduce DDoS attacks – Support of using different interfaces • Multicast, broadcast, local any-cast, etc. PURSUIT 2011 Computer Lab So we are proposing to modify to address format 63 0 LOCATION_ID 0 55 LOCATION_ID 127 NODE_ID 63 NET ADMIN PURSUIT 2011 127 NODE_ID Computer Lab NEW STRUCTURES 0 39 GLOBAL ROUTING PREFIX LOCATION_ID = 0 NETADMIN SUBNET 8 SF S = 55 M INF 0 NODE_ID = 63 Global Node Identifier (EUI-64) PURSUIT 2011 Computer Lab SF- Scope Field • Introduced by the Y-Comm Group – Ring-based Security model • Aimed at protecting servers by reducing access to them • Servers act within a defined network scope – Only entities within that scope can access the server – If you are outside the scope, your packet is blocked by the network infrastructure PURSUIT 2011 Computer Lab Scope Field – 2 bits • 00 - Only processes on the same machine can use this server • Location_ID must be the loop-back address • 01 - Only processes on the same LAN can access the server • Location_ID must be the same LAN as server • 10 – Only processes on the same Admin Domain can access the server • Location_ID must be site-address • 11 – Server is globally accessible PURSUIT 2011 Computer Lab Other bits in the NetAdmin Field • S – indicates that the device is stationary with regard to a given network – Physically stationary – Servers – Relatively stationary as determined by a location system • M – indicates that Node_ID is being used as a multicast address, this allows multicast packets to be sent on network PURSUIT 2011 Computer Lab Interface_IDs can make a comeback • Interface_IDs banished from the New address format – Means we will have to map the Location_ID to the Interface_ID before we could send a packet on a given network. Slow performance • Other observation – Bluetooth and other short range systems do not need a Location_ID (network) and Interface_ID might be better PURSUIT 2011 Computer Lab Re-Introduce it by indirectly INF field (4 bits) • An interface can be uniquely represented within the address format by using an interface number – Controlled by the device. • Map interface # to MAC address • Give special meaning to certain values – 0 – any-cast – packet is sent on any available network interface of the mobile device – 0xF – broadcast packet is sent on all available network interfaces of the mobile device – 0x1 – called the primary interface PURSUIT 2011 Computer Lab INF • Support for pseudo/virtual interfaces – Add features such as security • OpenSSL, FreeSwan, provides IPSec services • Applications can query interfaces on a device – Master locator – Map interfaces #s to Quality-of-Service (QoS) parameters • Bluetooth and other point-to-point system could use the INF only and not bother with the Location_ID PURSUIT 2011 Computer Lab Lesson 4.0: Can’t ignore multihoming any longer • Crucial for heterogeneous networking • Need to concentrate on devices and not their interfaces • Need to think about keeping it flexible and efficient • Urgent PURSUIT 2011 Computer Lab 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 PURSUIT 2011 Computer Lab 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 PURSUIT 2011 Computer Lab 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 PURSUIT 2011 Computer Lab QoS Layer DOWNWARD QOS UPWARD QOS APPLICATION LAYER APPLICATION LAYER QOS LAYER QOS LAYER END TRANSPORT LAYER END TRANSPORT LAYER POLICY MANAGEMENT LAYER PURSUIT 2011 POLICY MANAGEMENT LAYER Computer Lab Lesson 5.0 Make QoS the real interface to the network • Applications should not really have to know about TCP or any other protocol • Replace transport protocols on the fly • Allow applications to adapt if they can PURSUIT 2011 Computer Lab Last area: Security • Security is part of Quality-of-Service • QoSS – specify security as part of QoS – Changes in security are regarded as changes in the QoS • Security needs to be on different levels and involves both Core and Peripheral Frameworks • Allow several layers PURSUIT 2011 Computer Lab The Y-Comm Framework showing its Security Levels- New Security Level CORE NETWORK PERIPHERAL NETWORK APPLICATION ENVIRONMENTS SAS SERVICE PLATFORM QBS QOS LAYER END SYSTEM TRANSPORT POLICY MANAGEMENT NETWORK QOS LAYER CORE TRANSPORT NTS NAS NETWORK MANAGEMENT VERTICAL HANDOVER (RE)CONFIGURATION LAYER NETWORK ABSTRACTION (MOBILE NODE) NETWORK ABSTRACTION (BASE STATION) HARDWARE PLATFORM (MOBILE NODE) HARDWARE PLATFORM (BASE STATION) PURSUIT 2011 Computer Lab 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 PURSUIT 2011 Computer Lab Lesson 6: Security needs to consider the effect of an open Architecture • Security needs to be part of the communications system • Also needs to be part of QoS • Security is about protecting entities and not just data – Concept of Security models • Connection • Ring-based • Vertical Handover PURSUIT 2011 Computer Lab Lesson 7: New business models • Y-Comm is doomed to failure • No academic funding – Not about TCP/IP – Not interested in tinkering around the edges • No industry funding – Y-Comm will destroy the revenue streams of current mobile providers – They will not put money in unless we show them how they are going to make money PURSUIT 2011 Computer Lab Any Questions? PURSUIT 2011 Computer Lab