Presentation on theme: "Copyright, 1995-2004 1 Issues from Internet Technologies 1 – Internet Connected Devices Roger Clarke, Xamax Consultancy, Canberra Visiting Prof/Fellow,"— Presentation transcript:
Copyright, 1995-2004 1 Issues from Internet Technologies 1 – Internet Connected Devices Roger Clarke, Xamax Consultancy, Canberra Visiting Prof/Fellow, Unis of N.S.W., Hong Kong, A.N.U. http://www.anu.edu.au/people/Roger.Clarke/........II/CCCS-1-ICD.ppt UofQ CCCS, 6 December 2004
Copyright, 1995-2004 2 Internet Connected Devices Agenda Stationary Devices and Cable-Based Comms Wireless Comms Mobile / Portable / Handheld Devices Appliances / White Goods Smartcards / RFID Chips / Smart Dust Issues in Mobile
Copyright, 1995-2004 3 Stationary Devices / Cable-Based Comms Public Access Points Workstations in the workplace Work, Study and Play'-stations in the home (PCs, perhaps TV sets, perhaps games- stations) Public Kiosks, e.g. tourism/Datatrax Private Kiosks e.g. ATMs PCs in libraries, communities, schools PCs in 'Internet Cafes', airport lounges, clubs Playstations in games-arcades
Copyright, 1995-2004 4 The Internet moves into the Mobile Era
Copyright, 1995-2004 5 Mobile / Portable / Handheld Devices Public Access Points Faxes (for printouts) and Phones (e.g. for spoken email) Private mini-workstations (e.g. in Boeing 777s) Portables, at docking stations Handhelds / PDAs Mobile Phones Music Playstations – Walkman,..., iPod,... Games Playstations in the hand Digital cameras, still and video
Copyright, 1995-2004 6 End-Point Device Capabilities Radio Studios TV Studios Fixed Telephones Fax-Machines PCs Mobile Telephones PDAs Digital Cameras Games Consoles? Music Mixers? Radios TV sets Fixed Telephones Fax-Machines PCs Mobile Telephones PDAs Digital Cameras Games Consoles? Music Players?
Copyright, 1995-2004 7 Mobile Technologies and Protocols Characteristics At least some of the devices in the network have at least some of the following characteristics: are in different locations at different times might be anywhere (pervasive, ubiquitous) are moving relative to the earths surface cannot sustain cable-based connections have limited capacity, incl.: processing, storage display, input power-source
Copyright, 1995-2004 8 Wireless Comms Using Electromagnetic Radiation Wide Area Networks – Satellite (Geosynch, Low) GS is Large footprint, very high latency (c. 2 secs) Wide Area Networks – Cellular (to 20km per cell) 1 – Analogue Cellular, e.g. AMPS, TACS 2 – Digital Cellular, e.g. GSM, CDMA 3 – 3G, e.g. GSM/GPRS and W-CDMA Wide Area Networks – WiMax, IEEE 802.16 Local Area Networks – WiFi (10-100 m radius) e.g. IEEE 802.11x esp. 11b,g / Apple Airport Personal Area Networks (1-10 metres) e.g. Bluetooth (or beamed infra-red)
Copyright, 1995-2004 9 Mobiles vs. Fixed IP Addresses The Problem Each Internet-connected device must use an IP-Address from within the range of values assigned to the sub-net that its connected to A sub-net is generally defined to be a LAN, a cell, a Wifi hotspot or a satellite footprint If a device moves from one sub-net to another, it will no longer be reachable at the old IP-Address So when a device moves to a new sub-net, it has to abandon its old IP-Address and get a new one That interrupts TCP sessions; perhaps frequently
Copyright, 1995-2004 10 Mobiles vs. Fixed IP Addresses The Solution Under IPv4, all possible solutions are clumsy The next version of IP, IPv6, supports Mobile IP Mobile IP allows a device to maintain the same IP-Address wherever it attaches to the network Mobile IP uses the concept of a care-of address This is managed by a home agent on the home subnet of the mobile device, which performs re-direction of the traffic (hopefully, fast enough)
Copyright, 1995-2004 11 W3Cs Device-Independence Strategy Access is needed from many device-types, e.g.: cellular phones TV digital cameras in-car computers There is a risk that many device-types may only be able to access parts of the Web W3C is dedicated to ensuring that the Web universe is not fragmented. Interoperable languages and protocols, and single-authored content should prevail
Copyright, 1995-2004 12 Appliances / White Goods Your fridge, air-conditioner and door-locks: are becoming intelligent can do things need information in order to do it know a lot about you Your car can talk with them So can your mobile devices And theyre liable to be promiscuous
Copyright, 1995-2004 13 Smartcards / RFID Chips / Smart Dust (Would you like chips with that?) In principle, any carrier will do Insecure and Promiscuous, unless: sufficient processor / memory capacity sufficient power when its needed consumer requirements defined consumer requirements implemented two-way device authentication
Copyright, 1995-2004 14 Are Mobile Devices Locator Mechanisms? Is there a back-channel from the mobile party? cf. a simple GPS handset How big is the area or cell? If the network knows: do other parties to communications? do third parties? Can the mobile party use a proxy-server to deny, obscure or falsify location information?
Copyright, 1995-2004 15 Some Issues in Mobile Massive investments Clash between multimedia demands and channel bandwidth capacity – fixed, wireless Low security Insufficiently rich set of payment mechanisms Considerable infrastructural variations Enormous cultural variations Highly varied outcomes