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, 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. UofQ CCCS, 6 December 2004
Copyright, 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, 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, The Internet moves into the Mobile Era
Copyright, Mobile / Portable / Handheld Devices Public Access Points Faxes (for printouts) and Phones (e.g. for spoken ) 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, 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, 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, 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 Local Area Networks – WiFi ( m radius) e.g. IEEE x esp. 11b,g / Apple Airport Personal Area Networks (1-10 metres) e.g. Bluetooth (or beamed infra-red)
Copyright, 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, 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, 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, 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, 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, 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, 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