Seamless integration of heterogeneous wireless network technologies -?/! Jochen Schiller Computer Systems & Telematics Freie Universität Berlin Germany schiller@computer.org Prof. Dr.-Ing. Jochen Schiller, http://www.jochenschiller.de/ ASWN 2003 1
Mobile and wireless services Always Best Connected AN, WLAN 80 kbit/s GSM 53 kbit/s Bluetooth 500 kbit/s UMTS, GSM 115 kbit/s LAN 100 Mbit/s, WLAN 54 Mbit/s UMTS, DECT 2 Mbit/s GSM/EDGE 384 kbit/s, WLAN 780 kbit/s GSM 115 kbit/s, WLAN 11 Mbit/s UMTS, GSM 384 kbit/s Prof. Dr.-Ing. Jochen Schiller, http://www.jochenschiller.de/ ASWN 2003 2
Wireless systems: overview of the development 1981: NMT 450 1986: NMT 900 cellular phones 1992: GSM 1994: DCS 1800 1991: CDMA 1983: AMPS 1991: D-AMPS 1993: PDC 1982: Inmarsat-A 1988: Inmarsat-C satellites 1992: Inmarsat-B Inmarsat-M 1998: Iridium cordless phones 1980: CT0 1984: CT1 1987: CT1+ 1989: CT 2 wireless LAN 1991: DECT 199x: proprietary 1997: IEEE 802.11 1999: 802.11b, Bluetooth analogue digital 2000: GPRS 4G fourth generation: when and how? 2001: IMT-2000 200?: Fourth Generation (Internet based) 2000: IEEE 802.11a Prof. Dr.-Ing. Jochen Schiller, http://www.jochenschiller.de/ ASWN 2003 3
Overlay Networks - the global goal (since many years) integration of heterogeneous fixed and mobile networks with varying transmission characteristics regional vertical handover metropolitan area campus-based horizontal handover in-car, in-house, personal area Prof. Dr.-Ing. Jochen Schiller, http://www.jochenschiller.de/ ASWN 2003 4
Wireless access technologies DAB relative speed [km/h] 250 100 50 5 0 GSM, TETRA EDGE FDD UMTS DECT TDD Bluetooth 802.11b physical/ economic border HiperLAN2, 802.11a/.11g Point-to-multipoint distribution systems 10 kbit/s 2 Mbit/s 20 Mbit/s bandwidth 150 Mbit/s Prof. Dr.-Ing. Jochen Schiller, http://www.jochenschiller.de/ ASWN 2003 5
Example IP-based 4G/Next G/ network PSTN, CS core SS7 signalling server farm, gateways, proxies broadcast gateways MSC GSM BSC SGSN IP-based core router firewall, GGSN, gateway Internet RNC access points private WPAN private WLAN UMTS public WLAN Prof. Dr.-Ing. Jochen Schiller, http://www.jochenschiller.de/ ASWN 2003 6
What helps us to provide seamless services? Improved radio technology and antennas smart antennas, beam forming, multiple-input multiple-output (MIMO) space division multiplex to increase capacity, benefit from multipath software defined radios (SDR) use of different air interfaces, download new modulation/coding/... requires a lot of processing power (UMTS RF 10 TIPS = 10000000 MIPS) dynamic spectrum allocation spectrum on demand results in higher overall capacity Core network convergence IP-based, quality of service, mobile IP Simple and open service platform intelligence at the edge, not in the network (as with IN) more service providers, not network operators only Ad-hoc technologies spontaneous communication, power saving, redundancy Prof. Dr.-Ing. Jochen Schiller, http://www.jochenschiller.de/ ASWN 2003 7
Practical scenarios for mobile ad-hoc networks 1 Only a very few scenarios! For real, i.e., multi-hop ad-hoc networks (besides military apps.) Typically in the area of environmental monitoring, disaster protection and recovery EWS Bluetooth EWS EWS EWS WLAN www.scatterweb.net Prof. Dr.-Ing. Jochen Schiller, http://www.jochenschiller.de/ ASWN 2003 8
Practical scenarios for mobile ad-hoc networks 2 any scenarios! For ad-hoc connections to infrastructures, ad-hoc service usage, ad-hoc peer-to-peer networking (gaming!) RF RF sensors VPN VPN VPN Bluetooth Bluetooth VPN www.discourse.de RF actuato RF e prepared for ad-hoc situations Do not rely on infrastructures Support ad-hoc usage of services & ad-hoc changes of connectivity Prof. Dr.-Ing. Jochen Schiller, http://www.jochenschiller.de/ ASWN 2003 9
Potential problems Quality of service Today s Internet is best-effort Integrated services did not work out Differentiated services have to prove scalability and manageability What about the simplicity of the Internet? DoS attacks on QoS? Internet protocols are well known also to attackers, hackers, intruders security by obscurity does not really work, however, closed systems provide some protection Reliability, maintenance Open question if Internet technology is really cheaper as soon as high reliability (99.9999%) is required plus all features are integrated Missing charging models Charging by technical parameters (volume, time) is not reasonable Pay-per-application may make much more sense Killer application? There is no single killer application! Choice of services and seamless access to networks determine the success Prof. Dr.-Ing. Jochen Schiller, http://www.jochenschiller.de/ ASWN 2003 10
Services & apps. in future cellular/wireless networks Voice, voice, voice, Still is and will be for a long time the predominating service Internet access Very convenient for email, search, messaging, Combinations Use the mobile device as RFID reader, as navigation tool, (swiss knife) but don t try to do everything with it (toolbox) Gaming, Entertainment Do something while waiting Prof. Dr.-Ing. Jochen Schiller, http://www.jochenschiller.de/ ASWN 2003 11
What about security across different systems? Needed? Absolutely, but Seamlessness ~ Security³ Achievable? It is not a question of technology! Do the operators want it? Yes to protect their own systems, not always if it comes to customers Do users want to pay for it? No, only after something happened Do operators want to cooperate? Not always see GSM black lists Prof. Dr.-Ing. Jochen Schiller, http://www.jochenschiller.de/ ASWN 2003 12
Seamless integration of wireless networks & services Will it ever happen? Yes, from a technical point of view No, from a marketing point of view Should it happen? Yes, from a user s perspective Smother ride on the wireless Internet No, from a user s perspective If this ties me to a certain operator, compromises privacy, hides pricing, Almost seamless is fine for most applications! Think of transport systems (Trains, cars, airplanes, ) Fine if the connection works + handover time is short Protects users and systems Try to call your sysadmin with an IP-phone to tell him that the network is down Prof. Dr.-Ing. Jochen Schiller, http://www.jochenschiller.de/ ASWN 2003 13