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Click to edit Master text styles,Second level,Third level,Fourth level,Fifth level,Presentation,Slide,*,Click to edit Master title style,Wireless and its Security,Jing Tan,Department of Computer Science,University of Massachusetts,Lowell,jtancs.uml.edu,Presentation,1,My message,Its(Wireless Security)not too late,but its time to start.,Presentation,2,History of Wireless,Wireless Technologies are relatively old.,The development of wireless started about a century ago,The wireless played an important role from world war II to aircraft business and NASA space exploration.,But now the wireless technology has developed into one of todays hottest topics because of its ability to bring the power of communications and the Internet into the hands of users worldwide.,Presentation,3,The Growth of WLANs,Demand for wireless access to LANs is fueled by the growth of mobile device.There will be over a billion mobile devices by 2003,and the wireless LAN market is projected to grow to over US$20 billion by 2003.,Internet,Presentation,4,The Technologies,The wireless technologies,802.11 and 802.11b,Wireless Application Protocol(WAP),Wired Equivalent Privacy(WEP),Presentation,5,Whats 802.11/802.11b?,802.11 and 802.11b standard,In 1997 IEEE published the first world-recognized standard for wireless,802.11.About two years later,the IEEE published 802.11b,also know as 802.11 High Rate,which specifies the standards for building wireless system that operate with data speeds of up to 11Mbps.,Presentation,6,Detail of 802.11/802.11b,Wireless Architecture Modes,802.11b physical layer,801.11 Media Access Control Layer(MAC),Presentation,7,Wireless Architecture Modes,Architecture Modes,Infrastructure mode(802.11),All stations in the system connect to an access point,not directly to one another.,BBS(Basic Service Set)and ESS(Extended Service Set),Ad hoc,mode(Bluetooth),The stations interconnect directly,without communicating through an access point.,Presentation,8,802.11b physical layer,802.11b physical layer,One of the most valuable additions the 802.11b standard provides is the standardization for the physical layer support of the two new speeds,5.5Mpbs and 11Mbps.,To increase the data rate in 802.11b,advanced coding techniques are described,Presentation,9,801.11 Media Access Control Layer(MAC),801.11 Media Access Control Layer(MAC),801.11 MAC is designed to support multiple users on a shared medium by having the sender detect and gather information about the medium before accessing it.,It is same as the 802.3 Ethernet wire connection.However the protocol employed CSMA/CD(carrier sense multiple access with collision detection)details collision handing and redirection.,In 801.11,collision detection is not possible because stations cannot listen and transmit at the same time;the radio transmission prevents the station from sending a collision.The protocol specified is slightly different from that in 802.3.It is termed CSMA/CA(carrier sense multiple access with collision avoidance)involves sending extra packets to confirm receipt to transmitted packets,called explicit packet acknowledgment(ACK).,Presentation,10,Wired Equivalent Privacy,Wired Equivalent Privacy(WEP),The WEP protocol algorithm is designed on five premises:,Reasonably strong.Takes a reasonably long time to break the encryption.,Self-synchronizing.,Its not too much based on battery power.,Exportable.Can be moved when necessary.,Optional.Can be turned on and off when a user needs.,Presentation,11,Bluetooth,Bluetooth,Unlink 802.11,Bluetooth,is a technology that operates in ad hoc network.,Presentation,12,Wireless Application Protocol,Wireless Application Protocol(WAP),WAP is considered by some to be the standard in wireless communications.Main members are Nokia,Ericsson,and Motorola,etc.,WAP has WTLS(Wireless Transport Layer Security)equivalent to Transport Layer Security(TLS)or Secure Socket Layer(SSL)provides authentication,privacy,and secure connections between applications.The problem with WTLS is that it does not provide end-to-end security and opens its holes.,Presentation,13,WAP Overview,The subscriber push a key on her phone that has a URL(),WAP gateway(AP).receives,WTP/WTLS package and translated into,HTTP/HTTPS to web server.,The web server passes the requested file with HTTP/SSL the returned data to the gateway.,The Gateway performs translation into WML.,The problem starts at this point.It does not provide end-to-end security and opens holes.,WTP,WTLS,WAP Gateway(AP),Internet,Web Server,HTTP/HTTPS,SSL,Presentation,14,The Languages,The wireless languages,WAP Browsers,Wireless Markup Language(WML),WMLScript,Java 2 Micro Edition(J2ME),C#,XHTML,Wireless Operating System,Presentation,15,WAP Browsers,WAP Browsers,More and more pages on the wireless web are being written in WML to avoid having to translate to or from HTML.To view a WML page,a device must have a browsers are Netscape,IE and Openwave Mobile Browser.,Presentation,16,Wireless Markup Language,Wireless Markup Langua
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