... wired network interface portãAP functions Wireless communications base stationBridge between the wireless and wired networks 6 Wireless Network Interface Card (continued) 5 Wireless Network ... ofwireless clients and an APãExtended Service Set (ESS)Two or more BSS wireless networks installed in same area –Provides users with uninterrupted mobile access to the network ãAll wireless ... communicate among themselves Wireless Communications Wireless LocalArea Networks 4WLAN ComponentsãMinimal hardware needed for a WLANComputerISP Wireless network interface cardAccess...
... carrier is of a very narrow bandwidth, which means that its data rate is slow. Figure9.10 shows the spectrum for an OFDM transmission. Wireless LocalArea Networks 255Figure 9.10 Detection of OFDM ... target of this group is to enhance the current 802.11 MAC to provide security improve-ments.9.7 SummaryIn this chapter we cover the areaofWirelessLocalArea Networks by focusing on a number of ... requirement for every network, it is an even more Wireless LocalArea Networks 245Figure 9.5 Example of frequency reuse ẵ221IÊ ranfị Ê Slot_time, where i is the number of times the station...
... HomogeneousPlaneWaves 533.1.4 InhomogeneousPlaneWaves 533.1.5 PhysicsofHomogeneousvs.InhomogeneousPlaneWaves 553.2 TheLocalArea 603.2.1 DefinitionofaLocalArea 603.2.2 ScattererProximity 603.2.3 AWidebandPlaneWave ... 3 discusses the basic form that a stochastic localarea channel model musttake. Great care is taken in defining a localarea and a stochastic localarea channel, clearlystating the assumptions ... ApplicationstoWirelessTechnology 187vii THEORY OF STOCHASTIC LOCALAREA CHANNELMODELING FOR WIRELESS COMMUNICATIONSbyGregory D. DurginFinal Dissertation submitted to the Faculty of theVirginia Polytechnic...
... using SIRãThen they shift to FIR speed Wireless CommunicationsLow Rate Wireless Personal Area Networks 2ObjectivesãDescribe a wireless personal areanetwork (WPAN)ãList the different WPAN ... and ZigBee workãDescribe the security features of low-rate WPAN technology 3What is a WPAN?ã Wireless personal areanetwork (WPAN)Group of technologies that are designed for short-range ... SecurityãSecurity should be of little concern with WPANsãOne of the most serious concerns is social engineeringãDesigning security in WPANsMuch more difficult task than in other networking technologiesãPublic...
... include a set of fields that are present in the same order in every frame Wireless# Guide to Wireless Communications 15802.15.3 Network Topology (continued) Wireless# Guide to Wireless Communications ... corrected–Also called error correction (FEC) Wireless# Guide to Wireless Communications 26Mesh Networking (802.15.5) (continued) Wireless# Guide to Wireless Communications 28How UWB WorksãUWB ... division multiplexing (OFDM)ãCommonly referred to as MB-OFDMãFrequency band is divided into five groups containing a total of 14 frequency bands Wireless# Guide to Wireless Communications...
... have a radius of up to 35 miles (56 kilometers) 2ObjectivesãExplain why wireless metropolitan area networks (WMANs) are neededãDescribe the components and modes of operation of a WMANãList ... a WMAN?ã Wireless metropolitan area networks (WMANs)Provide wireless connectivity across a substantial geographical area such as a large cityãWMANs primary goalsExtend wired networks beyond ... Service (MMDS) (continued)ã Advantages of MMDSSignal strengthCell sizeCostãDisadvantages of MMDS–Physical limitations–Frequency sharing–Security–Availability of the technology 21SummaryãWMANs...
... (2.5G)Interim step between 2G and 3G–Operates at a maximum speed of 384 Kbps–2.5G networks are packet-switched Advantages of packet switchingãMuch more efficientCan handle more transmissions ... for a stationary userã3G network technologiesCDMA2000 1xEVDOãFor 2.5G CDMA2000 1xRTT networks 25Binary Runtime Environment for Wireless (BREW)ãBREW is a thin software environmentVery ... (continued)ãShort Message Services (SMS)One of the most widely used applications–Allows for the delivery of short, text-based messages between wireless devicesãMessages are limited to about...
... nhất được nhận dạng bởi thiết bị hai đầu.5.4 CÔNG NGHỆ VLAN:VLAN là viết tắt của Virtual LocalAreaNetwork hay còn gọi là mạng LAN ảo. Một VLAN được định nghĩa là một nhóm logic các thiết ... hình native VLAN thì phải cấu hình ở giao diện vật lý.CHƯƠNG IILÝ THUYẾT VỀ MẠNGWAN (WIDE AREA NETWORK) I. KHÁI NIỆM :Là mạng được thiết lập để liên kết các máy tính của hai hay nhiều khu ... trí rất xa nhau, ví dụ như những quốc gia khác nhau, thì khi đó ta có mạng diện rộng WAN(Wide Area Network) TrangNGUYỄN ĐÌNH CÔNG – 36CLTH2929 V./. CÁC CÔNG NGHỆ MẠNG LAN :5.1. CÔNG NGHỆ CHUYỂN...
... Trunking: Off, Encapsulation type: UnknownSwitchA#show trunk bDISL state: Off, Trunking: Off, Encapsulation type: UnknownSwitchA#Note that "Off" is the default DISL state. "Off" ... Page 1 of 17http://www.certificationzone.com/studyguides /?Issue=34&IssueDate=04-01-2001&CP= 11/06/01Date of Issue: 04-01-2001 CCNA Layer 2 Switching - Virtual Local Area NetworksLab ... Enterprise edition software. The Cisco IOS software CLI is not available if the switch has been configured with the Standard edition software.While it is possible to complete most of this lab using...
... installation of Ethernet networks, a change wasmade to the network topology.Networks were converted fromcoaxial cable to twisted pair cabling by introducing a new deviceinto the network. That ... an IP network orsubnet.In most practical networks, all devices in a small business or enterprise network are not located on the sameEthernet network broadcast domain.We separate the networks ... the history of Ethernet, the virtual LAN is a recent addition. The VLAN was introduced to solve a number of networking issues. In this whitepaper you will learn about the evolution of Ethernet,...
... wave of an Ethernet signal is made of many different sine waves,each important to creating the shape of the square wave.Ethernet Signal PreservationIn Factory-Terminated Patch Cords for LocalArea ... wave.Figure 1: The square wave of an Ethernet signal.Figure 3: Sine waves of varying frequencies. The philosophy of the TrueNet system is to eliminate the root causes of poor throughput in structured ... square wave is made up of the sum of many sine waves. If anything should happen tothe energy in one or more of those sine waves as they traveldown the wire, the shape of the square wave can...