wide area networks by patrick regan

... 9 Wireless Local Area Networks 9.1 Introduction The growth of Wireless Local Area Network (WLANs) commenced in the mid-1980s and was triggered by the US Federal Communications ... provide security improvements 9.7 Summary In this chapter we cover the area of Wireless Local Area Networks by focusing on a number of issues: † WLAN topologies The two types of wireless ... supported by both technologies and is thus characterized by a moderate cost However, the situation reverses when noise and interference are taken into account From Wireless Local Area Networks

Ngày tải lên: 29/09/2013, 21:20

... 95134-1706 USA Enterprise Branch Wide Area Application Services Design Guide (Version 1.1) This document discusses design and deployment considerations in deploying wide area application services (WAAS) ... Enterprise Branch Wide Area Application Services Design Guide (Version 1.1) OL-12945-01 Introduction • Use a standby interface to protect against network link and switch failure. Standby interface ... optimization, particularly using WAAS. 7 Enterprise Branch Wide Area Application Services Design Guide (Version 1.1) OL-12945-01 Introduction Figure 1 Wide Area Application Services (WAAS) Mechanisms The

Ngày tải lên: 10/12/2013, 16:15

... simplify the installation of Ethernet networks, a change was made to the network topology . Networks were converted from coaxial cable to twisted pair cabling by introducing a new device into the ... complex switching architectures. Cisco pioneered the naming of theses complex networks by defining the location of the switch by function into a hierarchy. Clients were directly attached to “access” ... boundary between the two VLANs on the switch cannot be bypassed by Ethernet. Figure 6. Simple VLANs in a 24 Port Switch This also creates two IP networks or subnets. For traffic to flow between the

Ngày tải lên: 17/01/2014, 06:20

... CONSIDERATIONS FOR STORAGE AREA NETWORKS Security Considerations for Storage Area Networks Colleen Rhodes East Carolina University Trang 2Abstract In this paper I will describe Storage Area Networks (SANs) ... securing a Storage Area Network by using best practices in setting up a SAN as well as securing the data on a day-to-day basis Trang 3Security Considerations for Storage Area Networks What is ... Storage area networks also separate storage traffic from general network traffic Biran, O., Meth, K., Sarkar, P., Satran, J & Voruganti, K (2003, Benefits section, para 3) report, In a storage area

Ngày tải lên: 14/02/2014, 16:20

... Working Paper No. 383 Contagion in financial networks Prasanna Gai and Sujit Kapadia March 2010 Working Paper No. 383 Contagion in financial networks Prasanna Gai (1) and Sujit Kapadia (2) Abstract This ... analytical model of contagion in financial networks with arbitrary structure. We explore how the probability and potential impact of contagion is influenced by aggregate and idiosyncratic shocks, ... connected system, the counterparty losses of a failing institution can be more widely dispersed to, and absorbed by, other entities. So increased connectivity and risk sharing may lower the probability

Ngày tải lên: 17/02/2014, 21:20

... matter” Distribution of private keys could be done by physically entering them into a keypad at the device, or by using public key cryptography, or by some other means In addition to the issue of ... modules to provide for a wide spectrum of data sensitivity and a diversity of application environments Four security levels are specified for each of 11 requirement areas These 11 areas are sections ... traverse a public network is sent by a tunneling mechanism A device called a “BACnet/Internet Protocol Packet-Assembler-Disassembler” (B/IP PAD) exists on both networks, keeps track of all other

Ngày tải lên: 14/03/2014, 22:20

... processing step by replacing the collection in the solution by the collection being considered, divided by the time increase that would result from the substitution The algorithm begins by considering ... of wide-area distributed database systems differ dramatically from those of local-area network systems In a wide-area network (WAN) configuration, individual sites usually report to different system ... Mariposa networks Similarly, a server can join a Mariposa system at any time by buying objects from other sites, advertising its services and then bidding on queries It can leave Mariposa by selling

Ngày tải lên: 23/03/2014, 12:20

... processing step by replacing the collection in the Trang 12solution by the collection being considered, divided by the time increase that would result from the tution.substi-The algorithm begins by considering ... Mariposa networks Similarly, aserver can join a Mariposa system at any time by buying objects from other sites, advertising its servicesand then bidding on queries It can leave Mariposa by selling ... rea-sonably uniform interconnect tends to mask performance problems caused by suboptimal data allocation In a wide-area network environment, these assumptions are much less plausible For example,

Ngày tải lên: 28/04/2014, 13:38

... body area networks Jean-Michel Dricot1*, Stéphane Van Roy1, Gianluigi Ferrari2, François Horlin1and Philippe De Doncker1 Abstract Personal area networks and, more specifically, body area networks ... sensors have fostered the research in the field of body-centric networks, also referred to as body area networks (BANs) [1-4] In these networks, a set of nodes (called sensors) is deployed on the ... is supported by the observations in [[22], p 278] and [21,23], where it is shown that the traffic gener-ated by nodes using a slotted random access MAC proto-col can be modeled by means of a

Ngày tải lên: 20/06/2014, 22:20

... TCP window size, TXOP Exchange, Wireless local area networks 1 Introduction In offices, homes, and public spaces, IEEE 802.11 wire-less local area networks (WLANs) has been extensively used to ... RFC1323, and Keepalive probes; maximum segment size was 1,500 bytes; send buffer size was 65,000 bytes; receive buffer size was 65,000 bytes; wired bottlenecklink bandwidth was 10 Mbps, while other ... RFC1323, and Keepalive probes; maximum segment size was 1,500, bytes; send buffer size was 65,000 bytes; receive buffer size was 65,000, bytes; Access network is IEEE 802.11a WLAN with physical transmission

Ngày tải lên: 21/06/2014, 01:20

... time synchronization is a paramount service for wireless sensor networks (WSNs) constituted by multiple interconnected body area networks (BANs) We propose a novel approach to securely and efficiently ... results are based on computations 1 Introduction Body area networks (BANs) are receiving a lot of attention connected sensors nodes worn by or implated to a human body Each BAN includes a controller ... time needed for the sender to transmit the message bit by bit at the physical layer This time can be easily calculated by the receiver by knowing the length in bits of the message and the radio

Ngày tải lên: 21/06/2014, 05:20

... dicegame by real-time strategic information delivered to the usertriggered by his gestures and game state Another applicationmay turn a fitness parkour into an interactive social challenge by comparing ... TitanNodes is 24 bytes, as it can easily be fitted with 5 bytes headerinto a TinyOS active message The active message is used to transmit data over wireless links and offers 29 bytes ofpayload ... microcontroller is determined and multiplied by the power consumption difference from active to standby mode (ii) Sensor Cost C s(t, v) The cost of using sensor s required by servicet on node v to collect

Ngày tải lên: 21/06/2014, 07:20

... al., “Cooperative communications in ultra-wideband wireless body area networks: channel modeling and system diversity analysis,” IEEE Journal on Selected Areas in Communications, vol 27, no 1, Article ... medium, provided the original work is properly cited Ultrawideband (UWB) communication is a promising technology for wireless body area networks (BANs), especially for applications that require ... theorem, with an ultra-wide bandwidth, high data rate can be achieved with low transmitted power in UWB Power consumption is also a critical requirement for body area networks, as patients may

Ngày tải lên: 21/06/2014, 07:20

... of cells to changing endogenous or exogenous conditions is governed by intricate networks of gene regulations including those by, most notably, transcription factors (TFs) [1] Understanding how ... proposed to infer the transcriptional regulation by TFs including, mostly notably, ordinary differential equations, (probabilistic) Boolean networks, Bayesian networks, information theory, and association ... 538919, 18 pages doi:10.1155/2010/538919 Research Article Uncovering Transcriptional Regulatory Networks by Sparse Bayesian Factor Model Jia Meng,1 Jianqiu (Michelle) Zhang,1 Yuan (Alan) Qi,2 Yidong

Ngày tải lên: 21/06/2014, 16:20

... wireless regional area networks (WRANs), wireless wide area networks (WWANs), wireless metropolitan area networks (WMANs), wireless local area networks (WLANs), and wireless personal area networks (WPANs) ... cited The performance of wireless networks is affected by channel conditions Link Adaptation techniques have been proposed to improve the degraded network performance by adjusting the design parameters, ... wireless networks possess many advantages against its wired counterpart, for example, capable of device mobility, simple installation, and ease of deployment Depending on the coverage, wireless networks

Ngày tải lên: 21/06/2014, 17:20

... implanted wireless sensor devices are hot research area. A specialized field called the body area networks (BAN) has emerged to support this area. Managing and controlling such a network is ... (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. A power efficient MAC protocol for wireless body area networks ... devices. This has helped expand the application area for sensor networks [1]. Healthcare is one of the major fields employing sensor devices and networks. The applications [2, 3] include both

Ngày tải lên: 21/06/2014, 17:20

... 8-PSK – CDMA2000 1xRTT • Operates on two 1.25 MHz -wide frequency channels • Supports 144 Kbps packet data transmission 2 Objectives • Describe wireless wide area networks (WWANs) and how they are used • Describe ... networks – Watch television or on-demand movies – Take and transmit pictures and short movies – Locate family members and employees using GPS 24 Java • Java programming language – Developed by ... pager, satellite telephone, and location services 41 Summary • In cellular telephone networks, the coverage area is divided into sections called cells • Cellular technology generations – First...

Ngày tải lên: 13/09/2012, 10:52

... network edge Potentially discarded by Weighted Random Early Detection (WRED) (congestion mgmt) Assigned to the appropriate outgoing queue Scheduled for transmission by CBWFQ and sent out interface Classify ... on. CAR can also be used to police precedence bits set externally to the network either by the customer or by a downstream service provider. Thus the network can decide to either accept or override ... the level of congestion Generic Traffic Shaping (GTS) shapes traffic by reducing outbound traffic flow to avoid congestion by constraining traffic to a particular bit rate using the token bucket...

Ngày tải lên: 11/12/2013, 14:15

... coordinate ToS byte (DSCP/IP Precedence) markings and bandwidth allocation. Ta b l e 2 QoS Configuration Options Shaping by Port Shaping by Logical Interface Shaping by Branch Shaping by VLAN Shaping ... and Wide Area Networks OL-14760-01 Design Considerations • Use of EIGRP stub areas eliminates queries to spoke routers. • OSPF must periodically synchronize router databases within an area, ... each See by class/VLAN VLAN per branch with one shaper per class See Scalability and Performance Results, page 40 20 Ethernet Access for Next Generation Metro and Wide Area Networks OL-14760-01 ...

Ngày tải lên: 21/12/2013, 06:15

... shift to FIR speed Wireless Communications Low Rate Wireless Personal Area Networks 2 Objectives • Describe a wireless personal area network (WPAN) • List the different WPAN standards and their ... networking technologies • Public key infrastructure (PKI) – Unique security code, or key, provided by a certificate authority • Certificate authority – Private company that verifies the authenticity ... is a wireless technology that uses short- range radio frequency (RF) transmissions – Supported by over 2,500 hardware and software vendors 6 Infrared WPANs (IrDA) (continued) 15 Bluetooth Link...

Ngày tải lên: 13/09/2012, 10:52