[ Pobierz całość w formacie PDF ]
.The largest privatelyyou insert a new card, the BIOS performs anheld media company on the Internet, pro-auto-configuration sequence enabling theviding online news to corporations.Thenew card with appropriate settings.PointCast broadcast receives more thanNew PCs with flash BIOS will be easy to up-120 million hits a day and offers access to agrade so that they can take advantage ofcollection of more than 600 leading busi-PnP; older systems with ROM-based BIOSness sources.will need a hardware change before theyUnlike the World Wide Web and other In-can take full advantage of PnP.ternet applications, PointCast uses serverSee also Peripheral Component Intercon-push technology, in which the server auto-nect local bus; Plug and Pray.matically sends new data to a client withouta specific request from that client.Plug and Pray What most of us do whenour Plug-and-Play systems do not workFor more information on PointCast, seeautomatically.www.pointcast.com.plug-compatible Any hardware devicepoint-to-point link A direct connectiondesigned to work in exactly the same waybetween two, and only two, locations oras a device manufactured by a differentnodes.company.For example, all external serialPoint-to-Point Protocol Abbreviateddevices are plug-compatible, because youPPP.A TCP/IP protocol used to transmit IPcan replace one with another withoutdatagrams over serial lines and dial-up tele-changing the cabling or connector.phone point-to-point connections.See also pin-compatible.PPP allows a PC to establish a temporary di-plug-in A small program you can link in rect connection to the Internet via modemto your Web browser to add a special capa- and appear to the host system as if it werebility not originally present or to recognize an Ethernet port on the host s network.303Copyright © 2000 SYBEX Inc., Alameda, CA.www.sybex.com2461book Page 304 Thursday, May 4, 2000 11:59 AMPoint-to-Point Tunneling ProtocolPPP provides router-to-router, host-to- transmit or pass the token to the nextrouter, and host-to-host connections and device.also provides an automatic method of as-polymorphic virus A form of virus thatsigning an IP address so that mobile userscan change its appearance to avoid detec-can connect to the network at any point.tion.The virus encrypts itself using a specialSee also PPP Multilink; Point-to-Pointformula each time an infection occurs.Tunneling Protocol; Serial Line InternetVirus-detecting software uses special scan-Protocol.ning techniques to find and remove poly-morphic viruses.Point-to-Point Tunneling ProtocolSee also boot sector virus; file-infecting vi-Abbreviated PPTP.A proprietary network-rus; macro virus; multipart virus; stealthing protocol proposed by Microsoft thatvirus, vaccine; virus.supports virtual private networks, allowingremote users to access Windows NT ServerPOP See point of presence; Post Officesystems across the Internet without compro-Protocol.mising security.PPTP allows corporations toport 1.To move a program or an oper-use public networks rather than leasing itsating system from one hardware platformown lines for wide area communications.to another.For example, Windows NTSee also encapsulation; Layer 2 Tunnelingportability refers to the fact that the sameProtocol; PPP Multilink; tunneling.operating system can run on both Intel andreduced instruction set computing (RISC)point of presence Abbreviated POP.Aarchitectures.connection to the telephone company or to2.The point at which a communicationslong-distance carrier services.circuit terminates at a network, serial, orpolling A method of controlling theparallel interface card, usually identified bytransmission sequence of devices on aa specific port number or name.shared circuit or multi-drop line by sending3.A number used to identify a connectionan inquiry to each device asking if it wantspoint to a specific Internet protocol.to transmit.If a device has data to send, itSee also portable; port number.sends back an acknowledgment, and thetransmission begins.Three methods are inportability The ability to transfer an ap-common use:plication or operating system from one ven-Roll-call A master station uses a pollingdor s hardware to another, quickly andlist to locate the next node to poll.easily, without rewriting the software andwithout affecting its performance.Hub A node polls the next node insequence.This can be achieved in several ways:Token-passing A token is passed to the Write the program in a portable language,next node in sequence.This node can such as C, C++, or Java.304Copyright © 2000 SYBEX Inc., Alameda, CA.www.sybex.com2461book Page 305 Thursday, May 4, 2000 11:59 AMport numberUse only standard programming language Portable Document Format Abbrevi-features.ated PDF.A file format standard developedby Adobe Systems and others for use in elec-Use only standard libraries.tronic documents.A file in this format usu-Don t make assumptions about word sizeally has the filename extension of.PDF.or byte ordering.Portable Operating System InterfaceUse layers of software to distance the ap-Abbreviated POSIX.A collection of IEEEplication from operating system or hard-standards that defines a complete set of por-ware dependencies.table operating system services.POSIX isportable Describes the degree to which abased on Unix services, but it can be imple-program can be moved easily to differentmented by many other operating systems.computing environments with a minimumEach of the standards defines a specific as-number of changes [ Pobierz caÅ‚ość w formacie PDF ]