Computer Science. The English Language Perspective - Беликова (1176925), страница 25
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The most basic tool is HTmL, which has undergoneperiodic revisions and expansions.3. Many sites include several different navigation systemsincluding buttons, links, and perhaps menus.4. The emphasis will be on providing speedy access to theinformation people need to do their job, and in keepinginformation accurate and up to date.5. These programs also provide “themes” that help keepthe visual and textual elements of the page consistent.6.
Page designers must also make sure that the graphicsthey are using are created in-house, are public domain,or are used by permission.7. Although the Web is a new medium, much of thetraditional typographic wisdom still applies. Just asmany people who first encountered the variety ofWindows or Macintosh fonts in the 1980s filled theirdocuments with a variety of often bizarre typefaces,beginning Web page designers sometimes choose fontsthat they think are “edgy” or cool, but may be hard toread—especially when shown against a purplebackground!1462. Answer the following questions.1.2.3.4.What are the basic skills for designing web pages?What can help to create with web design?What should technologies web designers know?What can be said about the line between Web pagedesign and other web services?3.
Translate into English:Web-дизайн – это не только внешнее оформлениесайта. На нем должны быть грамотно расположеныэлементы, текст должен легко читаться, и самое главное –он должен быть удобным для пользователя. Размещениеинформации на сайте должно быть четко продумано иоформлено соответствующим образом. Веб-дизайнердолжен уметь не только хорошо рисовать и правильноподбирать цветовую гамму, но и смотреть на свой шедеврглазами посетителя.Разработка веб-приложений — это общий термин дляпроцесса создания веб-страниц или сайтов.
Веб-страницысоздаются с использованием HTML, CSS и JavaScript. Этистраницы могут содержать простой текст и графику,напоминая собой статичный документ. Страницы такжемогут быть интерактивными или отображать меняющуюсяинформацию. Создавать интерактивные страницы немногосложнее, но они позволяют создавать веб-сайты с богатымсодержимым.
Сегодня большинство страниц интерактивныи предоставляют современные интерактивные услуги,такие как корзины интернет-магазинов, динамическаявизуализация и даже сложные социальные сети.4. Give the summary of the text using the key terms.147INTERNET PROTOCOLSRead the following words and word combinations and usethem for understanding and translation of the text:to communicate across - общаться черезscope - сфера, уровеньto facilitate - облегчатьcorresponding - соответствующийdissimilar - непохожие,различныеto span - охватыватьgoal - цельto consist of - состоять изflow - потокreference model - эталонная модельto overflow internal buffers – переполнить буферы обменаbenefits - преимуществаfull-duplex operation - спаренный режим работыto be acknowledged - быть признаннымThe Internet protocols are the world's most popular opensystem (nonproprietary) protocol suite because they can beused to communicate across any set of interconnected networksand are equally well suited for LAN and WANcommunications.
The Internet protocols consist of a suite ofcommunication protocols, of which the two best known are theTransmission Control Protocol (TCP) and the Internet Protocol(IP). The Internet protocol suite not only includes lower-layerprotocols (such as TCP and IP), but it also specifies commonapplications such as electronic mail, terminal emulation, andfile transfer.Internet protocols were first developed in the mid-1970s, whenthe Defense Advanced Research Projects Agency (DARPA)became interested in establishing a packet-switched networkthat would facilitate communication between dissimilarcomputer systems at research institutions.
With the goal of148heterogeneous connectivity in mind, DARPA funded researchby Stanford University and Bolt, Beranek, and Newman (BBN).The result of this development effort was the Internet protocolsuite, completed in the late 1970s.TCP/IP later was included with Berkeley Software Distribution(BSD) UNIX and has since become the foundation on which theInternet and the World Wide Web (WWW) are based.Documentation of the Internet protocols (including new orrevised protocols) and policies are specified in technical reportscalled Request For Comments (RFCs), which are published andthen reviewed and analyzed by the Internet community.Protocol refinements are published in the new RFCs.
Internetprotocols span the complete range of OSI model layers maps,many of the protocols of the Internet protocol suite and theircorresponding OSI layers.Internet Protocol (IP)The Internet Protocol (IP) is a network-layer (Layer 3) protocolthat contains addressing information and some controlinformation that enables packets to be routed. IP is documentedin RFC 791 and is the primary network-layer protocol in theInternet protocol suite.
Along with the Transmission ControlProtocol (TCP), IP represents the heart of the Internet protocols.IP has two primary responsibilities: providing connectionless,best-effort delivery of datagrams through an internetwork; andproviding fragmentation and reassembly of datagrams tosupport data links with different maximum-transmission unit(MTU) sizes.Transmission Control Protocol (TCP)The TCP provides reliable transmission of data in an IPenvironment.
TCP corresponds to the transport layer (Layer 4)of the OSI reference model. Among the services TCP providesare stream data transfer, reliability, efficient flow control, fullduplex operation, and multiplexing.149With stream data transfer, TCP delivers an unstructured streamof bytes identified by sequence numbers. This service benefitsapplications because they do not have to chop data into blocksbefore handing it off to TCP. Instead, TCP groups bytes intosegments and passes them to IP for delivery.TCP offers reliability by providing connection-oriented, end-toend reliable packet delivery through an internetwork. It doesthis by sequencing bytes with a forwarding acknowledgmentnumber that indicates to the destination the next byte thesource expects to receive.
Bytes not acknowledged within aspecified time period are retransmitted. The reliabilitymechanism of TCP allows devices to deal with lost, delayed,duplicate, or misread packets. A time-out mechanism allowsdevices to detect lost packets and request retransmission.TCP offers efficient flow control, which means that, whensending acknowledgments back to the source, the receivingTCP process indicates the highest sequence number it canreceive without overflowing its internal buffers. Full-duplexoperation means that TCP processes can both send and receiveat the same time.Finally, TCP's multiplexing means that numerous simultaneousupper-layer conversations can be multiplexed over a singleconnection.Notes:LAN - Локальная вычислительная сеть (ЛВС, локальнаясеть, сленг.
локалка; англ. Local Area Network, LAN) —компьютерная сеть, покрывающая обычно относительнонебольшую территорию или небольшую группу зданий(дом, офис, фирму, институт)WAN - Wide Area Network (WAN) - Глобальнаявычислительная сеть охватывает целые области, страны идаже континенты.TCP - Transmission Control Protocol (TCP) (протоколуправления передачей) — один из основных протоколов150передачи данных Интернета, предназначенный дляуправления передачей данных в сетях и подсетях TCP/IP.IP - Internet Protocol (IP, досл.
«межсетевой протокол») —маршрутизируемый протокол сетевого уровня стекаTCP/IP. Именно IP стал тем протоколом, которыйобъединил отдельные компьютерные сети во всемирнуюсеть Интернет.OSI - Сетевая модель OSI (англ. open systems interconnectionbasic reference model) — базовая эталонная модельвзаимодействия открытых системDARPA (Defense Advanced Research Projects Agency) Управление передовых оборонных исследовательскихпроектов Министерства обороны США, целью которогоявляется сохранение технологического превосходствавооруженных сил США, предотвращение внезапного дляСША появления новых технических средств вооруженнойборьбы, поддержка прорывных исследований, преодолениеразрыва между фундаментальными исследованиями и ихприменением в военной сфере.Assignments1.
Translate the sentences from the text into Russian paying inwriting paying attention to the underlined words andphrases:1. The Internet protocols consist of a suite ofcommunication protocols, of which the two best knownare the Transmission Control Protocol (TCP) and theInternet Protocol (IP).2. The Internet protocol suite not only includes lower-layerprotocols (such as TCP and IP), but it also specifiescommon applications such as electronic mail, terminalemulation, and file transfer.1513.
With stream data transfer, TCP delivers an unstructuredstream of bytes identified by sequence numbers.4. This service benefits applications because they do nothave to chop data into blocks before handing it off toTCP. Instead, TCP groups bytes into segments andpasses them to IP for delivery.5. TCP offers reliability by providing connection-oriented,end-to-end reliable packet delivery through aninternetwork.6.
It does this by sequencing bytes with a forwardingacknowledgment number that indicates to thedestination the next byte the source expects to receive.Bytes not acknowledged within a specified time periodare retransmitted.2. Answer the following questions.1.2.3.4.5.When were the Internet protocols used for the first time?What does the Internet Protocol contain?What are the major responsibilities of IP?What services does TCP provide?What is the general use of the Internet Protocols?3.
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