Chapter 6 Telecommunications & Networking

TCP/IP functions in four layers:

1. Application Layer: enables client application programs to access the other layers, and it defines the protocols that applications use to exchange data. 2. Transport Layer: provides the application layer with communication and packet services. 3. Internet Layer: responsible for addressing, routing, and packaging data packets. 4. Network Interface Layer: places packets on, and receives them from, the network medium, which can be any networking technology.

Three Factors Could Cause Internet Brownout

1. Increasing number of people who work online 2. Soaring popularity of Web sites such as YouTube requiring large amounts of bandwidth 3. Tremendous demand for high-definition television delivered over the Internet

TCP performs three basic functions

1. It manages the movement of data packets between computers by establishing a connection between the computers 2. it sequences the transfer of packets 3. it acknowledges the packets that have been transmitted

Three Basic Functions of the TCP

1. Manages the movement of data packets between computers by establishing a connection between the computers 2. Sequences the transfer of packets 3. Acknowledges the packets that have been transmitted

Ethernet

A common LAN protocol. Many organizations use 100-gigabit Ethernet, where the network provides data transmission speeds of 100 gigabits (100 billion bits) per second.

Electronic Teleconferencing

the use of electronic communication technology that enables two or more people at different locations to hold a conference.

Teleconferencing

the use of electronic communication technology that enables two or more people at different locations to hold a conference.

Packet Switching

the transmission technology that breaks up blocks of data into packets is called packet switching. Each packet carries the information that will help it reach its destination—the sender's IP address, the intended receiver's IP address, the number of packets in the message, and the number of the particular packet within the message. Each packet travels independently across the network and can be routed through different paths in the network. When the packets reach their destination, they are reassembled into the original message.

Internet Assigned Numbers Authority (IANA)

which is in charge of maintaining the DNS root zone. Today, IANA distinguishes the following groups of TLDs:

Telecommuting

A process in which knowledge workers are being called the distributed workforce, or "digital nomads." This group of highly prized workers is now able to work anywhere and anytime.

World Wide Web (WWW)

A system of universally accepted standards for storing, retrieving, formatting, and displaying information via a client/server architecture -Web site -Webmaster -Uniform Resource Locator (URL) -Browsers

Packets

Before data are transmitted over the Internet, they are divided into small, fixed bundles called packets.

Client/Server Computing

Client/server computing links two or more computers in an arrangement in which some machines, called servers, provide computing services for user PCs, called clients.

Connecting Via an Online Service:

Internet Service Provider: is a company that provides Internet connections for a fee. Large ISPs include Comcast (www.comcast.com), AT&T (www.att.com), Time Warner Cable (www.timewarnercable.com), and Verizon (www.verizon.com). Network Access Point: often used by ISPs to connect one another, NAPs are exchange points for Internet traffic. They determine how traffic is routed. NAPs are key components of the Internet backbone. Figure 6.8 displays a schematic of the Internet.

Telepresence

The latest form of videoconferencing which enables participants to seamlessly share data, voice, pictures, graphics, and animation by electronic means.

Internet Backbone

The primary network connections and telecommunications lines that link the nodes made up of a fiber-optic network that is operated primarily by large telecommunications companies.

Internationalized country code top-level domains (IDN ccTLD):

These are ccTLDs in non-Latin character sets (e.g., Arabic or Chinese).

Generic top-level domains (gTLD):

Top-level domains with three or more characters. gTLDs initially consisted of .gov, .edu, .com, .mil, .org, and .net. In late 2000, ICANN introduced .aero, .biz, .coop, .info, .museum, .name, and .pro. In June 2012, ICANN revealed nearly 2,000 applications for new top-level domains.

Country-code top-level domains (ccTLD)

Two letter domains established for countries or territories. For example, de stands for Germany, it for Italy, and ru for Russia.

Portals

a Web-based, personalized gateway to information and knowledge that provides relevant information from different IT systems and the Internet using advanced search and indexing techniques.

Router

a communications processor that routes messages from a LAN to the Internet, across several connected LANs, or across a wide area network such as the Internet.

Search Engine

a computer program that searches for specific information by keywords and then reports the results.

Internet ("the Net")

a global WAN that connects approximately 1 million organizational computer networks in more than 200 countries on all continents, including Antarctica. It has become so widespread that it features in the daily routine of some 3 billion people.

Communication

a major category of network applications related to communication technologies delivered online (e.g., including e-mail, call centers, chat rooms, and voice).

Wide Area Network (WAN)

a network that covers a large geographical area. WANs typically connect multiple LANs. They are generally provided by common carriers such as telephone companies and the international networks of global communications services providers. WANs have large capacity, and they typically combine multiple channels (e.g., fiber-optic cables, microwave, and satellite). The Internet is an example of a WAN.

INTRAnet

a network that uses Internet protocols so that users can take advantage of familiar applications and work habits. Intranets support discovery (easy and inexpensive browsing and search), communication, and collaboration inside an organization.

Communications Channel

a pathway or medium communicating data from one location to another.

Crowdsourcing

a process in which an organization outsources a task to an undefined, generally large group of people in the form of an open call.

Coaxial Cable

a single strand of insulated copper wire. It is much less susceptible to electrical interference, and it can carry much more data than twisted-pair. It is commonly used to carry high-speed data traffic as well as television signals.

World Wide Web

a system of universally accepted standards for storing, retrieving, formatting, and displaying information via a client/server architecture.

Computer Network

a system that connects computers and other devices (e.g., printers) via communications media so that data and information can be transmitted among them.

Peer-to-Peer (P2P) Processing

a type of client/server distributed processing where each computer acts as both a client and a server. Each computer can access (as assigned for security or integrity purposes) all files on all other computers.

Synchronous Collaboration

all team members meet at the same time.

Software-Defined Networks (SDN)

an emerging technology that is becoming increasingly important to help organizations manage their data flows across their enterprise networks. With SDN, decisions controlling how network traffic flows across network devices are managed centrally by software. The software dynamically adjusts data flows to meet business and application needs.

Broadband

based on the Federal Communications Commission (FCC) 2010 definition, broadband is the transmission capacity of a communications medium (discussed late

EXTRAnet

connects parts of the intranets of different organizations.

Local Area Network (LAN)

connects two or more devices in a limited geographical region, usually within the same building, so that every device on the network can communicate with every other device.

Fiber-Optic Cable

consists of thousands of very thin filaments of glass fibers that transmit information via light pulses generated by lasers. The fiber-optic cable is surrounded by cladding, a coating that prevents the light from leaking out of the fiber.

Modem or Modulator-demodulator

converts digital signals to analog signals—a process called modulation—and analog signals to digital signals—a process called demodulation. (The name modem is a contraction of modulator-demodulator.) Dial-up modem Cable modems DSL

Internet Corporation for Assigned Names (ICANN) (www.icann.org):

coordinates these unique addresses throughout the world. Without that coordination, we would not have one global Internet

Internet2

develops and deploys advanced network applications such as remote medical diagnosis, digital libraries, distance education, online simulation, and virtual laboratories. It is designed to be fast, always on, everywhere, natural, intelligent, easy, and trusted. Note that Internet2 is not a separate physical network from the Internet.

Digital Signals

discrete pulses that are either on or off, representing a series of bits (0s and 1s). Th is quality allows digital signals to convey information in a binary form that can be interpreted by computers.

Distributed Processing .

divides processing work among two or more computers which enables computers in different locations to communicate with one another via telecommunications.

Corporate Backbone Networks

high-speed central networks to which multiple smaller networks (such as LANs and smaller WANs) connect.

Internet Protocol (IP)

is responsible for disassembling, delivering, and reassembling the data during transmission.

Communications Media

is the physical media used to send data (e.g., twisted-pair wire, coaxial cable, fiber optic cable, satellite, etc.).

Hypertext

is the underlying concept defining the structure of the World Wide Web. Hypertext is the text displayed on a computer display or other electronic device with references, called hyperlinks, to other text that the reader can immediately access, or where text can be revealed progressively at additional levels of details.

Asynchronous Collaboration

occurs when team members cannot meet at the same time.

Transmission Control Protocol/Internet Protocol (TCP/IP)

the protocol of the Internet. TCP/IP uses a suite of protocols, the main ones being the Transmission Control Protocol (TCP) and the Internet Protocol (IP).

Enterprise Network

organizational interconnected networks consisting of multiple LANs and may also include multiple WAN's.

Distance Learning

refers to any learning situation in which teachers and students do not meet face-to-face.

Bandwidth

refers to the transmission capacity of a network; it is stated in bits per second.

Metasearch Engines

search several engines at once and then integrate the findings to answer users' queries.

Unified Communications:

simplifies and integrates all forms of communications (voice, voice mail, fax, chat, e-mail, instant messaging, short message service, presence (location) services, and videoconferencing) on a common hardware and soft ware platform.

Top-Level Domain (TLD)

the domain at the highest level in the hierarchical Domain Name System of the Internet. The top-level domain names are located in the root zone (rightmost zone) of the name. Management of most TLDs is delegated to responsible organizations by ICANN.

Twisted-Pair Wire

the most prevalent form of communications wiring used for almost all business telephone wiring and As the name suggests, it consists of strands of copper wire twisted in pairs. It is relatively inexpensive to purchase, widely available, and easy to work with.