notes for module 1

To understand the role that computers play in a networking system, consider the Internet. Internet connections are essential for businesses and education. Careful planning is required to build a network that will connect to the Internet. Even for an individual personal computer (PC) to connect to the Internet, some planning and decisions are required. Computer resources must be considered for Internet connection. This includes the type of device that connects the PC to the Internet, such as a network interface card (NIC) or modem. Protocols, or rules, must be configured before a computer can connect to the Internet. Proper selection of a Web browser is also important.
This module covers some of the objectives for the CCNA 640-801, INTRO 640-821, and ICND 640-811 exams.
Students who complete this lesson should be able to perform the following tasks:

Understand the physical connections needed for a computer to connect to the Internet

Recognize the components of a computer

Install and troubleshoot NICs and modems

Configure the set of protocols needed for Internet connection

Use basic procedures to test an Internet connection

Demonstrate a basic ability to use Web browsers and plug-ins

notes

Transistor – Device that amplifies a signal or opens and closes a circuit.

Integrated circuit – Device made of semiconductor material that contains many transistors and performs a specific task.

Resistor – An electrical component that limits or regulates the flow of electrical current in an electronic circuit.

Capacitor – Electronic component that stores energy in the form of an electrostatic field that consists of two conducting metal plates separated by an insulating material.

Connector – The part of a cable that plugs into a port or interface.

Light emitting diode (LED) – Semiconductor device that emits light when a current passes through it.

Printed circuit board (PCB) – A circuit board which has conducting tracks superimposed, or printed, on one or both sides. It may also contain internal signal layers and power and ground planes. Microprocessors, chips and integrated circuits and other electronic components are mounted on the PCB.

CD-ROM drive – A device that can read information from a CD-ROM.

Central processing unit (CPU) – The part of a computer that controls the operation of all the other parts. It gets instructions from memory and decodes them. It performs math and logic operations, and translates and executes instructions.

Floppy disk drive – A computer drive that reads and writes data to a 3.5-inch, circular piece of metal-coated plastic disk. A standard floppy disk can store approximately 1 MB of information.

Hard disk drive – A computer storage device that uses a set of rotating, magnetically coated disks called platters to store data or programs. Hard drives come in different storage capacity sizes.

Microprocessor – A microprocessor is a processor which consists of a purpose-designed silicon chip and is physically very small. The microprocessor utilizes Very Large-Scale Integration (VLSI) circuit technology to integrate computer memory, logic, and control on a single chip. A microprocessor contains a CPU.

Motherboard – The main printed circuit board in a computer. The motherboard contains the bus, the microprocessor, and integrated circuits used for controlling any built-in peripherals such as the keyboard, text and graphics display, serial ports and parallel ports, joystick, and mouse interfaces.

Bus – A collection of wires on the motherboard through which data and timing signals are transmitted from one part of a computer to another.

Random-access memory (RAM) – Also known as read-write memory because new data can be written to it and stored data can be read from it. RAM requires electrical power to maintain data storage. If a computer is turned off or loses power all data stored in RAM is lost.

Read-only memory (ROM) – Computer memory on which data has been prerecorded. Once data has been written onto a ROM chip, it cannot be removed and can only be read.

System unit – The main part of a PC, which includes the chassis, microprocessor, main memory, bus, and ports. The system unit does not include the keyboard, monitor, or any external devices connected to the computer.

Expansion slot – A socket on the motherboard where a circuit board can be inserted to add new capabilities to the computer. Figure shows Peripheral Component Interconnect (PCI) and Accelerated Graphics Port (AGP) expansion slots. PCI is a fast connection for boards such as NICs, internal modems, and video cards. The AGP port provides a high bandwidth connection between the graphics device and the system memory. AGP provides a fast connection for 3-D graphics on computer systems.

Power supply – The component that supplies power to a computer.

The following backplane components are also important:

Backplane – A backplane is an electronic circuit board containing circuitry and sockets into which additional electronic devices on other circuit boards or cards can be plugged; in a computer, generally synonymous with or part of the motherboard.

Network interface card (NIC) – An expansion board inserted into a computer so that the computer can be connected to a network.

Video card – A board that plugs into a PC to give it display capabilities.

Audio card – An expansion board that enables a computer to manipulate and output sounds.

Parallel port – An interface capable of transferring more than one bit simultaneously that is used to connect external devices such as printers.

Serial port – An interface that can be used for serial communication in which only one bit is transmitted at a time.

Mouse port – A port used to connect a mouse to a PC.

USB port – A Universal Serial Bus connector. A USB port connects devices such as a mouse or printer to the computer quickly and easily.

Firewire – A serial bus interface standard offering high-speed communications and isochronous real-time data services.

Power cord – A cord used to connect an electrical device to an electrical outlet that provides power to the device

a web browser:

Contacts a Web server
Requests information
Receives information
Displays the results on the screen

Decimal representation of IP addresses and network masksThis page summarizes the topics discussed in this module.
A connection to a computer network can be broken down into the physical connection, the logical connection, and the applications that interpret the data and display the information. Establishment and maintenance of the physical connection requires knowledge of PC components and peripherals. Connectivity to the Internet requires an adapter card, which may be a modem or a network interface card (NIC).
In the early 1960s modems were introduced to provide connectivity to a central computer. Today, access methods have progressed to services that provide constant, high-speed access.
The logical connection uses standards called protocols. The Transmission Control Protocol/Internet Protocol (TCP/IP) suite is the primary group of protocols used on the Internet. TCP/IP can be configured on a workstation using operating system tools. The ping utility can be used to test connectivity.
A web browser is software that is installed on the PC to gain access to the Internet and local web pages. Occasionally a browser may require plug-in applications. These applications work in conjunction with the browser to launch the program required to view special or proprietary files.
Computers recognize and process data using the binary, or Base 2, numbering system. Often the binary output of a computer is expressed in hexadecimal to make it easier to read. The ablility to convert decimal numbers to binary numbers is valuable when converting dotted decimal IP addresses to machine-readable binary format. Conversion of hexadecimal numbers to binary, and binary numbers to hexadecimal, is a common task when dealing with the configuration register in Cisco routers.
Boolean logic is a binary logic that allows two numbers to be compared and a choice generated based on the two numbers. Two networking operations that use Boolean logic are subnetting and wildcard masking.
The 32-bit binary addresses used on the Internet are referred to as Internet Protocol (IP) addresses.