Network TOPOLOGY

Network TOPOLOGY

The physical layout of computers which describes that, how they are connected arranged, managed, and flow of data from one host to another. There are different types of topology

1) Physical topology

2) Logical topology

1) Physical topology

It describes the physical structure of the cable connected to the network computer.

2) Logical topology

It describes the signal takes as they flow though the network.

Physical topology is further divided into 5 parts.

1.       Star topology

2.       Bus topology

3.       Mesh topology

4.       Ring topology

5.       Wireless topology

Video Ports

Standard cathode ray tube (CRT) monitors and many projectors connect to your PC using a 15-pin D-sub miniature connector arranged in three rows of five pins each. The corresponding video port on the PC, accommodates only that connector. No other port on your PC looks like this one. Many flat-panel liquid crystal display (LCD) monitors and some projectors use a specially keyed, 24-pin Digital Visual Interface (DVI) connector

that plugs into a DVI port on the back of your video adapter card, DVI comes in several varieties, such as analog, DVI-A, and digital, DVI-D

Note: Thin-film transistor the most common LCD monitors use a technology called thin

Many techs erroneously refer to all LCD monitors as TFTs.

The Mouse Port

Like keyboards, mice come in an array of sizes and shapes, and they use a variety of connectors to attach to the PC. All mice enable you to manipulate the Operating system (OS) and applications.

Traditionally, mice plugged into one of the serial ports on the back of the PC, but most motherboards today have a dedicated mini-DIN mouse port. Aside from color, the green mouse port appears identical to the purple PS/2 keyboard port, but they’re not interchangeable.

You can plug a PS/2 mouse connector into a PS/2 keyboard port, and vice versa, but they won’t work. Mice go into mouse ports—keyboards go into keyboard ports. Some portable computers have a single black or gray mini-DIN port that can handle both a mouse and a keyboard (though obviously not at the same time!)

Single Standard Function Ports

Standard Single-Function Ports

Every PC sports several single-function ports for connecting peripherals such as keyboards, monitors, and the like. With only a couple of exceptions, these standard ports support only a single type of device

The Keyboard Port

Keyboards come in a variety of styles, from the plain-Jane, rectangular typewriter substitute to the exotically curved, multi-function gadget that’s bristling with special function hot keys

and equipped with ports of its own. Regardless of their appearance, however, all keyboards enable you to do one thing—enter commands into your PC. Modern PCs have a purple 6-pin mini-DIN (commonly called a PS/2 connector) port . The mini-DIN port is keyed so you can insert the keyboard connector only one way.

What Do You Mean By Ports And Connector? How Many Types Of ports And Connector Are There.

What Do You Mean By Ports And Connector?

A port is a socket on the outside of the system unit that is connected to an expansion board on the inside of the system unit. A port allow connecting a peripheral devices such as a monitor, printer, or modem, so that it can communicate with the computer system. Ports and connector are divided into three parts and they are:-

1. Legacy Multifunction Port
2. Single Standard Function Port
3. Modern Multifunction Port

1. Legacy Multifunction Ports

Every cable has a connector at the end that plugs into a corresponding ports on a PC. Connector carry data and sometimes power between devices attached to the PC. Ports are the interface, the "doorways"  used to connect the devices to the PC.Connectors and ports can be either male or female, defined as having pins or sockets,respectively.
Let’s start with the two ancient multifunction ports that linger on most modern PCs: serial ports and parallel ports.Serial and parallel ports have a slight D shape, which allows only one proper way to insert a plug into the socket and makes it easier to remember what they’re called. Technically, they’re known as D-sub or D-subminiature connectors, but most techs call them DB.

Serial Ports
Serial ports come in 9-pin and 25 varieties . Of the two, the 9 (five pins on the top row, four on the bottom) variety is much more common,n although even those are rapidly disappearing from modern PCs. Serial ports transfer data 1 bit (the smallest unit of data in the PC world) at a time, with a maximum throughput speed of 115Kbps.Devices that connected to the PC via the serial port included mice, external modems, label printers, personal digitalassistants (PDAs), and digital cameras.

Parallel Ports

Parallel ports are the 25-pin (13 on the top row, 12 on the bottom) female ports on the back of older PCs, as shown in. Folks often incorrectly refer to parallel ports simply as “printer ports,” but many other devices have used parallel ports, such as external CD ROM drives, Zip drives, and scanners.
Through this port, the data transimission rate is 1Byte at the speed of 150Kbps. It can transfer the data in higher speed as compare to serial port.

Types Of Motherboard

Types Of Motherboard

There are diffrent types of motherboard and thery are:-

1. XT-  E xtended Technology
2. ATX- Advanced Technology
3. Baby At- BabyAdvanced Technology
4. ATX- Advanced Technology Extended
5. BTX- BalanceTechnology Extended

 XT- X tended Technology

Xt stands for Extended technology. This is old types of motherboard means old model of motherboard which is not not used nowadays. In this mother we can found old types of processor socket LIF (Low Insertion Force) sockets, ram slots DIMMs( Dual inline Memory Module) and ISA (Industry Standards Architecture) slots, 12pin Power Connector and no any external  ports.
They have slot type processors, DIMMs memory modules, ISA slots for add-on card, and no ports. There are connectors and add-on cards for ports.
Eg: Pentium-I, Pentium -MMX, Pentium -II and Pentium-II Processors.

 AT Motherboards:

AT stands for Advanced Technology.
In Advanced Technology of Motherboards we can see PGA (Pin Grid Array) Socket, SD Ram slots, 20pin power connector from SMPS ( switch mode power supply) to motherboard, PCI slots and ISA slots.
we find the above components which is found in  AT motherboards.

Eg: Pentium-III Processors

 Baby AT Motherboards:

Baby AT Motherboards is the combination of both XT and AT.
This is little bit changes each other because it has got both slot type processor sockets and PGA processor sockets, while, AT motherboard  have PGA socket And XTotherboard have Slot types of processer socket, SD Ram slots and DDR Ram slots can be found in this motherboard, PCI slots and ISA slots, 12 Pin power connector and 20Pin power connector and Ports.

Eg: Pentium-III and Pentium-IV

ATX Motherboard

ATX motherboards stands for Advanced Technology eXtended which  have a central Northbridge chip encircled by the CPU, RAM, drive, and power connections; expansion slots; and connections for
external devices.ATX motherboards use mini-DIN (PS/2) connectors for the keyboard and mouse, and most have integrated USB ports. Many also feature onboard modem and NIC ports, FireWire ports, sound, and video. ATX motherboards dominate the PC market. Two popular variations of the ATX form factor are microATX and FlexATX. These use the same power connections and have the same basic layout as ATX but are scaled to fit in to much smaller ATX cases. Full-sized ATX motherboards will not fit into microATX or FlexATX cases, although most full sized cases support the smaller motherboards.

The power supply connector from the smps to motherboard is 20pin or 24 pin.

BTX Motherboard

BTX stands for Balance technology Extended. Fast CPUs and powerful graphics cards in today’s PCs create. phenomenal amounts of heat, which motivated the PC industry to create the “coolest” form factor used today -the Balanced Technology eXtended (BTX) form factor. BTX defines three subtypes: standard BTX, microBTX, and picoBTX, designed to replace ATX, microATX, and FlexATX,
respectively. At first glance, BTX looks like ATX, but notice that the I/O ports and the expansion slots have switched sides. Everything in the BTX standard is designed to improve cooling. BTX cases vent in cool air from the front and vent out warm air in the back. CPUs are moved to the front of the motherboard so they benefit from the cool air entering the front of the case. BTX defines a special heat sink and fan assembly called the thermal unit. The thermal unit’s fan blows the hot CPU air directly out the back of the case, as opposed to the ATX method of just blowing the air into the case and letting the power supply and case fans pull air out. The BTX standard offers better cooling than ATX, but the PC industry tends to take its time when making big changes like moving to a new form factor. As a result, BTX has not yet made much of an impact in the industry, and BTX motherboards, cases, and thermal units are still fairly rare.

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Motherboard Form FactorAnd Internall And external Connectors

2) Motherboard Form Factor

Motherboards come into different  form factors,XT, AT, Baby AT, ATX or BTX, plus you’ll see a sprinkling of proprietary and other form factor motherboards out there as well. Each form factor has several varieties. The form factor defines the motherboard’s shape size, its orientation, the location of built-in sockets and expansion slots, and so on. The motherboard’s form factor determines the type of power supply and case a PC can use. Form factors are not interchangeable, means which cannot be changed . That means that ATX motherboards fit into ATX cases, and BTX motherboards fit into BTX cases AT motherboard fit into the At case.

3) Motherboard Internal and External Connector

Motherboards today come with connectors to support literally dozens of devices, from the core components of CPU and memory, to sophisticated high-speed networking. You’ve already seen the most common integrated I/O ports , which covered serial, parallel, keyboard, mouse, video, audio, multimedia, MIDI/joystick, modem,b network, USB, FireWire, and SCSI ports.  CPU, RAM, hard drives, removable drives, and expansion slots. When you upgrade or recommend an upgrade, you must address one question: Can the hardware do the job desired by your client? If your client wants to play the latest and greatest games, for example, you need to look at his or her machine and determine its capability.RAM slots to install 2+ GB of memory? Does the chip set support that much? Look at the expansion slot for the
video card. Is it AGP or PCI Express? Does it have the number and type of expansion slots needed for future growth? If your client wants to get a new, high-speed scanner—a more mundane example— you need to weigh several factors. If the motherboard has a FireWire port, just recommend a FireWire-capable scanner and the client is set. Ifn the motherboard has USB but not FireWire, on the other hand, you need to determine whether the USB is Hi-Speedn or plain vanilla USB. If the latter, buying a Hi-Speed USB–capable scanner and plugging it into the lower speed connection would work, but would the client be getting his money’s worth? Of course not! So a good recommendation to overcome this motherboard limitation would be to go for the Hi-Speed scanner and install a Hi- Speed USB controller into an expansion slot. By examining the capabilities and limitations of specific motherboards, you can provide the right experience for your clients.