HOSA Biomedical Equipment Technician - System and Networking

Network

Means two or more connected computers that can share resources like data and applications, office machines, or a combination of these.

Computer Hardware

Parts of a Computer

Central Processing Unit (CPU)

The computer's brain and is the electronic machinery that gives instructions from programs that lets a computer or other device to perform its tasks.

Motherboard

Backbone of the computer - ties the computer's components together at one spot and lets it communicate with each other.

Random-Access Memory (RAM)

Form of computer memory that can be read and changed in any order.

Read-Only Memory (ROM)

Receives data and permanently writes it on a chip. Lasts even after you turn off your computer. The data is coded not to be overwritten.

Hard Drive

Where your permanent computer data is stored. Whether you save a file, photo, or software to your computer, its stored in your hard drive.

Peripheral device

Auxiliary device that puts information into and gets information out of a computer.

Functions of a RAM

Handles your temporary memory (the data you're using). The more RAM, the better your computer does in terms of communication.

Two types of RAM

SRAM - static, does not need to be refreshed, uses less power, memory can be accessed quickly; DRAM - dynamic, needs to be refreshed often, cheaper, offers greater memory capacity.

Operating System (OS)

File management layer translates logical file requests from command shell into physical I/O request.

Application Software

Acts as an interface for application programs, software that enables the functions and use of a device.

Coaxial

Contains a center conductor made of copper surrounded by a plastic jacket with a braided shield.

Twisted Pair

Contains many individually insulated wires that are twisted together in pairs.

Unshielded Twisted-Pair

Most common cable type because of its cost, its level of difficulty (easy) and lets transmission rates that were impossible 10 years ago.

Fiber Optic

Transmits digital signals using light impulses rather than electricity, that means its immune to EMI and RFI.

Ring Topology

All devices are connected to each in a virtual ring. It does not have to be terminated.

Star Topology

Most popular typology, each device has a dedicated connection to the hub or switch.

Bus Topology

Signals from each device travel on a bidirectional bus. Uses CSMA/CD software to sense when a line is busy.

Mesh Topology

Every computer has a dedicated connection to every other computer on the network.

Hybrid Networks

Designed to take advantage of the strengths of every combined network.

Carrier Sense Multiple Access/Collision Detection

Software that senses when the line is busy to avoid collisions and loss of data.

Personal Area Network (PAN)

Network that is used for communicating among computers and computer devices nearby around a few meters within a room.

Local Area Network (LAN)

Network that is used for communicating among computer devices, usually in an office building or home.

Metropolitan Area Network (MAN)

Network that interconnects users with computer resources in a geographic area or region larger than the area covered by LAN.

Wide Area Network (WAN)

Geographically distributed network composed of LANs joined into a single large network using services given by common carriers.

Wireless Networking

A wireless network is a network that uses wireless data connections between network nodes.

Network Devices

Devices that connect computers and other devices to the internet.

Internet Protocol Stack

The 5-layer model associated with networks is usually known as the TCP/IP model.

Bit

One digit, either a 1 or a 0.

Byte

7 or 8 bits, depending on whether parity is used.

Octet

Made up of 8 bits, is an ordinary 8-bit binary number.

Network Address

The designation used in routing to send packets to a remote network.

Broadcast Address

Used by applications and hosts to send information to all hosts on a network.

Subnet Mask

Applied to an IP address to define which portion of the address is network specific and which is host specific.