IT2203 Network Fundamentals and Protocols

Flashcards covering key networking concepts, protocols, and technologies discussed in the lecture notes.

Internet

The largest computer network in the world, evolved from ARPAnet in 1969.

Network Communication

Communication between terminal devices through a computer network.

Waves

Disturbances that cause energy to travel through a medium.

Wavelength

Horizontal distance of a wave from a point to the corresponding point on the next wave, measured in meters.

Amplitude

Vertical distance from a point on the wave from the horizontal axis, measured in volts, amperes, or watts.

Phase

Position of the waveform relative to time zero; measurement of the delay of the wave relative to some fixed reference point.

Frequency

Number of waves made per second or cycles per second, measured in Hertz (Hz).

Period

Amount of time required to complete one full wave cycle, expressed in seconds.

Analog Wave

A wave in which both amplitude and time continuously vary over their respective intervals.

Signal

A sign or indication that conveys information.

Digital Wave

A wave with discrete states, such as high or low, on or off.

Wired or Bounded Media

Networking media that use cables and are limited by physical geography.

Wireless or Unbounded Media

Networking media that do not use cables and are not bounded by physical geography.

Simplex Mode

Connection where data flows in one direction only (unidirectional).

Half-duplex Mode

Connection where data can flow in both directions, but not simultaneously.

Full-duplex Mode

Connection where data simultaneously flows in both directions.

Serial Transmission

Transmission in which data bits line up in a series and are sent over a single wire at a time.

Parallel Transmission

Transmission where a group of bits is sent simultaneously, each using a different channel.

Serial Cable

A standard for serial data communications intended to operate over distances of up to 50 feet with speeds less than 20Kbps.

Coaxial Cable

Cable with two conductors enclosed by an insulating protective coating.

Thin (Thinnet) Cable

A flexible coaxial cable about 0.25 inches thick, using BNC-T connectors.

Thick (Thicknet) Cable

A relatively rigid coaxial cable about 0.5 inches in diameter, using vampire tap connectors.

Twisted Pair Cable

Cable consisting of two insulated strands of copper wire arranged in a regular spiral pattern.

Unshielded Twisted-Pair (UTP) Cable

Twisted pair cable that contains no shielding.

Attenuation

Signal loss due to impedance.

Crosstalk

Effect where twisted-wire pairs produce a magnetic field cancellation, limiting signal degradation.

Shielded Twisted-Pair (STP) Cable

Twisted pair cable that combines twisting wires, cancellation, and shielding techniques.

Fiber Optic Cable

Cable consisting of extremely thin glass fibers that conduct modulated light transmissions.

Core

Innermost section of a fiber optic cable consisting of thin strands of glass or plastic.

Cladding

Outer optical glass or plastic coating that surrounds and traps light in the core.

Coating

Plastic material which helps to shield the core and cladding from damage.

Strengthening Fibers

Protection for the core against compressive forces or crushing and tension or excessive pulling.

Cable Jacket (Sheath)

Outermost layer of a fiber optic cable that protects against moisture, abrasion, crushing, and other environmental dangers.

Single-mode Fiber Optic Cable

Fiber optic cable type that allows light waves to travel along a single path; used for high-speed transmission over long distances.

Multimode Fiber Optic Cable

Fiber optic cable type that allows light waves to travel into numerous paths at various angles; often used in local area networks.

Radio Wave

Wireless medium used for multicast communications and paging systems over long distances.

Antenna

Metallic structure that acts as a transducer, converting electrical energy to electromagnetic energy.

Line of Sight Propagation

Method by which radio waves travel directly from the transmitting antenna to the receiving antenna.

Ground Wave Propagation

Method by which radio waves are radiated directly towards the earth’s surface.

SkyWave Propagation

Method by which radio waves radiate upwards from the transmitting antenna towards the ionosphere.

Space Wave Propagation

Method by which radio wave radiation exceeds 30 MHz up to 300 GHz.

Infrared (IR)

Wireless medium used for short-range communication in a closed area using line-of-sight propagation.

Microwave

Wireless medium used for unicast communication such as Bluetooth, WiMAX, cellular networks, and Wi-Fi.

Bluetooth

Short-range wireless communication technology that allows devices to transmit data or voice wirelessly over a short distance.

Network Topology

Schematic description of a network arrangement, connecting various nodes through lines of connection.

Star Topology

Topology where computers are connected to a single hub.

Bus Topology

Topology where every computer and network device is connected to a single cable.

Ring Topology

Topology that forms a ring where each computer is connected to two neighbors.

Tree Topology

Topology that has a root node and all other nodes are connected to it forming a hierarchy.

Mesh Topology

Topology with a point-to-point connection to other nodes or devices.

Partial Mesh Topology

Topology where some systems are connected in a mesh fashion, but some devices are only connected to two or three devices.

Full Mesh Topology

Topology where each node or device is connected to every other node or device.

Hybrid Topology

Topology that consists of a mix of two different types of topologies merging as one network.

Terminal Device

End-device of the data communication system, includes DTE such as PC, phone, printers, and servers.

Switch

Device closest to end-users, used to access the network and switch data frames.

Broadcast Domain

Set of nodes that can receive broadcast packets from a node.

Router

Network-layer device that forwards data packets on the Internet.

Modem

Device that connects a network to the Internet and translates signals.

Gateway

Term for a router that provides protocol conversion, route selection, and data exchange between networks with different architectures.

Firewall

Network security device used to ensure secure communication between two networks.

Wireless Devices

Network that uses radio waves, laser, and infrared signals to replace some or all transmission media in a wired LAN.

Wi-Fi

WLAN technology based on the IEEE 802.11 family of standards.

Fat Access Point (Fat AP)

Access Point that works independently and needs to be configured separately, typically used in homes.

Fit Access Point (Fit AP)

Access Point that needs to work with the AC and is managed and configured by the AC, typically used in enterprises.

Access Controller (AC)

Device generally deployed at the aggregation layer of the entire network, providing wireless data control services.

Local Area Network (LAN)

Network generally covering an area of a few square kilometers, connecting terminals that are close to each other.

Metropolitan Area Network (MAN)

Large-sized LAN, requiring high costs but providing a higher transmission rate, covering a university campus or city.

Wide Area Network (WAN)

Network generally covering an area of several kilometers or larger, connecting LANs or MANs that are far from each other.

OSI Reference Model

Descriptive network scheme that describes how information or data makes its way from application programs through a network medium.

OSI - Application Layer

OSI layer closest to the user, providing network services to the user’s applications.

OSI - Presentation Layer

OSI Layer that ensures that the information is readable by the application layer of another system.

OSI - Session Layer

OSI Layer that defines how to start, control and end conversations between applications.

OSI - Transport Layer

OSI Layer that regulates information flow to ensure end-to-end connectivity between host applications.

OSI - Network Layer

OSI Layer that defines end-to-end delivery of packets and how routing works.

OSI - Data Link Layer

OSI Layer that provides access to the networking media and physical transmission.

OSI - Physical Layer

OSI Layer that deals with the physical characteristics of the transmission medium.

TCP/IP Model

Networking model with a set of communication protocols for the Internet.

TCP/IP - Application Layer

TCP/IP Layer that represents an interface through protocols that enable services to be applied to end-user application processes.

TCP/IP - Transport Layer

TCP/IP Layer responsible for reliable end-to-end data delivery from the source host to the destination host.

TCP/IP - Internet Layer

TCP/IP Layer responsible for the delivery of service requests that respond from the transport layer and arrive at their destination.

TCP/IP - Network Access Layer

TCP/IP Layer concerned with issues that an IP packet requires to make a physical link to the network media.

Standards

Documented agreements containing technical specifications that stipulate how a product or service should be designed or performed.

IEEE (Institute of Electrical and Electronics Engineers)

International society composed of engineering professionals, known for standardizing LAN technologies.

ANSI (American National Standards Institute)

Organization composed of representatives from industry and government, determining standards for electronics and industry.

EIA (Electronic Industries Alliance)

Trade organization composed of representatives from electronics manufacturing firms across the United States.

TIA (Telecommunications Industry Association)

Organization that focuses on standards for information technology, wireless, satellite, fiber optics, and telephone equipment.

IETF (Internet Engineering Task Force)

Organization responsible for the overall development of the Internet and the standardization of internetworking technologies.

ISO (Organization for Standardization)

International standards organization responsible for a wide range of standards, including many relevant to networking.

SMTP (Simple Mail Transfer Protocol)

TCP/IP protocol for reliable and efficient transfer of electronic mail service on the Internet.

POP3 (Post Office Protocol, version 3)

TCP/IP protocol designed to allow a workstation to retrieve mail that the server is holding for it.

TFTP (Trivial File Transfer Protocol)

Small and simple alternative to FTP that uses UDP to transfer files between systems.

FTP (File Transfer Protocol)

TCP/IP protocol that enables the sharing of computer programs and data between hosts, using TCP connections.

NFS (Network File System)

TCP/IP protocol that enables computers to mount drives on remote hosts and operate them as local drives.

DNS (Domain Name System)

TCP/IP protocol used on the Internet for translating names of domains into IP addresses.

SNMP (Simple Network Management Protocol)

TCP/IP protocol that monitors and controls the exchange of management information in networks.

Telnet

TCP/IP protocol that uses TCP to establish a connection between server and client, creating a Virtual Terminal (VTY) session.

rlogin (Remote login application)

UNIX command that allows authorized users to log in to other UNIX machines on a network.

HTTP (Hypertext Transfer Protocol)

Application-level protocol service and Internet standard that supports the exchange of information on the World Wide Web.

HTTPS (Hypertext Transfer Protocol over Secure Socket Layer)

Secure message-oriented communications protocol designed for use with HTTP.

SSL (Secure Sockets Layer)

Security protocol that works at a socket level, encrypting/decoding data and authenticating entities.