LAN (Local Area Network)
a geographic network that covers a relatively small geographic area such as a building or a office space - no more than a mile distance between computers
WAN (Wide Area Network)
A network that spans a long distance and connects two or more LANs.
Analog Signal
continuous electrical signals or waves sent by a computer to display information on a monitor
Digital signal
A system of discrete states: high or low, on or off, 1 or 0 sent by a computer to display information on a monitor
twisted-pair cable
Cables made of copper wires that are twisted around each other and are surrounded by a plastic jacket (such as traditional home phone wire).
fiber-optic cable
A cable that transmits data at close to the speed of light along glass or plastic fibers. This type of wiring is expensive, but is immune to light, sound, and electrical interference.
client-server LAN
A computer (or more than one computer) called a server manages the network resources for all of the client devices on the network
peer-to-peer LAN
There is no server, and people on the network each determine what files they will share with others on the network.
Physical media
the cabling and connectors used to interconnect the network devices.
wireless communication
Communications media that do not use cables but instead rely on radio waves to communicate.
Intranets
a type of WAN in which private company networks allow employees to easily access, share, and publish information using internet software
Extranets
a type of WAN in which private intranets extended to authorized users outside the organization
modem
A device converts analog signals to digital signals, typically seen in areas that use telephone lines
Router
A device that transfers data from one network to another in an intelligent way
Network Interface Cards
Provides a place to plug the network cable into the computer and it creates and sends the signal from one network component to another.
Coaxial cable (coax)
Cable consisting of a hollow outer cylindrical conductor that surrounds a single inner wire conductors
wired communication
Use of wires and cables to connect and communicate for internet access
Client Device/Host/Node
A device (Tablet, Phone, Desktop, Laptop) that is connected to the network
Servers
Computers or devices that provide access to various network services, such as printing, data storage, and communications.
Internet Service Provider (ISP)
a company that provides access to the internet for a monthly fee
Copper Cable
Low cost method of providing connections in a network. Signal strength is lost with distance and can only work over short distances. Suffers from electrical interference.
cellular network
A wireless network which uses cell towers to transfer information.
Satellite Network
A Wireless network which uses satellites to communicate and transfer information
TCP/IP Model Layers
1. Application
2. Transport
3. Internet
4. Network Access
Application Layer
The first layer of the TCP/IP model. Application layer protocols enable software programs to negotiate formatting, procedural, security, synchronization, and other requirements with the network.
Transport Layer
Second layer in the TCP/IP stack. Sets-up a connection between the two hosts, agrees the protocol and packet size. These two Protocols are TCP and UDP
Internet Layer
responsible for addressing, packaging, and routing messages on the Internet
Data Link/Network Access Layer
handles all the physical details of interfacing with the cable, including the network interface card and a device drivers.
TCP (Transmission Control Protocol)
Provides reliable in the Transport-layer protocol, ordered, and error-checked delivery of a stream of packets on the internet. TCP is tightly linked with IP and usually seen as TCP/IP in writing.
UDP (User Datagram Protocol)
A Transport-layer protocol that is one of the protocols in the Internet protocol suite, and excludes error checking and quality assurance, this protocol is faster than TCP.
ARP
Address Resolution Protocol. Resolves IP addresses to MAC addresses. ARP Tables include a map of the different devices with a MAC address
Internet Protocol (IP)
The network protocol that deals with the routing of packets through interconnected networks to the final destination. Every hosts on a network is given an IP Address to identify it on the network.
Packet Structure
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IP address
A number assigned to any node that is connected to the Internet. They are formatted to take 4 different spaces Ex:
192.168.12.2
IPv4
The Internet Protocol version 4 is the dominant protocol for routing traffic on the Internet, specifying "to" and "from" addresses using a 32-bit binary set
IPv6
A new protocol developed to replace IPv4, addressing the issue of IP address exhaustion using a 128-bit binary set
MAC address (Media Access Control)
A unique identifier similar to a serial number assigned to equipment or devices at the time of manufacture. On a network, an IP address is linked to a MAC address
Subnetting
The process of logically dividing a network
into smaller subnetworks or subnets.
Network ID
The portion of an IP address common to all nodes on the same network or subnet.
Network ID: 172.30.0.0
Host 1's Address: 172.30.15.12
Host 2's Address: 172.30.15.24
DNS (Domain Name System)
The Internet's system for converting alphabetic names into numeric IP addresses.
FQDN (Fully Qualified Domain Name)
A host name plus domain name that uniquely identifies a computer or location on a network.
URL (Uniform Resource Locator)
A location or address identifying where documents can be found on the Internet; a Web address or a 'link'
default gateway
The first IP address of the device that a client computer will look for when attempting to gain access outside the local network. This is usually the IP of the Router on the network
DHCP (Dynamic Host Configuration Protocol)
A network protocol that provides automatic
assignment of IP addresses and other TCP /IP configuration information to devices on the network.
top-level domain
Domains (including .net, .org, .com, .mil. and the set .xx country codes) at the end of a domain name are the highest level of the domain name hierarchy.
Hyper Text Transfer Protocol (HTTP)
The way data is transferred to an external site through a server.
HTTPS (Hypertext Transfer Protocol Secure)
An encrypted version of HTTP. It ensures information you access is securely accessed
FTP (File Transfer Protocol)
A protocol used to move files and folders over a network or the Internet.
SOHO (Small office/home office)
A small business office with between 1 and 10 users.
Wireless Access Point (WAP)
is a network device that serves as an interface between devices and the network. Access Points are used to extend wireless access in a network in the event the Router is further away.
DSL (digital subscriber line)
A telephone line that carries digital data from end to end, and is used as a type of broadband Internet access. These usually require a Modem to convert phone signals to digital signals
Fiber Optic Network
Dedicated wire to rapidly and reliably transmit masses of multimedia data at the same time that it's handling voice messages.
Fiber to the Home (FTTH)
provides home users with Internet access via fiber-optic cable
Fiber to the Curb (FTTC)
Takes the fiber even closer to the subscriber, bringing the optical fiber directly to the "curb" near customer homes and/or businesses.
ipconfig
Windows command that shows the IP configuration settings on a PC
Wireless Standards
802.11b - 2.4 GHz 11 Mbps
802.11a - 5 GHz, 54 Mbps
802.11g - 2.4 GHz, 54 Mbps
802.11n - 5 GHz, 108 Mpbs
802.11ac - 5 GHz, 1.7 Gpbs
2.4 GHz
Wireless networking radio frequency that has moderate speeds but offers longer ranges.
5 GHz
Wireless networking radio frequency that has faster speeds but offers shorter range
Line of Sight (LOS)
The area you can clearly see in any direction
Data Encryption
A security measure for wireless networks that scrambles data transmitted between network devices.
WEP (Wired Equivalent Privacy)
A key encryption technique for wireless networks that uses keys both to encrypt data
WPA
Wireless Protected Access. Wireless network encryption system.
WPA2
Wireless Protected Access 2. Wireless network encryption system. This is considered the most secure encryption standard for wireless networks
Wireless Enterprise Network
Same WiFi standards, but using enterprise-level equipment.
Malware
software that is intended to damage or disable computers and computer systems.
Viruses and Worms
The two types of malware that have the primary objective of infecting a computer.
Trojan Horse
a program that appears desirable but actually contains something harmful
Adware
computer software that displays advertisements that can be a nuisance to the end-user.
Spyware
A type of Malware that locates and saves data from users without them knowing about it.
digital certificate
a notice that guarantees a user or a website is legitimate
Cookies
small computer programs left behind on your computer when you visit a website. To target specific ads to you.
Personally Identifiable Information (PII)
any data that can be used to identify, locate, or contact an individual. Ex:
Name
Address
Date of Birth
pop-up ad
A small web page containing an advertisement that pops on the users screen
Firewall
Part of a computer system that is designed to block unauthorized access of applications and ports.
antivirus software
Software used to detect and eliminate computer viruses and other types of malware.
Private browsing
A feature of all modern browsers that will delete your history, cache, and cookies the moment you close the private window.
network appliance
A device or equipment dedicated to working with a network: Ex:
-Switches
-Routers
-Wireless Access Port
Network Attached Storage (NAS) or File Servers
A device or devices that have many hard drives to provide large amounts of disk space.
Attenuation
Loss of power in a signal as it travels long distances
Backup
A copy of data that is made in case the original data is lost or damaged. The backup can be used to restore the original data.
Printer Sharing or Print Server
allows a computer user to share his or her attached printer with other users on a network
cloud storage
An Internet service that provides remote storage or access to resources to users through an app or website. The term 'Cloud' is used in terms of high availability, much like actual clouds.
Universal Naming Convention (UNC)
A naming system used by Windows computers to locate network file shares and network printers. The format is \\computername\foldername.
Drive Mapping
A process of assigning a drive letter to a storage device located on a different network workstation.
SMTP
(Simple Mail Transfer Protocol) The main protocol used to send electronic mail from server to server on the Internet.
IMAP (Internet Message Access Protocol)
a common protocol for retrieving email messages from the server, but is not directly downloaded
POP(Post Office Protocol)
used to retrieve email from a server and download it directly on the device.
proxy server
A form of network security that acts as a go-between for who can make requests or access resources on a network.