Course 3 Connect and Protect: Networks and Network Security

Data packet

A basic unit of information that travels from one device to another within a network

Stateful

A class of firewall that keeps track of information passing through it and proactively filters out threats

Stateless

A class of firewall that operates based on predefined rules and does not keep track of information from data packets

Botnet

A collection of computers infected by malware that are under the control of a single threat actor, known as the

Cloud network

A collection of servers or computers that stores resources and data in remote data centers that can be accessed via the internet

User Datagram Protocol (UDP)

A connectionless protocol that does not establish a connection between devices before transmissions

Modem

A device that connects your router to the internet and brings internet access to the LAN

Switch

A device that makes connections between specific devices on a network by sending and receiving data between them

Baseline configuration (baseline image)

A documented set of specifications within a system that is used as a basis for future builds, releases, and updates

World-writable file

A file that can be altered by anyone in the world

Port filtering

A firewall function that blocks or allows certain port numbers to limit unwanted communication

TCP/IP model

A framework used to visualize how data is organized and transmitted across a network

Network

A group of connected devices

Replay attack

A network attack performed when a malicious actor intercepts a data packet in transit and delays it or repeats it at another time

IP spoofing

A network attack performed when an attacker changes the source IP of a data packet to impersonate an authorized system and gain access to a network

Smurf attack

A network attack performed when an attacker sniffs an authorized user's IP address and floods it with

Hub

A network device that broadcasts information to every device on the network

Router

A network device that connects multiple networks together

Hypertext Transfer Protocol Secure (HTTPS)

A network protocol that provides a secure method of communication between clients and servers

Simple Network Management Protocol (SNMP)

A network protocol used for monitoring and managing devices on a network

Address Resolution Protocol (ARP)

A network protocol used to determine the MAC address of the next router or device on the path

Firewall

A network security device that monitors traffic to or from your network

Virtual private network (VPN)

A network security service that changes your public IP address and masks your virtual location so that you can keep your data private when you are using a public network like the internet

Wide Area Network (WAN)

A network that spans a large geographic area like a city, state, or country

Local Area Network (LAN)

A network that spans small areas like an office building, a school, or a home

Domain Name System (DNS)

A networking protocol that translates internet domain names into IP addresses

Encapsulation

A process performed by a VPN service that protects your data by wrapping sensitive data in other data packets

Secure File Transfer Protocol (STP)

A secure protocol used to transfer files from one device to another over a network

Multi-factor authentication (MFA)

A security measure which requires a user to verify their identity in two or more ways to access a system or network

Secure shell (SSH)

A security protocol used to create a shell with a remote system

Network segmentation

A security technique that divides the network into segments

Security zone

A segment of a company's network that protects the internal network from the internet

Proxy server

A server that fulfills the requests of its clients by forwarding them to other servers

Forward proxy server

A server that regulates and restricts a person's access to the internet

Reverse proxy server

A server that regulates and restricts the internet's access to an internal server

Network protocols

A set of rules used by two or more devices on a network to describe the order of delivery of data and the structure of data

IEEE 802.11 (Wi-Fi)

A set of standards that define communication for wireless LANs

Internet Protocol (IP)

A set of standards used for routing and addressing data packets as they travel between devices on a network

Penetration testing (pen test)

A simulated attack that helps identify vulnerabilities in systems, networks, websites, applications, and processes

Patch update

A software and operating system update that addresses security vulnerabilities within a program or product

Port

A software-based location that organizes the sending and receiving of data between devices on a network

Open systems interconnection (OSI) model

A standardized concept that describes the seven lavers computers use to communicate and send data over the network

Controlled zone

A subnet that protects the internal network from the uncontrolled zone

Ping of death

A type of DoS attack caused when a hacker pings a system by sending it an oversized IMP packet that is bigger than 64KB

Internet Control Message Protocol (IMP) flood

A type of DoS attack performed by an attacker repeatedly sending

Synchronize (SYN) flood attack

A type of DoS attack that simulates a TCP/IP connection and floods a server with packets

Passive packet sniffing

A type of attack where a malicious actor connects to a network hub and looks at all traffic on the network

Active packet sniffing

A type of attack where data packets are manipulated in transit

Distributed denial of service (DDoS) attack

A type of denial of service attack that uses multiple devices or servers located in different locations to flood the target network with unwanted traffic

Media Access Control (MAC) address

A unique alphanumeric identifier that is assigned to each physical device on a network

Internet Protocol (IP) address

A unique string of characters that identifies the location of a device on the internet

Wi-Fi Protected Access (WPA)

A wireless security protocol for devices to connect to the internet

Hypertext Transfer Protocol (HTTP)

An application layer protocol that provides a method of communication between clients and website servers

Security information and event management (SIEM)

An application that collects and analyzes log data to monitor critical activities for an organization

Denial of service (DoS) attack

An attack that targets a network or server and floods it with network traffic

On-path attack

An attack where a malicious actor places themselves in the middle of an authorized connection and intercepts or alters the data in transit

Transmission Control Protocol (TCP)

An internet communication protocol that allows two devices to form a connection and stream data

Internet Control Message Protocol (IMP)

An internet protocol used by devices to tell each other about data transmission errors across the network

Cloud-based firewalls

Software firewalls that are hosted by the cloud service provider

Operating system (OS)

The interface between computer hardware and the user

Bandwidth

The maximum data transmission capacity over a network, measured by bits per second

Hardware

The physical components of a computer

Uncontrolled zone

The portion of the network outside the organization

Packet sniffing

The practice of capturing and inspecting data packets across a network

Cloud computing

The practice of using remote servers, application, and network services that are hosted on the internet instead of on local physical devices

Network log analysis

The process of examining network logs to identify events of interest

Security hardening

The process of strengthening a system to reduce its vulnerabilities and attack surface

Speed

The rate at which a device sends and receives data, measured by bits per second

Subnetting

The subdivision of a network into logical groups called subnets