CCNA Flashcards
Firewall
device that protects networks by montioring traffic and prevents unwanted traffic from accessing network.
ARP (Address Resolution Protocol)
Translates the IP address of a device to a MAC address
Can a device act as a client and server?
Yes and example
client
requests a service from a server. Example
DNS (Domain name system)
A protocol that translates web addresses like www.google.com to IP addresses such as 192.65.52.21. Like a phonebook for computers.
Home IP address
192.168.0.1 or 192.168.1.1
Used to connect to home network(router). This IP address is like a secret code that helps the devices in your house talk to each other and send and receive data.
IP address (Internet Protocol address)
Unique address that identifies a device in a network
Local host
127.0.0.1, this is your computer itself and used for testing programs or trying out new things without anyone else seeing.
Mac Address (Media Access Control address)
AKA physical address, unique address assigned to NIC in a device
Network
A group of connected devices that share resources such as files, pictures, etc.
Network Topology
Diagram of the arrangement of devices in a network
Open Systems Interconnection Model
7 layer model that describes how computer systems communicate over a network. (Physical, Data Link, Network, Transport, Session, Presentation, Application)
Phishing
A fraudulent email that contains malware or to get sensitive data. It may seem legit.
Ransomware
deny a user or organization access to file unless a payment to made to hacker
Router
Router is used to send data over internet and between LANS
Server
provides a client with a service, Example:
Social Engineering
manipulating someone to perform actions or get confidential information
Spoofing attack
attacker pretends to be a person, organization, etc to get confidential information. Example:
Techniques to perform Reconnaissance Atttack
- Gather info about target and find target’s network address(whois, google, organization website, etc)
- Ping sweep-to find active IP addresses
3.Port scan(Nmap, Superscan, etc)
4.Run vulnerability scanner- with identified ports, determine the type and version of OS running on the host(Nipper, SAINT, etc)
5.Run exploitation-discover vulnerable services that can be exploited.
Trojan Horse
is a type of malware that appears legitimate and safe, but is actually malware
Virus
A malicious piece of computer code designed to spread from device to device.
What is Ethernet
Networking technology that is used in a wired LAN or WAN to create connections between devices using protocols.
Static Route
A route that you manually configure in a routing table
Next Hop
The hop data has to go through to make it to the destination
Routing table
shows a list of known destinations and how to get there (show IP route command)
Default gateway
a router that directs traffic where it needs to go
Physical layer
Layer responsible for how data is transmitted and what medium is used to transmit it
TCP/IP
TCP is used with IP to ensure reliable transmission of packets, when computers want to send data to each other via TCP/IP, a connection must be made over the internet
UDP
UDP doesn’t use error checking or 3-way handshake. The packets are just sent to the recipient. This protocol is faster than TCP/IP
What are the two routing methods?(methods routers use to learn routes)
Static Routing - Network Engineer manually configures routes on the router
Dynamic Routing - Routers use dynamic routing protocols such as OSPF to share info with each other automatically and build a routing table.
OSPF (Open shortest path first)
Router protocol used to find the best path for packets as they pass through a set of connected networks
Ping Sweep
is a technique used in computer networking to discover and identify active hosts (computers or devices) on a network. It involves sending a series of network ping requests to a range of IP addresses within a specific network or subnet
Port Scan
scanning tool or software that checks different ports on a computer or device to see if they are open or closed. It sends messages, called network packets, to each port and waits for a response. Based on the response or lack thereof, it determines whether the port is open, closed, or filtered.
vulnerability scanner
software tool used to check if computer systems, networks, or applications have any hidden problems or weaknesses that could make them not work properly.
Broadcast domain
group of devices that will receive broadcast frame by a member in the group
VLAN
A way to logically split up a broadcast domain
