Networking Flashcards
What is WAN?
Wide area network
What are the advantages of networking?
Communication - transferring files across a network
Sharing resources - files on one computer can be accessed by others and multiple computers can share a printer etc
Networking management - can log onto any computer within a LAN will give you your personal files
What is a router?
This allows communication between at LAN and the Internet
What is a hub?
A device which can have lots of computers connected to it usually with Ethernet cables and allows computers to communicate with one and other
What is a switch?
Performs the same job as a hub (connecting computers so they can communicate) but it remembers the locations of the devices plugged into it making it more efficient because fewer unnecessary signals travel down the wrong cable
What is a wireless access point?
Any device which allows connection to the network without any cables (usually a router)
What is a network interface card?
Each computer connected to an network must have one of these, this replaces where the Ethernet cable would be attached / where the wireless signal would be recieved
What are the common models for creating a network?
Client server
Peer-to-peer
What is a client-server model?
A server holds all of the files, if any of the clients want a file they they must request the files from the server
What is a peer-to-peer model?
This model is where all computers have equal standing they all store files and any peer can transmit a file to another file
What model is the most secure?
Client-server because security can be focused on the machine which holds all of the files
What is an IP (Internet protocol) address?
A unique number assigned to a device on a network. It ensures data reaches the right device
Not all devices have the same IP address everyone time they log onto the network
What is a MAC (media access control) address?
Another unique number hard wired into a device which cannot be changed
It is a hexadecimal number
What is a protocol?
These are used in communication between computers and their peripherals (eg printers, scanners) and between computers on a network.
A protocol is a set of rules that computers must follow in order to communicate
What is HTTP?
Hypertext transfer protocol
This is a set of rules governing how hypertext is moved around the Internet from device to device
What is POP3?
Post office protocol version 3
A protocol for accessing emails, it is commonly used in Microsoft outlook
It takes the emails from an online location and open them in the outlook environment
What is a SMTP?
Simple mail transfer protocol
Where POP3 is used to retrieve emails, SMTP is used to send them from one server to another
What is FTP?
File transfer protocol
How files are moved from one computer to another across the Internet
Heavily relied on in building websites so the developer can move their files from their computer to a server which they can then be accessed publicly
What is LAN?
Local area network
What is a packet?
When data is sent across a LAN or a WAN it is broken up into small chunks, packets.
What is inside a packet?
Packet header - includes the source address and destination of the packet as well as an identification number which is needed to reassemble the data
What are the advantages of packaging?
The packers don’t need to take the same routes around the network as each other
The packets don’t need to arrive in the same order as they left as they get reassembled
If one packet is sent incorrectly only that packet needs to be resent not the entire piece of data
What are methods of network security?
Passwords
User access levels
Encryption
What are some network policies?
Acceptable use
Backup
Failover
Disaster recovery
Archive
What is acceptable use?
The policy states what certain users are permitted to do and what their not permitted to do
What is the backup policy?
States what data will be backed up from the network, how / where it will be backed up and how it will be used to store data
TCP/IP
De facto standard for transmitting data online
What is TCP concerned with?
The hosts connection
What is IP concerned with?
Packet construction
How are packets transported around a network and what is this called?
Packet switching is: Forwarding from one router to another
How does packet switching improve reliability of sending messages?
If one route is down another can be found
TCP/IP
Transmission Control Protocol / Internet Protocol
TCP
Concerned with the connection of hosts
IP
Concerned with the construction of packets
What is a protocol ?
Rules and standards
What are packets?
Pieces of a message
What is packet switching?
Where packets from the same message take different routes to avoid traffic
What is IP addressing?
The addresses which packets are sent to
What bit numbers are IP addresses?
32 bits
What is a MAC address?
A unique number stored in NIC cards so the device can be identified on a network
What type of number are MAC addresses?
Six pairs of hexadecimal
Backups
A backup of all of the data stored in a network, should be done regularly to keep it up to date
Archives
Old data no longer in regular use kept for legal reasons and in case it is needed again
Failover
Software which detects potential disasters and if so transfers data to a duplicate system to avoid data loss
Disaster recovery
A documented plan which covers what to do in the event of data loss
