Computer Network Connections/Protocols Flashcards
What is a network
A group or system of interconnected people or things
What is a protocol
An agreement or a set of rules for a computer network
What is a computer
An electronic device for storing and processing data in binary form
What are two types of networks that we use
LAN
WAN
What is a WAN network
Wide Area Network. A network when computers have communication using resources, provided by a third party carrier
How does a WAN need to perform
They would acquire cables, telephone lines, satellites and radio waves
What is the largest WAN in the world
The Internet
What are the advantages of WAN
They cover large geographical areas
Increased privacy
Allows users to share resources and application software
Assists global markets and businesses
IT infrastructure is centralized
Benefits the global market and business
What are the disadvantages of WAN
Spans more congestion
More slower
Poor connectivity
Poor maintenance
Problem with resolving
Instalment fees
Huge demands for security options
What is a LAN
Local Area Network. A network that covers a small geographical location on a small site
What are the advantages of LAN
Spans less congestion
More faster than WAN
Works together from different computers via instant messaging
Can access files from any computer
Works collaboratively on the same file
Can share files
What are the disadvantages of LAN
High setup costs
Local area networking added difficulty to security operation
Control on the customer’s part is lost
Security system should be executed if its essential to protect private data
Weak data protection
High maintenance degree
Maximum damage
What is congestion
Clog or block of something
What are two types of mesh LAN networks
Star Topology
Mesh Topology
What is a network topology
The physical and logical arrangement of nodes and connections in a network
What is a mesh/partial mesh network topology
A network setup where each device is interconnected with one another and can rely data easily
What are the benefits of a mesh network topology
Good resilience, np point in failure
Efficient expansion
Efficient modification
No network disruption
If one computer switches off, the system is unaffected, keeps working like normal
No central switch
What are the drawbacks of a mesh network topology
Difficult administration
Difficult maintenance
High installation costs
If one node is added, more nodes will have to keep getting added
Whats the difference between a regular mesh network and a partial mesh network
Partial Mesh Networks have less nodes
They tend to be in conjunction with star mesh networks for bigger communications
What is a node
A device that can send, receive, read data that is connected to a network
What is a star mesh network topology
A network where all computers, devices and nodes are all connected to a central switch
What are the benefits of a star mesh network topology
If one device is turned off, the network is unaffected, keeps continuing like normal
Fast data transfer to hub as each wire isn’t shared with other computers
What are the drawbacks of a star mesh network topology
If the central switch fails, the whole network is turned off
Additional hardware is required such as a central switch and network cables
What is a wireless mesh network
A communication network made up of radio nodes organized in a mesh topology.
What is a data packet
A unit of data that travels along a network path.
More information about a data packet
Each data packet contains the same number of bytes
Packets may flow through Internet via different routes
Each packet is marked with the packet number so that the packets can be put back together by the receiver
Why does packet switching excel circuit switching
Circuit switching involves a dedicated connection setup between two people (you and the caller)
But packet switching solves the problem of there not being enough lines for billions of people sending data across the Internet
Suppose we want to send a 3MB file to someone via the internet. Explain how we can use packet switching to do this.
- Each file is broken up into equal sized data packets of 512 bytes. Each data packet has 512 bytes. Via packets, we can send them via Internet through different routes
- The request is placed in packets
- Each packet gets an address and number each
- Packets are sent around network
- Packets are sent around host server
- The server does a check to see if all the packets are there
- If not
A timeout is sent - If they have arrived
Packets are placed in order - Request is processed
What is a router
A networking device that forwards data packets between computer networks
What are the benefits of packet switching
- More use than circuit switching
- Data packets are easily able to locate the destination without a channel
- Because packet switching allows packets to be resent, amount of lost data packets is reduced
- Each data packet has a fair same amount of bytes
- Packets are always delivered in the correct order
- Calls are done within a steady bandwidth, dedicated channels and a consistent data rate
What are the drawbacks of packet switching
- Only efficient for voice communication
- Resources are used in the right way
- Dedicated channels for circuit switching are unable for other uses
- The more use, the more expensive
Does packet switching require a dedicated channel?
No
What is a DNS server
Domain Network System
What is the function of a DNS server
Turns the web address into an IP address. It holds parts of a database
How many DNS root servers are there
13
What is a database
A structured set of data held in a computer
What happens if a DNS server doesn’t receive a database request
It passes the request to another server until it has the correct name and IP address. The process will keep repeating until done so
What is an IP address
Internet Protocol Address
A unique address that identifies a device on the internet or a local network
Does our IP address change?
Yes it does. If you are in one part of the country, you are assigned a temporary IP address for that part of the country. If we take our device on holiday however, we are given a different IP address as we are in a different part. If we return back to our original place however, our IP address will change back to our original address before holiday
What is an NIC (network interface card)
A circuit board that functions to enable network communications for devices such as computers and network servers. NIC cards work by transmitting signals at the physical layer and deliver data packets at the network layer
What is a MAC address
Media Access Control address
A unique identifier assigned to a network interface controller for use as a network address within communications in a network segment
What is the link between MAC addresses and NIC cards
A MAC address is assigned to each network interface card by the manufacturer
What is the link between MAC addresses and other connections
There may be more than one MAC addresses if there is an Internet or Ethernet connection
What happens when we request a web page
Each router along the way uses the MAC address of the next router. It also is able to send the data packet on the next part of the journey
What are the differences between an IP address and a MAC address
- MAC addresses NEVER change. IP addresses change when changing location.
- IP addresses are 4 bytes
MAC addresses are 6 bytes - IP addresses are expressed in Denary
MAC addresses are expressed in Hexadecimal
IP addresses are configured by software. MAC addresses are configured by hardware
IP addresses are only used for routing across a WAN/internet
MAC addresses are only used within a LAN
What is a switch
A physical component that governs the signal flow. It is the source of connections
What is a hub
A small device that allows wired devices to connect to a network
What is a WAP
Wireless Access Point
A hardware device or configured node on a LAN (Local Area Network)
What are benefits of WAP
- Low costs than conventional infrastructure
- Easier management and maintenance
- More reliability
- Can be scaled up as needs grow
- Broad transmission range
What are drawbacks of WAP
- Slower than dedicated cable networks
- Limited amount of radio channels, can’t support hundreds of simultaneous connections
- Poor stability
- Limited range of operation
- Less secure due to depending on a secret password
What is the job of a router and a switch
A router routes data packets towards correct destination
A switch connects each node in a network
What are similarities of a router and a switch
- Use of device connection
- Data retrieval from devices
- Correct data determination from destination
- Data transmission
What are some differences of a router and a switch
- Switches use MAC addresses
- Routers use IP addresses
- Switches connect nodes and computers
- Routers connect networks and Internet
- Routers store address of attached devices
- Switches record the address attached
- Switches look for correct addresses
What is an Ethernet connection
A family of wired computer networking technologies commonly used in local area networks, metropolitan area networks and wide area networks.
How does an Ethernet connection work
Delivers stable, speedy, secure, wired connections to the internet and between device
What is transmission media
The way that communication is sent through the network
What equipment is used for an Ethernet connection
Twisted copper cables
Fibre optic cables
Coaxial cables
Original copper cables