1.3.2 - Wired/Wireless, Protocols & Layers Flashcards
What is an Ethernet?
- A Wired Network
- Used for communicating on a LAN
- A standard for network technologies
- A family of protocols for networking local area networks
What are the advantages / disadvantages of the Ethernet?
A:
- Includes protocols & provides reliable, fast communication between two points
D:
- User location is limited by the need for a physical cable connection
- Ethernet relies on lots of cables, connections, ports etc. which affects costs
What are Wifi & Bluetooth?
- Wireless networks
Wifi: - Wifi has a larger range than bluetooth (100m > 10m)
- A suite of protocols allowing devices to connect to a wireless network
Bluetooth: - A method of exchanging data wirelessly over short distances, (much shorter than Wi-Fi)
- Protocol for the transmission of data using short-wavelength UHF radio waves
What are the advantages of WiFi?
- Users can move around freely
- Easier & less expensive to set up
- Convenient
- Can handle large number of users
- Transferring info is much easier
What are the disadvantages of WiFi?
- Slower speed than wired networks
- Relies on signal strength
- Signal can be obstructed
- Less secure
What are the advantages / disadvantages of Bluetooth?
- Ideal for connecting personal devices
- Short range (10m)
- Low power consumption compared to WiFi
What is a Wired Connection?
Media for physically connecting network end points
What is a Wireless Connection?
Any connection made between two or more devices which does not involve the need for a physical connection
What is Encryption?
Encoding readable data called plaintext into unreadable data called ciphertext using a key
Why is Encryption important?
- Wireless Networks broadcast data, so it needs to be encrypted to be secure
How does Encryption work?
- Data is scrambles into cipher text using a master key created from the SSID and password
- Decrypted by receiver using the same master key, so key is not transmitted
What is an IP Address?
Used to route packets on a WAN
A unique string of numbers separated by full stops that identify each computer using the Internet Protocol to communicate over a network
What are the formats of an IP Address?
IPv4:
- 32 bits, 4 numbers in range 0-255
eg. 128.69.1.0
IPv6:
- 128 bits, eight groups of hex values
eg. 2001:0db8:85a3:0000:0000:9a2e:0370:7334
What is a MAC Address?
- Assigned to devices & used to route frames on a LAN
- Unique to every network interface card
- A unique identifier assigned to a network interface card for communications at the data link layer of a local network
What are Standards?
A set of specifications for hardware & software
Why are standards useful?
- It allows manufacturers & producers to create products and services that are compatible
- Most devices wouldn’t be able to successfully communicate/interact without standards
What is a Protocol?
A set of rules that allows two devices to communicate
TCP/IP
Transmission Control Protocol/Internet Protocol
- TCP Provides error free transmission between two routers
- IP Routes packets across a WAN
- Both make the TCP/IP protocol stack
HTTP
Hyper Text Transfer Protocol
- A client-server method of requesting & delivering HTML web pages
HTTPS
Hyper Text Transfer Protocol Secure
- Encryption and authentication for requesting & delivering HTML web pages
- Used when secure info needs to be transferred, like bank details
FTP
File Transfer Protocol
- Sends files between computers, usually on a WAN
POP
Post Office Protocol
- Retrieves emails from a mail server, removes it & transfers to your device
SMTP
Simple Mail Transfer Protocol
- Sends emails to an email server
IMAP
Internet Message Access Protocol
- Used by mail clients to manage remote mail boxes & retrieve emails from a mail server
What is Layering?
Divide a complex task of networking into smaller, simpler tasks that work with each other
What are the advantages of Layering?
- Reduces complexity of the problem into manageable sub-programs
- Devices can be manufactured to operate at a particular layer
- Products from different vendors will work together
How layers are used in protocols
Layer
4 : Browser using HTTPS
3 : TCP Error Handling
2 : IP Routing
1 : MAC Frames sent over