Lecture 2 - Networks Flashcards
What are the 5 types of networks?
- LAN
- WLAN
- PAN
- MAN
- WAN
- VPN
What is a LAN?
Local Area Network
- only in a specified area e.g. a flat
What is a PAN?
Personal Area Network, it is a network of individual’s range. It is connected by bluetooth or directly by a cable
What is a WLAN?
Wireless Local Area Network, it is the same as LAN, but strictly wireless
What is a MAN?
Metropolitan Area Network, a network that is city wide
What is a WAN?
Wide Area Network, it spans many geographical areas. Internet is a WAN.
What is a VPN?
Virtual Private Network, it is when we connect to another network from another. It was created due to security issues.
What does a typical network consist of?
ISPs, broadband users , routers, switches, LANs, web servers etc.
What are the 7 layers of the OSI model?
- Physical
- Data Link
- Network
- Transport
- Session
- Presentation
- Application
What is the OSI model for?
To define how data can be transferred between 2 devices on a network.
What are the layers implemented by?
apps
oses
network cards
networking hardware
What is the application layer for?
This is the layer that the users actually interact with. Applications or processes handle data from lower layers and make use of it.
What is the presentation layer for?
This is the syntax processing layer. Converts received data into required format for the application or for transmission (typically a secure format).
What is the session layer for?
Establishes, maintains and synchronises interaction between 2 communication devices / apps / processes. It also handles authentication and authorization.
Also responsible for reconnecting processes/apps.
What is the transport layer for?
Adding certain bits to the data so that it can be transmitted across network connections. Common protocols include TCP and UDP.
