Networking
Networking:
- A stand alone computers is one that is separate and unconnected from others
- A network is a set of connected computers that share data or resources
- The Internet is a network
Pros:
- sharing of resources and peripherals,
- share data and work together,
- easy backups
Cons:
- Can become dependent on the network,
- downtime- Could lose money in a company.
- low levels of security
- There are higher rates of traffic which reduces performance
- Protocols are needed in order to allow all computers can communicate with different hardware
- A protocol is a set of rues relating to the communication between devices
- TCP/IP (Transmission Control Protocol Internet Protocol) used to transfer all packets across the Internet and error free packet switching
- FTP (File Transfer Protocol), or HTTP, or SMTP
TCP/IP, DNS, Layering:
- Protocols have layers which each have a different job
- OSI model has 7 models on how to structure a protocol. Physical layer, Data link, network, transport, session, presentation, application
- Data will pass through all layers of a protocol
- TCP/IP does not have a session or presentation layer
- DNS allows resources to be named on a network and is built into TCP/IP
- DNS replaces IP addresses with a user friendly name eg google.co.uk and when a resource is requested the DNS converts the URL to the IP address
LAN and WAN:
- Local area network is over a small geographical area and owned by a company and maintained by a company
- Wide area network is over a large geographical area
- You can connect to a network over wireless or wired connections
- A NIC is needed for a computer to connect and communicate with a network each with a unique MAC address which is fixed
- An IP address can change so is a logical address
Client and Peer to Peer:
- In a client server model, the clients request services from the server, used in school
- In a peer to peer model all computers have equal status and communicate with each other, very cheap to implement
- Peer to Peer allows easy file sharing eg bit torrent
Packet Switching:
- Method of transmitting data over a network
- In circuit switching a fixed route is established between two nodes before data transmission begins, all data will be transmitted along this route before releasing the connection, this is an old way of exchanging data and insecure
- In packet switching the data is broken up into packets, which are sent along individual random routes to the destination and may arrive out of sequence so needs to be reassembled at the destination. this is more efficient and more secure
- A protocol is a set of rues relating to the communication between devices
- TCP/IP (Transmission Control Protocol Internet Protocol) used to transfer all packets across the Internet and error free packet switching
- FTP (File Transfer Protocol), or HTTP, or SMTP
TCP/IP, DNS, Layering:
- Protocols have layers which each have a different job
- OSI model has 7 models on how to structure a protocol. Physical layer, Data link, network, transport, session, presentation, application
- Data will pass through all layers of a protocol
- TCP/IP does not have a session or presentation layer
- DNS allows resources to be named on a network and is built into TCP/IP
- DNS replaces IP addresses with a user friendly name eg google.co.uk and when a resource is requested the DNS converts the URL to the IP address
LAN and WAN:
- Local area network is over a small geographical area and owned by a company and maintained by a company
- Wide area network is over a large geographical area
- You can connect to a network over wireless or wired connections
- A NIC is needed for a computer to connect and communicate with a network each with a unique MAC address which is fixed
- An IP address can change so is a logical address
Client and Peer to Peer:
- In a client server model, the clients request services from the server, used in school
- In a peer to peer model all computers have equal status and communicate with each other, very cheap to implement
- Peer to Peer allows easy file sharing eg bit torrent
Packet Switching:
- Method of transmitting data over a network
- In circuit switching a fixed route is established between two nodes before data transmission begins, all data will be transmitted along this route before releasing the connection, this is an old way of exchanging data and insecure
- In packet switching the data is broken up into packets, which are sent along individual random routes to the destination and may arrive out of sequence so needs to be reassembled at the destination. this is more efficient and more secure
No comments:
Post a Comment