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Packet Switching
Connectionless: No connection is established when data is transmitted
Data is fragmented into smaller, more manageable chunks called packets
Packets are individually addressed and sent to intended destination
Receiving computer waits for all packets and reassembles packets into original message before delivering message to upper level
Network layer in the Internet is packet-switched, regardless of connection-oriented or connectionless transport methods (TCP/UDP)
Advantages
Circuit Switching
Packet Switching
Provides a consistent and reliable connection with a fixed bandwidth
More efficient use of network resources since packets can be routed based on current network lfoad
Data arrives in order and does not need to be reassembled
More secure as it is harder to intercept data since different packets can take different paths to destination
TCP/IP Layering
Modularity: Each layer focuses on a specific function, making the system easier to design, understand and troubleshoot
Interoperability: Standardised layer functions and interfaces allow devices and software from different vendors to work together
Flexibility: Improvements can be made in one layer without affecting other layers
Troubleshooting: Network issues can be diagnosed layer by layer
Standardisation: Common language and framework
DHCP
DHCP assigns IP addresses to devices on the local network
Discover: client broadcast to look for a DHCP server
Offer: DHCP server offers an address
Request: client requests to release the address
Acknowledge: DHCP server sends the address to the client for acknowledgement
DNS
DNS translates human-readable domain name to machine-readable IP address