Transcript protocol - Digitalist

3 Computing System
Fundamentals
3.4 Networked Computer Systems
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3.4.3 Network Protocols
WANs vs. LANs
• They differ in size, but also:
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LAN's allow networked machines to listen
and broadcast freely, with switches and
bridges keeping the traffic manageable,
WANs however use software switching
technology to direct the traffic.
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WANs vs. LANs
• They differ in size, but also:
‣
‣
LAN's allow networked machines to listen
and broadcast freely, with switches and
bridges keeping the traffic manageable,
WANs however use complex software
switching technology to direct the traffic.
4
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Protocols
A protocol is a universally standard set of rules
governing how devices communicate.
It must include information on:
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handshaking (establishing the connection),
data compression methods,
end of message markers,
confirmation of receipt,
error checking methods.
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Protocols
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The commonest example on the internet is TCP/IP.
The decision on which to use is based on speed,
security, accuracy, reliability, simplicity, etc. e.g.
Skype uses UDP because it is faster than TCP/IP.
Essential both devices are capable of using the
same protocol (very likely these days).
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