iwmw 1997: networking for webmasters
TRANSCRIPT
© The JNT Association 1997
Networking for WebMasters
John MacCullochUKERNA
J.MacCulloch @ ukerna.ac.uk
© The JNT Association 1997
Web Components
Server
Hypertext InformationBase
HTML
Client
Display
Hypertext Transfer ProtocolHTTP
Network
© The JNT Association 1997
Typical Networks
Road
Rail
Telephone
National Grid
Canal
Airline
Old Boy / Old Girl
Computer
Postal
Underground
Radio / Television
Mobile Telephone
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What is a Network
Infrastructure which enables computer systems ( and people ) to inter communicate
© The JNT Association 1997
What is a Network
Infrastructure which enables computer systems ( and people ) to inter communicate
© The JNT Association 1997
What is a Network
Infrastructure which enables computer systems ( and people ) to inter communicate Network
© The JNT Association 1997
What is a Network
Infrastructure which enables computer systems ( and people ) to inter communicate
JANET
MAN
MAN
© The JNT Association 1997
Network Performance
BandwidthMBits / SecHow many bits/sec can be got across the
network ( cars / hour over the mororway )
Latency m SecsHow long from A to B
Jitter m SecsVariation in Latency
© The JNT Association 1997
Network Classifications
Size LAN MAN WAN
Access Public Private
Protocol Open Proprietary
Timing Synchronous Asynchronous
Topology Star Ring Bus Tree Mesh
Switching Packet Circuit
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Network SizeLAN MAN WANLocal Metropolitan WideCampus City Country
NetworkMAN
MAN
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Network Timing
SynchronousData bits are timed
by a clock pulse
AsynchronousData bits are
transmitted as required
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Asynchronous Under Load
Load
LatencyJitter
Zero Max
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Network TopologyStar
Ring
Bus
Tree Mesh
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Network Switching
Circuit Switchingdedicated connection
established between end points which remains in place for the duration of the call
Packet Switchinginformation packets are
individually routed through the network
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Network Functions
Ping
Traceroute
File Transfer
Terminal Access
Electronic Mail
Usenet News
Video
World Wide Web
© The JNT Association 1997
Example Page
Raw Text 1 KHTML 2 K+ graphic 40 KPostscript 100 KPS ( 300dpi ) 1,000 K
John MacCulloch
Since graduating John hasexperienced twenty five years in computingcovering the roles of operations,programming, design, analysis, support,and management.
Immediately prior to his joining UKERNAhe spent nine years as Head of ComputerServices at King Alfred's College inWinchester, where he expanded the userbase from fifteen to over three hundred. Heinitiated networking and extended the LANconnectivity by installing a JANETconnection.
John hosted the JANET User SupportWorkshop in September 1994.
Contacting Information E-Mail: [email protected] Telephone: 01235 822250
Fax: 01235 822399 Snail Mail: UKERNA
Atlas CentreChilton, DIDCOTOxfordshireOX11 0QS
John MacCulloch
Copyright © The JNT Association. All rights reserved.
© The JNT Association 1997
Law’s Law
A picture may be worth a thousand words but a JPEG file takes longer to transmit.
Derek Law, Director of Information Services and Systems at Kings College
© The JNT Association 1997
Hints
Look at your site through different eyesdifferent clientsdistant location or simulate low bandwidth
Promote UK based search enginesNote Law’s LawUse right graphic type ( .gif .jpeg )Remember Web is Client Pull
© The JNT Association 1997
Questions
© The JNT Association 1997
Networking for WebMasters
John MacCullochUKERNA
J.MacCulloch @ ukerna.ac.uk