Web

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• Web
• Performance
• Modeling

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Client
Server
LAN
LAN
Network
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Servers
A
C
D
Clients
B
Network
...
E
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(No Transcript)
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Client Side ModelsNo cache proxy server case
Client 1
Client M
LAN
Router
Internet
Webserver
Webserver
6
Client Side ModelsNo cache proxy server case
Outgoing link
Clients
LAN
4
1
2
3
Router
Internet web server
5
6
Incoming link
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Web Proxy Architecture
Clients
Proxy Server
Servers
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Example with Proxy Cache Server
Clients
Proxy Server
External Web Servers
. . .
router (50msec/packet)
Internet
LAN (10 Mbps Ethernet)
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Client Side Models Cache proxy server case
Client 1
Client M
LAN
Proxy Cache server
Router
Internet
Webserver
Webserver
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Client Side ModelsCache proxy server case
Outgoing link
LAN
4
1
2
3
Clients
Router
Internet web server
5
7
6
CPU
Incoming link
8
Disk
Proxy cache server
11
Cache Hit
outgoing link
clients
router
LAN
ISP Internet web server
cpu
incoming link
disk
proxy cache server
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Cache Miss
outgoing link
clients
router
LAN
ISP Internet web server
cpu
incoming link
disk
proxy cache server
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Web Server Example
6 HTTP req/sec
Web server
router (50msec/packet)
10 Mbps Ethernet
T1 link
ISP
Internet
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Single Web Server
Web server
LAN
Router
Internet
Client
Client
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Single Web Server
LAN
Incoming link
Router
3
1
2
Web Server
4
cpu
6
disk
5
Outgoing link
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Single Web Server
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Mirrored Web Serverswith a shared file system
Web server n
Web server 1
File server
LAN
Router
Internet
Client
Client
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Mirrored Web Serverswith Shared file system
LAN
Incoming link
Router
3
1
2
Web Server 1
Web server n
4
5
cpu
cpu
6
6
Outgoing link
Disk farm
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Mirrored Web Serverswith Shared file system