Important Diagrams
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By: M. Zeeshan Ali
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Distributed Denial of Service Attack
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Distributed Denial of Service Attack
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Distributed Denial of Service Attack
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Distributed Denial of Service Attack
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Data Interception
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Data Interception
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Data Interception
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Data Interception
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Pharming
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Pharming
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Pharming
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Pharming
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Role of Router
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Role of Router
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Role of Router
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Role of Router
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Process to connect the device to the internet
and requesting a webpage
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Process to connect the device to the internet
and requesting a webpage
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Process to connect the device to the internet
and requesting a webpage
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Process to connect the device to the internet
and requesting a webpage
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Process to open a secured webpage on the
device
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Process to open a secured webpage on the
device
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Process to open a secured webpage on the
device
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Process to open a secured webpage on the
device
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Process to open a secured webpage on the
device
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Process to open a secured webpage on the
device
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Virtual Memory
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Virtual Memory
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Virtual Memory
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Virtual Memory
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Virtual Memory
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Operations of Firewall
Internet
Firewall examines
all incoming and
outgoing data
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Firewall
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Internal Network
Operations of Firewall
Internet
Transmission is rejected
if data is not according
to the set criteria.
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Firewall
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Internal Network
Operations of Firewall
Internet
Firewall also maintains
log of all incoming and
outgoing data for later
interrogation.
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Firewall
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Internal Network
Operations of Proxy Server
Proxy server works as an
intermediary between
client and internet
Internet
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Request
User
192.168.1.123
Request
Proxy Server
Internal Network
User
192.168.101.100
Operations of Proxy Server
Proxy server receives request from
clients, and checks if the requested
page is stored in its cache.
Internet
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Request
192.168.1.123
User
192.168.1.123
Request
cache
Proxy Server
Internal Network
User
192.168.101.100
Operations of Proxy Server
Internet
Request
202.123.1.125
If requested page is not available in
cache; proxy server forwards request
on internet using its own IP address.
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Request
192.168.1.123
User
192.168.1.123
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cache
Proxy Server
202.123.1.125
Internal Network
User
192.168.101.100
Operations of Proxy Server
Internet
Proxy server stores frequently visiting
webpages in its cache, and sends it to
the client when requested.
Request
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HTML document
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HTML
document
User
192.168.1.123
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cache
Proxy Server
202.123.1.125
Internal Network
User
192.168.101.100