Domain Name Resolution with the Domain Name System

“I want to visit abc.com.”

http://abc.com“Please find abc.com and

show it to me.”

“Do we already know where abc.com is?”

“Yes. Here’s the IP address

for abc.com:

12.231.87.9.”

Caching Name Server

Operated by ISP

Web Server hosting the

abc.comweb site

at IP address

12.231.87.9

ISP (BellSouth)

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Domain Name Resolution with the Domain Name System

“I want to visit abc.com.”

http://abc.com“Please find abc.com and

show it to me.”

“Do we already know where abc.com is?”

“No. We need to look that up. Root

server, can you help us?”

Caching Name Server

Operated by ISP

Root Serve

r

Web Server hosting the

abc.comweb site

at IP address

12.231.87.9

Name Server

xyz.net atIP address

43.75.241.2

ISP (AOL)

“The name server xyz.net has the IP address of

abc.com. Here’s the IP address of that name

server: 43.75.241.2. Talk to it.”

“Here’s the IP address of abc.com:12.231.87.9

.”

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“OK, name server at 43.75.241.2, what’s the IP address for abc.com?”

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