Status codes

Staus codes:-

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Informational
Code :-100
Phrase :- Continue
Description:-The initial part of the request has been received , and the client may continue with the request.

Code :- 101
Phrase :- Switching
Description :- The server is complying with a client request to switch protocols defined in the upgrade header.

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Success
Code :- 200
Phrase :- OK
Description :- The request is successful

Code :-201
Phrase :- Created
Description :- A new URL is created .

Code :- 202
Phrase :- Accepted
Description :- The request is accepted , but it is not immediately acted upon


Code :- 204
Phrase :-  No content
Description :-There is no content in the body

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Redirection


Code :- 301
Phrase :- Moved permanently
Description :- The requested URL is no longer used by the server.


Code :- 302
Phrase :- Move temporarily
Description :- The requested URL has moved temporarily.


Code :- 304
Phrase :- Not modified
Description :-The document has not been modified.

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Client Error

Code :- 400
Phrase :- Bad request
Description :- There is a syntax error in the request.


Code :- 401
Phrase :- Unauthorized
Description :- The request lacks proper authorization.


Code :- 403
Phrase :- Forbidden
Description :- Service is denied .


Code :- 404
Phrase :- Not found
Description :- The document is not found.


Code :- 405
Phrase :- Method not allowed
Description :- The method is not supported in this URL.


Code :-  406
Phrase :- Not acceptable
Description :- The format requested is not acceptable.
 

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Server Error

Code :-500
Phrase :- Internal Server error
Description :- There is error , such as a crash , at the server site.

Code :- 501
Phrase :- Not implemented
Description :- The action requested cannot be performed.

Code :- 503
Phrase :-  Service unavailable
Description :-The service is temporarily unavailable ,but may be requested in the future.
 

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DNS in the Internet

DNS is  a protocol that can be used in different platforms.

In the Internet the Domain Name Space is divided into three different sections :

1) Generic domains

2) Country domains and

3) The Inverse domains

1) Generic domains:-
The generic domains define registered hosts to their generic behavior.

Generic domain labels are as follow:-

aero :-   Airlines and aerospace companies

biz    :-   Businesses or firms

com   :-   Commercial organizations

coop   :-  Cooperative business organizations

 edu    :-  Educational institutions

gov      :-  Government institutions

info     :-   Information service provides

int       :-  International organizations

mil      :-  Military groups

museum :- Museums  and other non profit organizations

name    :-  Personal names (individuals)

net      :- Network support  centers

org     :-  Non profit organizations

pro     :-  Professional individual organizations


2) Country domains:-
The country domains section uses two - character country abbreviations.
Example :-
us  :-  United States

in  :-   India

uk  :- United Kingdom

Second labels can be organizational ,or they can be more specific , national designations.
The United States ,for example , uses state abbreviations as a subdivisions of us example ca.us


3) Inverse domains:-
The inverse domain is used to map an address to a name .the convention of reading domain labels from bottom to top ,an IP address such as 132.34.45.121 is read as 121.45.34.132.