Link Testing: It is the process of testing the functionality of the each and every links using TOOLS is link testing.

there are applications which contains 'n' number of links. Testing them manually is a time cosuming job. Hence we use tools which perform link testing very fast & accurate.

There are many tools available for performing link testing which includes:
1. Xenu link sleuth
2. Web Link Validator
3. Link Scan
4. Free Link Checker etc

We are discussing here about the Xenu tool

Q: How to download the xenu?
Ans:
 -> Go to google & search "Download Xenu"
 -> Click on the first official link
 -> click on the download icon
 -> Some time it opens advertisement popup, there you need to click botton link "No thanks, continue to download Xenu's Link Sleuth"
 -> Click on download icon again
 -> Download the .zip file
 ->extract the .zip file, you will get setup.exe file. Double click and install the setup.exe file


About Tools:
This tool has following features:

1. Filter: What are the websites you have to include to test the links OR what are the websites you dont want to include

2. Threads: Number of links the tool has to test at a time

3. Depth: How many navigatations OR steps required to complete the functionality is k.a., depth.

4. Report types

5. Authentications



In link testing we find following type of defects:
1. Broken Link: The requested page is not present OR has not opened.
Ex:404 error OR 403 forbidden

2. Orphon link: The link with downloadable content is missing

When you run the tool, we may find some errors link "Forbidden error"
This is not a defect. This indicates a user input is required to navigate to next page.

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Q: How the tool works:

1. It will find the links present in the website
2. It will read the links and send a request to the server
3. Server will validate the request, if every thing is fine then server will return the response code.
4. this tool reads the response code received from the server and based on that it decides the status




Response codes:
100 Series: Informational responses (100 – 199)

100 Continue
101 Switching Protocols
102 Processing



#2) 200 Series: Successful responses (200 – 299)
The client accepts the Request, being processed successfully at the server.

200 – OK
201 – Created
202 – Accepted
203 – Non-Authoritative Information
204 – No Content
205 – Reset Content
206 – Partial Content
207 – Multi-Status
208 – Already Reported
226 – IM Used


#3) 300 Series: Redirection messages (300 – 399)
Most of the codes related to this series are for URL Redirection.

300 – Multiple Choices
301 – Moved Permanently
302 – Found
303 – Check Other
304 – Not Modified
305 – Use Proxy
306 – Switch Proxy
307 – Temporary Redirect
308 – Permanent Redirect


#4) 400 Series: Client error responses (400 – 499)
These are specific to client-side error.

400 – Bad Request
401 – Unauthorised
402 – Payment Required
403 – Forbidden
404 – Not Found
405 – Method Not Allowed
406 – Not Acceptable
407 – Proxy Authentication Required
408 – Request Timeout
409 – Conflict
410 – Gone
411 – Length Required
412 – Precondition Failed
413 – Payload Too Large
414 – URI Too Long
415 – Unsupported Media Type
416 – Range Not Satisfiable
417 – Expectation Failed
418 – I’m a teapot
421 – Misdirected Request
422 – Unprocessable Entity
423 – Locked
424 – Failed Dependency
426 – Upgrade Required
428 – Precondition Required
429 – Too Many Requests
431 – Request Header Fields Too Large
451 – Unavailable For Legal Reasons


#5) 500 Series: Server error responses (500 – 599)
These are specific to the server-side error.

500 – Internal Server Error
501 – Not Implemented
502 – Bad Gateway
503 – Service Unavailable
504 – Gateway Timeout
505 – HTTP Version Not Supported
506 – Variant Also Negotiates
507 – Insufficient Storage
508 – Loop Detected
510 – Not Extended
511 –  Network Authentication Required