Question : round robin dns with multiple webserver

Hi
i was looking to a dns report which belongs to www.brighttalk.com
and i am little bit of confused the way it has been done. so i need some one to explain me,

inistailly with dnsstuff.com  , dns report its comes up like this

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WWW Record : www.brighttalk.com. CNAME beta.brighttalk.com.edgesuite.net. [TTL=14400]

Domain A Lookup: brighttalk.com. A 80.169.120.131 [TTL=600]

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but if check this domain with http://www.checkdns.net, it will come up like this

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DNS round-robing with multiple web servers detected
  Checking HTTP server www.brighttalk.com [195.49.93.202]

  HTTP server www.brighttalk.com[195.49.93.202] answers on port 80
  Received: HTTP/1.1 200 OK (Server: Apache) . . BrightTALK: Webcasts Worth Watching | www.brighttalk.com. . . . . . . . . . . @import /sites/all/themes/dotcom/print.css;. . @import /sites/all/themes/dotcom/style/page.css;. . @import /sites/all/themes/dotcom/style/jquery.cluetip.css;. . @import /sites/all/themes/dotcom/style/modul
  Checking HTTP server www.brighttalk.com [195.49.93.207]
 

 HTTP server www.brighttalk.com[195.49.93.207] answers on port 80
  Received: HTTP/1.1 200 OK (Server: Apache) . . BrightTALK: Webcasts Worth Watching | www.brighttalk.com. . . . . . . . . . . @import /sites/all/themes/dotcom/print.css;. . @import /sites/all/themes/dotcom/style/page.css;. . @import /sites/all/themes/dotcom/style/jquery.cluetip.css;. . @import /sites/all/themes/dotcom/style/modul

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So according to dnscheck.com, it has 2 webserver with round robin
but with dnsstaff.com , it has one webserver which is  80.169.120.131, even if you ping to brighttalk.com, it will show this ip
 80.169.120.131

now i am fully confused.. why 2 dns report showing 2 things ???  

Answer : round robin dns with multiple webserver

They're entirely different records.

One is:

brighttalk.com.  IN A  

The other is:

www.brighttalk.com.  IN CNAME  beta.brighttalk.com.edgesuite.net.

While you'll find in many cases the two variants (with and without www) point to the same thing there's no reason or rule that says they must.

Chris