>>Hi,
>>
>>I have a customer where they use several of my ASP.NET applications (it is a large organization with multiple sites). I have always set each ASP.NET application as a separate site. One IT person didn't like it and here is what he did:
>>1. He created one site, lets call it 'DmitryApp_Multi_App'
>>2. He created a bunch of applications under this site. E.g. "Site1_App", "Site2_app" and so on.
>>3. Then when the main page from any of the Sites is to be used (URL) here is way he shows it (and it works):
>>
>> http://servername.theirorganizationname.org/Site1_app/MainPage.aspx
>>
>>I can't figure out and hence my question, how and where did he specify the part 'servername.theirorganizationname.org' ?
>>
>>TIA
>
>After I read on DNS, I would like to ask to confirm that my understanding is correct (and please correct me if I am wrong).
>
>Following the example above.
>
>1. On the customer Web Server I can get to the main page of, say, Site1_app using the following URL:
>http://servername/Site1_app/MainPage.aspx
>
>2. The IT manager showed me that I can get to the same page as:
>http://servername.theirorganizationname.org/Site1_app/MainPage.aspx
>
>Does it mean that he entered in the DNS Manager of their network a "map" (I am sure there is a correct term but I don't know it) that says
>"servername.theirorganizationname.org" = "servername" ?

'theirorganizationname.org' will be the external DNS which would map to the IP address of the server.
'servername' is a sub-domain of that server so the server is responsible for mapping that to another address.

>And if my understanding above is correct, he could have name it Anything, right? For example:
>"servername.johnsmith" = "servername" and therefore making the following URL work too:
>http://servername.johnsmith/Site1_app/MainPage.aspx

Possible - but not based on the 'servername.theirorganizationname.org' structure - it would need to be 'johnsmith.servername' (i.e. make 'johnsmith' a sub-domain of 'servername'. Just remember that host names are resolved from right to left.....