Scanning machines on a network

[Dar Scott]

On Sunday, March 10, 2002, at 01:54 PM, Dar Scott wrote:

> On Sunday, March 10, 2002, at 12:00 PM, Richard Gaskin wrote:
>> A lot of software packages scan the local network to see if other 
>> copies of
>> the software may be running with the same serial number.
>>
>> I've thought of many ways to accomplish this, but all of them 
>> seem slow and
>> inefficient.
>
> Here is an idea.  Invert the idea of scanning.  Each copy UDP 
> Broadcasts its serial number at startup and every minute or so to 
> a obscure port of your choosing, eg. 255.255.255.255:47011.  Each 
> copy also listens on that port.  If a serial number comes in from 
> a different computer that matches that of the listening copy, 
> there's a serial number clash.

My tinkering with Revolution has gotten to UDP.  I have been able 
get UDP working, so I think the above can be done in Revolution.  
However, I don't have a way to get the local IP, yet.  (Receiving 
UDP is weird; at least it is the way I did it.)

Dar Scott