I am developing a LAN-based database application. It involves a central “server” app to house the database, along with many “client” applications that access it.
The “server” will be a simple C#-based HTTP server that responds to GET and POST requests. However, since it is designed to be able to run from any laptop on the network, I am wondering how to establish the connection between clients and the server without knowing the IP address.
I suppose I could ping every IP address from 192.168.0.0 to 192.168.0.255, and then test those that responded to see if any are my server. But I would only do that if there is no better way. Any suggestions?
Many of these types of discovery services run by putting out some kind of beacon on either the subnet broadcast address (for 192.168.0.0/24 it would be 192.168.0.255) or by putting out a beacon on a multicast address.
Multicast is particularly interesting because in a properly configured network, it allows hosts to find the service even across subnets. Routers and switches won’t generally forward broadcast packets across subnet boundaries, but multicast packets will.
The beacon would have information in it such as the port the service is running on, what type of service it is, whatever is needed to start using the service.