We have a two story building office and we are going to upgrade our internet connection. Is it better to have two separate internet connection with 15mbps each for first floor and second floor or just a single internet connection with 30mbps bandwith?
I would say that a single connection of 30mpbs would be better for the following reasons:
Less chance a high usage burst is going to fill the pipe during peak times. If one floor's usage capacity is much higher, it is more likely that the 15mbps would get saturated vs the 30mbps.
Monitoring and Control - Unless you have hardware to terminate both connections, the second internet connection will require additional hardware and security monitoring.