What Internet port speed to choose for an office of 20-25 people?

Question

Computer networks

Load:
1) ip-telephony via Bitrix
2) all sorts of office applications.
They offer 25 Mbps.
Enough, what do you think?
added:
Now they are connected to some common line of 50 Mbps, this is how the speedtest gives out, but it is impossible to work during busy hours.

Answer 1

10 Mbps is enough for you. I have one office (~ 70 people) sitting on a 10 Mbps channel. It all depends on how correctly to cut the channel. You need a gateway that will cut the speed according to the type of traffic: cut it to a minimum or prohibit parasitic traffic and reserve the bandwidth for important traffic. Also not unimportant factor is the restrictions on the use of applications not approved by the administrator.
If you don’t set up shaping, then even 50 Mbps for 5 people may not be enough for you if someone from the office starts a torrent download or starts watching 4K video.

Answer 2

Measuring speed in "people" is not entirely correct.
Work tasks, call volume, remote work (including offsite clouds) - all this greatly affects the channel needs.
And for an average question, you can only get an average answer - for the working needs of an average office, the calculation starts from 1 megabit per person.

Answer 3

If the accountant and in general office plankton - yes, that's enough.

Answer 4

Enough.
The presence of a problem at 50Mbit indicates either specific requirements that you are silent about, for example, file 1C on a remote server without RDP.
Or that someone usurps the channel, as a rule, this can be done with videos, games, torrents.
These problems are solved by setting QOS.

Answer 5

For such a solid organization, I would set the speed to 300 Mbps so that everyone can work comfortably.