The venue said they had fibre. That tells you nothing.

The venue told you the room has fibre. It probably does. That still tells you almost nothing about whether your livestream will hold, because the number that matters is not the speed of the building's connection, it is the speed your encoder can actually sustain out of your room, at the hour of your event, with everyone else in the building using it too.

Those are different numbers. They are frequently different by a factor of five.

If you only take one thing from this: get the sustained upload figure, measured on a weekday at the hour your event runs, on the specific drop in the specific room. Not the building's advertised circuit. Not a Sunday morning test. If nobody will give you that, assume the connection is unusable and plan a path of your own.

Why the speed test lies

A speed test measures a burst. It grabs as much capacity as it can for a few seconds on an otherwise idle circuit and reports the peak. That is a genuinely useful number for a person deciding whether to stream a film tonight.

It is close to worthless for a three hour broadcast.

Your stream does not want a burst. It wants the same bitrate every second for the entire event, and it degrades in a specific ugly way when it cannot get it: the encoder buffers, then drops frames, then the platform steps your viewers down to a lower quality, and if it gets bad enough the stream disconnects and the platform ends it. Viewers do not see a technical fault. They see a bad video and they leave.

So the question to a venue is never "how fast is the internet." It is "what will this drop sustain, for three hours, on a Tuesday at two."

The four questions that actually separate venues

Most of what goes wrong is knowable in advance from four answers.

Is the drop in the room, or does the cable run from somewhere else? A hardline in the ballroom and a hardline in the business centre three floors away are both "a hardline." Only one of them is any use to you.

Is that circuit shared? With guest wifi, with point of sale, with badge scanners, with the building's own overnight backups that sometimes do not finish. A dedicated VLAN is worth asking for and worth putting in the contract.

Is there another event in the building that day? This is the question almost nobody asks and it is the one that has ended the most streams. Two ballrooms, one uplink, and the other event brought their own streaming crew.

Does the building have cellular coverage in the actual room, on more than one carrier? Because that is your backup, and a basement ballroom with no signal means you do not have one.

Wifi is not an option, and this is not a preference

There is a polite version of this where you weigh the tradeoffs. Here is the real one: do not stream a paid or professional event over wifi. Not guest wifi, not the staff network, not a dedicated access point the venue sets up for you.

Wifi is a shared medium with no guaranteed throughput. A room with four hundred phones in it behaves nothing like the same room empty, and the failure is not gradual. You will test at eleven, everything will look fine, and you will lose the stream twenty minutes into the keynote when the room is full.

Hardline ethernet, on a circuit you have some claim to, with a cellular bond on a genuinely different path out of the building. That is the setup. Everything else is a gamble where you find out you lost it in front of an audience.

How much you actually need

Less than people assume, and more than the venue quotes.

A 1080p30 broadcast with speech audio sends roughly 6.1 Mbps. That is the encoder's output. What you book is about double it, because a circuit running at its limit has no room to absorb anything else, and something else always turns up.

We put the arithmetic in a bandwidth calculator so you can run your own numbers, including what happens when you add a second destination or a backup encoder on the same circuit. The short version is that the headroom multiplier matters more than any of the codec choices people spend their time on.

What to do when the answer is bad

Sometimes you ask all of this and the answer is that the venue has one shared circuit, no dedicated drop, and no cellular in the room. That is not the end of it.

Bond cellular from wherever in the building does have signal and run a cable. Bring a Starlink terminal if there is sky access and time to set it up. Record locally at full quality and publish afterwards, streaming a lower bitrate live, which is often the honest answer for a room that genuinely cannot support the broadcast anyone imagined.

What you do not do is turn up hoping. The reason to ask these questions six weeks out rather than on the morning is that every one of those fixes takes planning, and none of them can be arranged at eight in the morning on event day.