How fast is the internet in your building, really?

An office building is offered with the text "Fiber optic available." That sounds good. For many tenants and landlords it's even a reason not to ask any further questions about the digital infrastructure. Yet that one sentence says surprisingly little about how the internet in the building ultimately performs.

Compare it to a highway in front of the door. There's asphalt, fine. But how many lanes are available? How much traffic is already using it? And do the roads inside the building actually connect to that highway? The speed at the front door doesn't tell you how fast things work on the inside.

In this article we explain in plain language what terms like Mbps, Gbps and fiber optic mean, why a fast connection can still feel slow, and which questions you should ask before renting, leasing out or buying a building.

Mbps and Gbps: speed in plain language

Internet speed is usually expressed in Mbps (megabits per second) or Gbps (gigabits per second). The conversion is simple: 1 Gbps equals 1,000 Mbps. The higher the number, the more data can be processed at the same time.

You can think of Mbps as the number of lanes on a digital highway. More lanes mean more traffic can pass at once without congestion. For an organization with many simultaneous users, video meetings and cloud software, that capacity matters a great deal.

Important to remember: speed is not the same as quality. Besides raw speed, latency (delay), stability, packet loss (data lost along the way) and upload capacity all determine how pleasant the internet feels in practice. A connection can look fast on paper and still feel unreliable.

An indication of speeds and use

The table below gives a general picture. It is explicitly not a standard; the speed you need always depends on your specific situation.

Which speed fits depends on the number of users, the type of organization, the degree of cloud use, video conferencing, AI applications, IoT, camera security, working with large files and, not unimportant, your expected growth. What is plenty today may be tight in three years.

Download and upload: two directions on the highway

Internet traffic moves in two directions. Download is data coming toward the user: opening websites, streaming, retrieving files and launching cloud applications. Upload is data going out from the building: video calling, uploading files, cloud backups, camera footage and collaborating in the cloud.

Many consumer connections have high download speeds and low upload speeds. For modern organizations that's often not ideal. Once employees spend the whole day on video calls, collaborating in the cloud and sharing large files, upload becomes at least as important as download.

That's why business fiber optic is often more attractive when both directions are equally fast. This is called a symmetrical connection: for example, 1 Gbps download and 1 Gbps upload. As work shifts to the cloud and real-time collaboration, symmetry becomes an increasingly logical requirement.

A building can have a fast connection at the front door and still feel sluggish inside. The question is not whether there is internet, but how much capacity the building actually lets through.

Fiber optic is not automatically fast

Fiber optic is first and foremost an infrastructure technology: a way of transporting data. Over that same fiber, a provider can deliver very different speeds: 100 Mbps, 500 Mbps, 1 Gbps, 10 Gbps or even higher.

In other words: "Fiber optic available" says something about the infrastructure present, but nothing yet about the actual capacity. It's entirely possible that fiber is in place while only a modest subscription is connected to it, or that the connection has been installed but is not yet active. This is exactly why the first question many modern tenants ask now concerns the internet connection that is actually present.

Always ask the follow-up questions: which speed is available, is the connection active, is it symmetrical, and are there multiple providers to choose from? You can read more on this topic in our overview on fiber optic in buildings.

The internal infrastructure plays a role too

The connection outside the building is only part of the story. Once the data comes in, it has to pass through the internal infrastructure: the cabling, the switches, the patch panels, the network equipment and the Wi-Fi. Each of these components can slow down a fast connection.

Take a building with a 1 Gbps fiber connection, while parts of the internal cabling still operate at 100 Mbps. In that case the external connection is not the bottleneck. The problem lies inside the building itself. Old CAT5 cabling, outdated switches, poorly organized patch panels or misconfigurations all have the same effect: they choke the speed.

In short: a Ferrari on a dirt road stays slow. The fastest connection in the world delivers nothing if the internal network can't process that speed.

Cabling in brief

The type of internal cabling largely determines what's possible inside a building. The values below are indicative; actual performance depends on distance, installation quality, equipment and configuration.

Wi-Fi is not the same as internet

"The internet is slow," we often hear. Even though the internet connection itself may well be fine. The problem then doesn't lie outside, but in the way the signal is distributed inside.

Common causes include poor Wi-Fi coverage, too few access points, interference, too many users on a single access point or outdated Wi-Fi equipment. In all these cases, the connection isn't the problem, the last few meters to the user are.

Remember the distinction: internet is the connection to the outside world, Wi-Fi is just one way of using that connection inside the building. Anyone who takes Wi-Fi coverage in the building seriously prevents a good connection from unnecessarily feeling slow.

How much speed does an organization need?

There is no universal answer, but a practical breakdown helps establish an order of magnitude. Treat the following figures as indications, not fixed standards.

• Small office (roughly 2 to 10 users): 100 to 500 Mbps is often sufficient.
• Medium-sized office (roughly 10 to 50 users): 500 Mbps to 1 Gbps is often sensible.
• Larger digital organization (heavy cloud, video, data and AI use): 1 Gbps or higher becomes increasingly relevant.

More important than the exact number is whether the infrastructure can grow along with demand. A connection that fits today should still be sufficient in five to ten years, or easy to scale up.

Data consumption is growing, including from the building itself

It's not only employees who use data. The building itself now consumes increasing amounts of capacity. Think of IoT sensors, cameras, access control, energy management, charging infrastructure and building management systems. All these systems continuously communicate over the network.

This is known as the data consumption of the building. As buildings become smarter, this consumption steadily grows. You can read more about this in our article on smart buildings and their digital foundation.

On top of that comes AI. AI applications, cloud software, real-time collaboration and increasingly large data files raise the need for stable and scalable connections. The question "Is your building AI-ready?" therefore isn't just about software. The infrastructure has to physically handle the growth, from the cable to the switch.

What should a tenant or owner know?

For a well-founded decision, at least the following should be known about a building. This checklist helps you look beyond "there is internet."

• which providers are available;
• whether fiber optic is present and active;
• which speeds can be delivered;
• whether upload and download are symmetrical;
• whether redundancy is possible;
• which type of internal cabling is present;
• what capacity the switches can handle;
• how the Wi-Fi is set up;
• where the MER and SER are located;
• how easily the infrastructure can be scaled.

Anyone who has these points mapped out can judge a connection not just on speed, but on whether the building can actually deliver on that speed. Redundancy is part of this too: we explain why a single connection is sometimes not enough in our article on network redundancy.

From speed to digital delivery level

IT-Label looks beyond the question of whether there is internet. Instead of a single number, the methodology assesses the full digital delivery level of a building: external connectivity, internal infrastructure, cabling, Wi-Fi, MER and SER, redundancy, scalability, monitoring and digital security.

The idea behind it is simple: not just measuring how fast internet comes in, but examining how much digital capacity a building can genuinely deliver. This translates into a classification from PREMIUM to SHELL, allowing different buildings to be compared in the same way. This way, an invisible property of real estate suddenly becomes visible, comparable to a digital MOT.

Frequently asked questions

Why is my internet slow even though there is fiber?

The bottleneck is often in the building itself. Old cabling, outdated switches, poorly organized patch cabinets, incorrect configuration or poor Wi-Fi can slow down a fast connection.

Which network cable do I need for 1 Gbps?

CAT5e reaches up to about 1 Gbps and CAT6 reaches 1 Gbps, while CAT5 often only reaches up to 100 Mbps. CAT6A goes up to 10 Gbps; actual performance depends on distance, installation and equipment.

Is a fast connection also a good connection?

Not always. Besides speed, latency (delay), stability, packet loss and upload capacity also determine how well the internet works in practice.

What is a symmetrical internet connection?

A connection that is equally fast in both directions, for example 1 Gbps download and 1 Gbps upload. That is useful for organizations that make a lot of video calls and collaborate in the cloud.

How do I find out what the internet in a building can really do?

Ask about the providers, whether fiber is active, the available speeds, the cabling, the switches and the Wi-Fi. An IT-Label pre-inspection maps this out objectively.

A concrete next step

The question isn't only: do we have internet? The real question is: what can this building handle digitally? Speed is just one part of digital quality. A future-proof building is also stable, scalable, secure, documented and redundant where needed.

If you want to know what a building can truly deliver, an objective measurement is the logical first step. With an IT-Label pre-inspection you map out the digital baseline, with an IT-Label certification you record the delivery level, and in the case of acquisition or sale, a Digital Due Diligence gives certainty about what you're buying digitally.

IT-Label. Together we make visible what is still invisible today. For more information, visit www.it-label.com.