If you have just installed new Wi-Fi access points in your office, school or hospital, expecting everything to run much faster with the latest technology such as Wi-Fi 7, only to find that things are still slow after a few weeks, the problem is not the Wi-Fi. The problem lies in the cable that connects everything to the network. We have been using the Gigabit Ethernet port for more than twenty years, and it has fallen short of today’s needs. The good news is that there is an easy way to fix it: Multi-Gig, which delivers speeds of 2.5 and 5 Gbps over the same cabling you already have.

An invisible bottleneck

The most modern Wi-Fi access points, such as Wi-Fi 6, 6E and especially Wi-Fi 7, can transmit far more than 1 Gbps over the air. It is like having a four-lane motorway that suddenly narrows to a single lane. No matter how fast the motorway is, all the traffic grinds to a halt in that one lane. The logical step would be to move straight to 10 Gbps, but this has its drawbacks. To cover 100 metres you need Cat6A cable (with Cat6 you only reach about 55 metres), it consumes more power and the equipment is considerably more expensive. For this reason, it has rarely been deployed at the workstation.

The cabling found in most offices, hospitals and campuses is Cat5e and Cat6. In 2016, it was estimated that more than 70 billion metres had been installed. Replacing all this cabling means construction work, permits, service outages and, in historic buildings, is sometimes not even possible.

The solution: more speed without touching the wall

Multi-Gig was created to solve this problem. Equipment manufacturers joined forces in the NBASE-T and MGBASE-T alliances and developed the IEEE 802.3bz standard, approved in September 2016. The idea is simple: take the 10 Gbps technology and make it run at a lower speed, one that the existing cabling can support. In this way, the Cat5e and Cat6 cables already installed can reach speeds of 2.5 and 5 Gbps.

In addition, a Multi-Gig port adapts automatically. It negotiates the highest speed that the device at the other end and the cable can support, from 100 Mbps up to 5 Gbps (or even 10 Gbps on the most advanced models). If the cable cannot handle more, the speed usually drops rather than the connection being lost. That is why nothing needs to be changed; the same port that connects a laptop at 1 Gbps today can serve a Wi-Fi 7 access point at 5 Gbps tomorrow.

Data and power over the same cable

The most modern access points need not only more speed but also more power. With more antennas, several frequency bands and additional radios to monitor the spectrum, their consumption can exceed the 25.5 W offered by the traditional PoE+ standard. The IEEE 802.3bt standard, from 2018, raises this capacity to 60 W (Type 3) and 90 W (Type 4) over the same network cable, and it also works at speeds of 2.5, 5 and 10 Gbps.

For this reason, it is advisable to choose equipment that combines Multi-Gig and PoE++. If the port does not supply the power the access point needs, many devices disable features automatically and without warning, reducing performance without anyone understanding why.

Where the difference can be seen

• Wi-Fi 6E and Wi-Fi 7. This is the most obvious case. With Wi-Fi 7, each access point can handle much more traffic, and a 1 Gbps cable becomes a bottleneck precisely where it is needed most. Classrooms, auditoriums and busy meeting rooms.
• Demanding workstations. For tasks such as graphic design, video editing, medical imaging or laboratories handling very large files.
• Floor cabinets. To centralise traffic from surveillance cameras, sensors and shared storage, without needing to run fibre to each device.

What about the other options?

• Doubling up cables (2×1 Gbps). You have to run twice as much cable and use twice as many ports, and even so each individual download is still limited to 1 Gbps.
• Jumping to 10 Gbps. More expensive, with higher consumption and, often, new cable. It makes sense where the cabling already allows it, but not as a rule.
• Fibre to the device. Perfect for connecting floors and buildings, but it does not carry power. Each access point or camera would need its own power supply.

Four tips before taking the step

• Check the cabling. For 2.5 Gbps, Cat5e is a safe choice. For 5 Gbps, it is worth checking every connection, especially where many cables run together and may interfere with one another.
• Don’t forget the switch uplink. Multiple fast ports require uplinks that can keep pace (10, 25 or 40 Gbps). Otherwise, the bottleneck simply moves to another point.
• Calculate the power consumption. The power of each individual port is not enough; you have to add up the consumption of all the equipment at full load and consider redundant power supplies.
• Deploy in phases. A Multi-Gig switch installed today will still work with 1 Gbps equipment and will let you upgrade the access points to Wi-Fi 7 later, without having to touch the communications cabinet again.

Conclusion

Multi-Gig brings the wired network up to the speed level of today’s Wi-Fi. Each port multiplies its capacity by 2.5 or 5, supports high power delivery and makes the most of the cabling you already have. In short, you get more speed without the need for construction work.

At Teldat, the Windbit ESW8L3 (2.5 Gbps with PoE++) and ESW5L3 (multi-speed up to 10 Gbps, PoE++ of up to 90 W and uplinks of up to 40 Gbps) switches are complemented by the WAP841-IBE and WAP1241-IBE Wi-Fi 7 access points (5 and 10 Gbps uplinks), and everything is managed from SDLANet Manager.