What is multi-gigabit?

Advances in wireless access points and Ethernet switch technologies are driving connectivity at the edge beyond one gigabit to multi-gigabit. In this series, we’ll discuss multi-gigabit technology and take a closer look at why organizations will ultimately require more than one-gigabit ethernet at the edge. We’ll also explore multi-gigabit standards and cabling, along with specific use cases, considerations and when multi-gigabit technology should be adopted. Lastly, we’ll conclude this series with a summary of Ruckus’ multi-gigabit portfolio.

The history of multi-gigabit

A decade ago, the predominant Ethernet switches moved to 1 GbE ports, superseding Fast Ethernet (100 Mbps), which was the previous prevailing standard. Today, most enterprise-class switches feature 1 GbE access ports. This is because 1 GbE is standard for almost all end-user devices, including desktops, printers, voice over IP (VoIP) phones and wireless access points (APs). For most users and devices, 1 GbE delivers adequate performance. For most applications, the connection to the switch is not the limiting factor to performance. Rather, a bottleneck is typically due to internet connection speed, or the response time of an application, application, user or device.

As the demand for Wi-Fi increases, so does the need for higher aggregate performance from the access points. More and more users, each with devices such as laptops, tablets, and phones, are using the latest Wi-Fi standards for higher performance. Concurrently, there is an increased dependence on wireless and cloud-based applications that lead to more total data being transferred via wireless access points. With prior generations of Wi-Fi, 802.11 (A, B, G & N) APs could only support up to about 600 megabits, though in real-world environments they couldn’t process more than 200 or 300 megabytes per second (throughput).

This means 1 GbE access ports were more than capable of handling all the data that earlier generations of APs could push out. 802.11ac (Wi-Fi 5) access points can hit up to 2.3 gigabits per second, though the practical limit is a little less. Most 802.11ac (Wi-Fi 5) APs are equipped with two 1 GbE ports, with some featuring 2.5 GbE ports. The next generation of 802.11ax (Wi-Fi 6) APs have begun shipping in the latter half of 2018. Theoretically, the PHYs will support almost up to 10 gigabits per second, although practical limits will ultimately mean somewhat slower throughput.

Conclusion

Today, most enterprise-class switches have one-gigabit access ports. As we noted earlier, this was sufficient to support 802.11n (Wi-Fi 4) since the total possible throughput via a wireless access point was below one gigabit per second. This means connecting to a switch with a one-gigabit port was adequate, as anything faster wouldn’t make any practical difference. This is because the AP was the limiting factor to performance. With the advent of 802.11ac (Wi-Fi 5) and now 802.11ax (Wi-Fi 6), an AP has the potential of more than one-gigabit throughput. Therefore, a 1 GbE access port could now possibly be the bottleneck to performance for Wi-Fi users. This is why there is an interest in connections higher than one gigabit per second between access points and switches.

Rick Freedman
Rick Freedman

Director, ICX Product Marketing

No Comments Yet

Leave a Reply