For most enterprise networks, ongoing architecture evolutions to the WAN, the data center, and public and private clouds have been commonplace over the past decade. Yet, within the campus LAN, things have remained relatively the same. That status quo is about to change, however, as technologies like Wi-Fi 6 and IoT threaten to debilitate legacy campus networks from a throughput perspective. Let's dig into why and what can be done about it.
Wired Ethernet access to a desktop has remained relatively stagnant over the years. Instead, most technological and speed advancements have happened on the wireless side. The BYOD movement within enterprises caused the first major uptick in wireless device usage.
Fortunately, the Wi-Fi limitations of 802.11n and 802.11ac Wave 1 technologies inadvertently helped curtail usage in terms of connected Wi-Fi device density and overall throughput consumption. Thus, because of the technological deficiencies inherent in enterprise Wi-Fi at that time, access switches and uplinks into the distribution layer were largely able to handle the added bandwidth brought about by the BYOD movement.
As Wi-Fi access points (APs) upgrade to 802.11ac Wave 2 and the latest Wi-Fi 6 technologies, those technological limitations will be a thing of the past. That means more devices can be connected and each device can send and receive more data than ever before. It also means campus LAN switches are poised to create bottlenecks in two potential areas: between the access switch and the wireless AP and between the access layer and campus LAN layers.
Let's look at these potential bottlenecks using Wi-Fi 6 as an example.
Access switches and wireless APs
Wi-Fi 6 APs have a theoretical throughput capacity of up to 10 Gbps. That's nearly 40% more than 802.11ac Wave 2 and several times faster than 802.11n. Additionally, the Wi-Fi 6 specification delivers advancements for several underlying technologies designed for more efficient connectivity and bandwidth sharing. This translates into more devices being able to connect to a single AP.
Because more devices can be reliably connected, enterprises can deploy a slew of IoT devices. These devices can include temperature monitors, intelligent lighting, or even advanced 4K and 8K surveillance cameras.
The bandwidth these sensors consume can vary widely depending on their need -- a common range is between a few Kbps to hundreds of Mbps. For large IoT deployments, even sensors that consume only a small amount of bandwidth can add up quickly once hundreds or thousands of IoT devices connect and start communicating.
From a wireless perspective, this means you can no longer connect a Wi-Fi AP using a 1 Gbps Ethernet link, as is commonly done in most legacy access layer networks. Doing this would limit the benefits Wi-Fi 6 can deliver.
Instead, the ideal option is to upgrade to switches that use multigigabit Ethernet technologies driven by the NBASE-T and Ethernet Alliance global consortium. Upgrading switches to multigigabit ports can enable an admin to connect multigigabit-capable wireless APs or other devices to switches without creating a bottleneck. The result is Ethernet speeds that range between 2.5 and 5 Gbps on a single connection with existing CAT5e or CAT6 copper cabling -- or up to 10 Gbps with CAT6A or newer cabling.
The access layer and the campus LAN
A second potential network bottleneck is the uplink between the access layer and the campus LAN layers. In many cases, the uplink may be a 1 Gbps link or several aggregated 1 Gbps links. Yet, even with aggregated links, connectivity between access and distribution switches may not be enough for data-hungry Wi-Fi and IoT devices. Thus, migrating to newer 10 Gbps uplinks -- and even 25 and 40 Gbps uplinks -- might be in order.
Keep in mind that upgrading to faster uplink speeds may be more difficult than you expect. Not only do you need to upgrade to new switch hardware that supports faster transmission speeds, you also need to consider the type of cabling to install between access and distribution layer switches.
In general, a faster uplink speed means the network is more sensitive in terms of cable and fiber quality and distance limitations. Thus, an upgrade to 10 Gbps or higher speeds often equates to an upgrade of the physical cable plant. For larger networks, this can get expensive quickly.
Enterprises should perform due diligence to verify and budget for potential hardware, software and cabling upgrades to achieve the desired uplink speed results.