Wireless: 802.11ac May Break Your Wired Network
July 18, 2012 Leave a comment
- 802.11n, which capped out at a max of roughly 500 Mbps in ideal cases, never filled the 1 Gbps link with which many were connected, avoiding bottlenecks at the access port itself (though potentially congesting aggregation links).
- 802.11ac, with its initial specification release capably supporting 1.3 Gbps throughput on a single AP, may force a ‘re-think’ on access point attachment and how traffic will be routed onto the physical infrastructure and ultimately back to the data center or services location.
Wireless enterprise networks are a must today for both efficiency and convenience. More frankly, they are necessary to be competitive. The market gets this, as indicated by the continued healthy growth of WLAN as a segment. Originally, 100 Mbps links often connected 802.11a/b/g APs, and given that the top throughput was often less than the 54 Mbps throughput of 802.11g, no bottlenecks were encountered. Then came 802.11n; in many cases, it was either proceeded by or coupled with a Gigabit network upgrade, sufficient to support the initial 150/300 Mbps and scaling to 600 Mbps (in a perfect world), as well as multiple radio technologies. This is still well below the 1 Gbps links that in some cases supply connectivity and power (PoE) to the 802.11n access points. However, with the next-generation 802.11ac specification nearing completion and its initial release throughput providing up to 1.3 Gbps connectivity, we reach the first throughput bottleneck from the AP to the wired environment. No debate has come up yet in the public forums regarding how one would wire and architect an 11ac network, but it is certain to become an issue in the coming quarters as commercial products become available. There is no specification for 10Gbase-T PoE currently, few (if any) access points in the past have had multiple Ethernet ports to connect to the network, and the current link technology employed (1GbE) will be oversubscribed.
This seems to me like an opportunity for someone to create a multi-link AP. True, using wireless backhaul will enable APs to route between themselves at the optimal 1.3 Gbps, in addition to few networks even seeing 1.3 Gbps traffic patterns initially. However, good network design practices (as well as the explosion of wireless traffic demands) dictate that enterprise IT designs the next WLAN based on 802.11ac to be built as robustly as possible. I would welcome your thoughts on this issue, including how significant it may be (whether initially or longer term) and how you intend to address this in your own environment.