Unveiling the Evolution of Wireless Infrastructure
By CWNP On 11/28/2023
In 2007, the wireless world buzzed with excitement over the potential of 802.11n to transform infrastructure design. Today, we revisit those early predictions to analyze the developments in the landscape.
In 2007, the wireless world buzzed with excitement over the potential of 802.11n to transform infrastructure design. Today, we revisit those early predictions to analyze the developments in the landscape.
Power Over Ethernet (PoE) Evolution
Back in 2007, a significant concern revolved around the power consumption of 802.11n access points (APs) equipped with multiple radio chains. At that time, the prevailing PoE standard, 802.3af, provided a maximum of 12.95W, which fell short of most 802.11n APs. The good news is that within 6-9 months, 802.3at, also known as PoE+, was introduced, capable of delivering up to 25.5W. This advancement significantly eased the support for 802.11n APs, even those with multiple radio chains.
Some vendors incorporated dual-band 802.11n radios and Wireless Intrusion Prevention System (WIPS) functionality to enhance redundancy and reliability in a single enclosure. Furthermore, with the arrival of 802.3bt (PoE++), capable of delivering up to 100W of power, the power challenges for high-performance APs have largely been resolved.
Architectural Changes and WLAN Controllers
Discussions in the early days of 802.11n highlighted concerns about overwhelming WLAN controllers due to the high throughput capabilities of 802.11n. However, the adoption and deployment of 802.11n did not immediately lead to controller overload. 802.11a/g networks continued to be sufficient for many deployments for several years. The need to upgrade Ethernet infrastructure to gigabit, as initially considered, proved unnecessary, as a 10/100 Ethernet infrastructure continued to be suitable for supporting 802.11n, a fact that remains true today.
Today, the principal challenges have shifted towards RF planning and protection mechanisms, especially in high-density environments. Additionally, with the proliferation of handheld client devices, such as scanners and phones, which may not support the 802.11n PHY for some time, the focus has shifted towards optimizing network performance and security.
Distributed Data Forwarding (DDF) Architecture
Previous discussions introduced the concept of distributed data forwarding (DDF) or hybrid architectures. In this model, the data plane is moved back to the AP to enable direct data frame transmission, a concept that has gained prominence in recent years.
One approach to address Layer 3 (L3) roaming in a DDF architecture is to tunnel the data plane back to the WLAN controller exclusively for L3 roamers, allowing data to be sent directly to its destination at other times. This approach effectively mitigates issues such as VLAN tagging at the edge.
Another noteworthy development involves the incorporation of application-layer intelligence and configuration options in both the controller and AP. This enables fine-tuned control over switching frames directly to their destination (DDF) or tunneling them back to the central controller (centralized). Such flexibility caters to the diverse demands of enterprise applications, encompassing high-security and time-sensitive requirements.
In the DDF architecture, distributed encryption and decryption have become essential to optimize over-the-air bandwidth. This is particularly valuable in mesh environments, where conserving and efficiently using bandwidth resources is paramount.
The wireless landscape has seen remarkable progress since 2007. Improvements in PoE standards, the continued viability of 10/100 Ethernet infrastructure, and the evolution of architectural choices have all adapted to the escalating demands of wireless networks. The journey of 802.11n from its inception to 2023 has indeed been transformative.
Tagged with: cwnp, wireless, wireless design, network design, poe, power over ethernet, wlan, ddf
Blog Disclaimer: The opinions expressed within these blog posts are solely the author’s and do not reflect the opinions and beliefs of the Certitrek, CWNP or its affiliates.