Breaking bottlenecks in WLAN

In most cases, that infrastructure is dominated by 1-Gigabit per second copper cables that transport access point signals back to Ethernet switches. But connectivity demands and next-wave technology standards require greater bandwidth than 1Gbps.

Increasing the ability of the existing infrastructure to accommodate higher transmission rates promises to alleviate this infrastructure bottleneck and accommodate the growth in enterprise wireless connectivity in the most cost-effective, least disruptive way.

Enterprise local-area-network (LAN) technology deployed in most offices and campuses around the world has remained static at 1-Gbps transmission speeds for more than a decade. The broad proliferation of mobile devices generating traffic through these networks demands capacity well beyond this rate.

Figure: Copper cables in the walls and drop ceilings of enterprise campus buildings represent the current status quo of access network infrastructure and support 1-Gigabit per second data rates. However, a variety of next wave technologies, such as 802.11ac access points, demand greater bandwidth.

802.11ac Wi-Fi access points (APs), and Wave 2 in particular, demand Ethernet backhaul bandwidth of up to 6.9Gbps on the wired infrastructure side, but the copper cables that connect these WiFi APs to enterprise switches have reached their design limits. The vast majority of these UTP cable connections are either Category 5e or Category 6. Replacing these cables with higher speed 10Gbps links of Category 6a or above is costly, labor intensive, disruptive, and requires a monumental effort to upgrade billions of installed connections. Upgrading to fiber optic connections would be even more expensive and intrusive. Theoretically, enterprise and campus network administrators could upgrade these connections to 10Gbps or higher as soon as possible. In reality, the prevailing attitude is to leave the legacy cable infrastructure in place for as long as possible because it is still functional and reliable and the cost of replacing it is prohibitive.

By employing unique mixed mode signal processing in the physical layer ICs of these network connections, support for speeds up to 2.5Gbps and 5Gbps can be established on the majority of existing cables deployed in the enterprise. This upgrade will enable both 802.11ac WiFi APs and enterprise switches to meet the demand for greater capacity and higher volumes of traffic in enterprise access networks, allowing service providers to deliver a higher quality of experience to users of mobile devices.

Upgrading the enterprise
The migration to faster wireless access network speeds is essential to help enterprise keep pace with growth in smart phones, tablets, bring your own device (BYOD) access, Internet-of-Things (IoT), improved quality of service, 4k HD video, security, surveillance, teleconferencing, and simultaneous support of multiple users (MU-MIMO). Adoption of these technologies and trends requires a corresponding upgrade of the wired network infrastructure.

Adoption of advanced wireless connectivity technologies, such as 802.11ac WiFi and small cells, increases network access speeds to more than 1 Gbps. New WiFi/WLAN access points are being deployed in high volumes to replace slower 802.11n technology and the first wave of 802.11ac technology. Second generation 802.11ac, in particular, provides nearly 20 times the bandwidth compared to 802.11n, aggregating total payload throughput of up to 5Gbps.

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