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Is 2.5G and 5G BASE-T just another speed? Let’s explore the trends behind these new speeds in detail.
The future of 802.11ac Wi-Fi will expand into second tier or Wave 2 of products as greater wireless range and performance is expected to extend into the enterprise. With Wave 2 802.11ac wireless access points aggregating up to 5 Gbps of throughput, the wired enterprise and service provider infrastructure is now being called on to connect these new access points to the network switches. The rapid growth of ever-more powerful desktop PC’s and mobile devices is continuously driving up demand for bandwidth and performance. As a result, the current capacity of installed hardware will soon be outpaced in these environments.
It is becoming evident that the backbone of wireless access networks—1 gigabit per second Ethernet—can’t be sustained and an infrastructure upgrade will soon be needed. The companies pushing up against the limits of 1 Gbps Ethernet already recognize this.
While 1000BASE-T Ethernet is limited in bandwidth, 10G BASE-T Ethernet requires UTP Cat6a cabling, a costly upgrade to the installed base of Cat 5e and Cat 6 that constitutes the majority today. Based on the information presented at the IEEE 802.3 NGEABT Study Group in Atlanta, GA in 2015, looking at the current cable install base, Enterprise access links (i.e., horizontal links) are dominated by 1000BASE‐T over Cat 5e/Cat 6. In a survey, where participants were asked to identify all major cable types in their horizontal links, Cat5e represented approximately 46% of installs followed by Cat6 at 28%.¹
This presents a compelling case for the introduction of products supporting both 2.5G and 5G speeds. These new BASE-T speeds have plenty of attributes to ensure success, such as ease of use, backward compatibility, faster speeds without requiring a cable upgrade, incremental speed upgrades, multi-vendor interoperability, not to mention optimized cost and performance.
In the last couple of years, two new alliances were founded to focus on building the ecosystem and consensus required to enable a new 2.5GBASE-T/5GBASE-T Ethernet standard. The NBASE-T Alliance supports the use of Aquantia PHY, while the MGBASE-T Alliance supports Broadcom PHY. The technology is based on data throughput over twisted pair copper cabling, up to 100 meters in length, over Cat 5e and Cat 6 cabling. Both alliances have released supporting 5-speed physical layer ICs (PHYs) 10G/5G/2.5G/1G/100M to address this market. The technology gives customers the ability to use higher data rates without having to replace existing infrastructure wiring. These new PHY’s come with the added bonus of supporting 10G BASE-T which still offers maximum performance up to about 55-60m over Cat 5e and Cat 6, depending on alien noise present over existing cabling. The IEEE 802.3bz Task Force has also adopted this technology and is targeting to ratify the 2.5GBASE-T/5GBASE-T Ethernet standard by the end of 2016.
The demand for 2.5G and 5G BASE-T products is clear. While re-wiring an entire building is both time-consuming and costly, these products will help optimize existing structural cabling, allowing enterprises and SPs to reap the benefits of higher performance. The cost savings associated with running on already installed cabling is substantial, estimated to be billions of dollars globally. With Ethernet’s continued expansion, there is a considerable demand for a flexible, cost-effective solution that these new speeds between Gigabit and 10 Gigabit will offer. To meet this demand, Spirent recently launched the world’s first 2.5 and 5G BASE-T Ethernet test solution.
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¹Cabling Installation & Maintenance Magazine, Cabling Market Outlook Consumption Trends and Analysis Enterprise and Data Center Organizations, February 2014
