Marvell Essential Technology Blog
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The flexibility offered by wireless networking is revolutionizing the enterprise space. High-speed Wi-Fi®, provided by standards such as IEEE 802.11ac and 802.11ax, makes it possible to deliver next-generation services and applications to users in the office, no matter where they are working.
However, the higher wireless speeds involved are putting pressure on the cabling infrastructure that supports the Wi-Fi access points around an office environment. The 1 Gbit/s Ethernet was more than adequate for older wireless standards and applications. Now, with greater reliance on the new generation of Wi-Fi access points and their higher uplink rate speeds, the older infrastructure is starting to show strain. At the same time, in the server room itself, demand for high-speed storage and faster virtualized servers is placing pressure on the performance levels offered by the core Ethernet cabling that connects these systems together and to the wider enterprise infrastructure.
One option is to upgrade to a 10 Gbit/s Ethernet infrastructure. But this is a migration that can be prohibitively expensive. The Cat 5e cabling that exists in many office and industrial environments is not designed to cope with such elevated speeds. To make use of 10 Gbit/s equipment, that old cabling needs to come out and be replaced by a new copper infrastructure based on Cat 6a standards. Cat 6a cabling can support 10 Gbit/s Ethernet at the full range of 100 meters, and you would be lucky to run 10 Gbit/s at half that distance over a Cat 5e cable.
In contrast to data-center environments that are designed to cope easily with both server and networking infrastructure upgrades, enterprise cabling lying in ducts, in ceilings and below floors is hard to reach and swap out. This is especially true if you want to keep the business running while the switchover takes place.
Help is at hand with the emergence of the IEEE 802.3bz™ and NBASE-T® set of standards and the transceiver technology that goes with them. 802.3bz and NBASE-T make it possible to transmit at speeds of 2.5 Gbit/s or 5 Gbit/s across conventional Cat 5e or Cat 6 at distances up to the full 100 meters. The transceiver technology leverages advances in digital signal processing (DSP) to make these higher speeds possible without demanding a change in the cabling infrastructure.
The NBASE-T technology, a companion to the IEEE 802.3bz standard, incorporates novel features such as downshift, which responds dynamically to interference from other sources in the cable bundle. The result is lower speed. But the downshift technology has the advantage that it does not cut off communication unexpectedly, providing time to diagnose the problem interferer in the bundle and perhaps reroute it to sit alongside less sensitive cables that may carry lower-speed signals. This is where the new generation of high-density transceivers come in.
There are now transceivers coming onto the market that support data rates all the way from legacy 10 Mbit/s Ethernet up to the full 5 Gbit/s of 802.3bz/NBASE-T – and will auto-negotiate the most appropriate data rate with the downstream device. This makes it easy for enterprise users to upgrade the routers and switches that support their core network without demanding upgrades to all the client devices. Further features, such as Virtual Cable Tester® functionality, makes it easier to diagnose faults in the cabling infrastructure without resorting to the use of specialized network instrumentation.
Transceivers and PHYs designed for switches can now support eight 802.3bz/NBASE-T ports in one chip, thanks to the integration made possible by leading-edge processes. These transceivers are designed not only to be more cost-effective, they also consume far less power and PCB real estate than PHYs that were designed for 10 Gbit/s networks. This means they present a much more optimized solution with numerous benefits from a financial, thermal and a logistical perspective.
The result is a networking standard that meshes well with the needs of modern enterprise networks – and lets that network and the equipment evolve at its own pace.
