CAT6a is a 10-Gigabit Ethernet (10-GbE) over copper proposal to the CAT6 standard. The IEEE published a draft standard (Std 802.3an) in October 2004. The draft calls for 10-Gigabit data transmission over a 4-connector twisted-pair copper cable for a distance of 100 meters on Class F or Class E-augmented copper cabling. Class E cabling requires a line-encoding scheme (PAM 12) and electronics to achieve the 10-Gbps transmission for 100 meters. Current CAT6 cabling systems may support 10-Gigabit Ethernet over limited distances.

The draft extends CAT6 electrical specifications from 250 MHz to 500 MHz. It also proposes a new measurement: Power-Sum Alien Crosstalk to 500 MHz. Alien Crosstalk (ANEXT) is a coupled signal in a disturbed pair arising from a signal in a neighboring cable.
To virtually eliminate the problem of ANEXT, CAT6a F/UTP cable can be used. The F indicates an outer foil shield. This cable is also a good choice when security is an issue because it doesn’t emit signals. In addition, CAT6a F/UTP cable works well in noisy environments with a lot of EMI. Installation is simpler, too, because the cable’s construction makes it easier to pull and more resilient. The cable also has a smaller diameter so you can run more cables in a conduit.

Blade servers are hot. Really hot. These slim, high-powered CPUs generate heat like nothing you’ve ever installed in your data center before—a rack of blade servers can generate more heat than an electric oven! And as temperatures rise, servers may fail, leading to downtime and even data loss.

Needless to say, blade servers present a cooling challenge. If you plan to install them, you need to make sure you can accommodate their cooling needs.

Computer rooms have special equipment such as raised-floor cooling systems to meet their high cooling requirements, but it’s also important to ensure that cabinets used to house blade servers provide adequate ventilation—even in a cool room, hot spots can develop inside cabinets if air distribution is inadequate.

If you’re planning to install blade servers or other high-density components in cabinets, look for a cabinet with fully perforated doors in the front and rear— the greater the amount of perforation, the more cool air can be delivered to the components.

Don’t overload the cabinet by trying to fit in too many servers—75% to 80% of capacity is about right. Leave at least 1U of space between rows of servers for front-to-back ventilation. And finally, ensure all unused rack space is closed off with blank panels to prevent recirculation of warm air back to the front of the cabinet.

If you need help calculating your system’s cooling needs, contact our FREE Tech Support.