It is also a DAC high-speed cable. Just because 1 meter can be used does not mean that 5 meters can be used. This article disassembles the lengths according to the speed, looks at the length gears, attenuation sources and treatment methods after crossing the boundary, and provides an estimable path for the length in the cabinet.

First remember the regular gears of each speed

The common DAC lengths in commercial computer rooms are generally available in four grades: 1 m, 2 m, 3 m and 5 m. The higher the speed, the shorter the grade that can work stably: 5 m is common for 10G copper cables, 3 m is usually used as the boundary for 25G, and 100G uses100G DAC high speed cableMost of them are only placed within 3 m, and the specific length is still subject to the manufacturer's nominal length table.

Attenuation comes from wire diameter, frequency and connectors

Copper cables transmit electrical signals. The higher the frequency, the more obvious the skin effect. Insertion loss increases with frequency and length. The return loss and impedance mutation at the joint will reduce the eye diagram on the high-speed channel. Wire diameter is thicker10G DAC high speed cableThere is sufficient margin within 2 m, and the same length may be close to the threshold when placed on a 100G channel; this is why it is not recommended to directly transfer the cabling experience of the 10G era to 25G/100G.

There are two roads after crossing the border

  • Reduce the length of cabinets in the same cabinet or adjacent cabinets first: routing cables around a long distance will eat up one meter of margin. Shortening the path is cheaper than changing specifications.
  • When more than 5 m is required and low bit error is required, switch to an active optical cable carried by optical fiber, such as25G AOC active optical cable, common stalls can cover 7 m to 20 m.
  • For cross-column wiring or if the routing needs to be changed later, it is more flexible to use optical modules and LC jumpers, at the cost of one more cleaning and the power consumption of two modules.

Take the length according to the actual measured path and add a 0.5 m margin. Do not use straight-line distance to estimate. EB-LINK technical support can help you determine whether it falls within the safe range by comparing it with the port table. Call 0755-83179002.