How to choose the Direct Attach Copper Cable correctly?

qsfp sfp DAC AOC

How to buy the Direct Attach Copper Cable ?

1.Choose the Right Connector

DAC cable terminated with SFP+ connectors is commonly used in 10GbE networks. However, there are many other connector options for DAC cables which meet the interconnection demands of higher speed networks. Thus, choosing the right connector according to your network requirement is very important. In general, you could choose the SFP+ for 10GbE, QSFP+ for 40GbE, SFP28 for 25GbE and QSFP28 for 100GbE. In addition, breakout DACs like QSFP+ to 4x SFP+ DAC is an ideal choice for 10G to 40G migration.

2. AWG Is Also an Important Factor

AWG is another important factor of DAC cables. General specifications like 24AWG, 28AWG and 30AWG are available in the market. Always remember a rule when choosing the AWG—the longer the distance, the higher the AWG rating should be.

3. Choose the Enough Length

The maximum cable length differs from passive and active DAC cables. Generally, passive cable supports 5 meters or shorter lengths. Whereas active cable can support more than 5 meters (up to 15 meters). Thus, when the distance between connection points is less than 5 meters, passive DAC cable is recommended to use but ensure that your switch can support the passive cable (refer to the first guide). When the distance exceeds 5 meters, it is highly recommended to use active DAC cables to ensure the signal is transferred all the way through. The cost may be a bit higher, but the signal is improved and gives peace of mind by creating a trustworthy connection.

Direct attach copper cables are a low-cost alternative to traditional fiber and twisted-pair copper cabling in top-of-rack and middle-of-row. When buying a DACs, parameters such as passive or active, cable connector, AWG, length and so on should be properly selected. This post is a simple buying guide for reference. If you want to purchase high-quality and cost-effective DAC cables, it is highly recommended to visit www.szrollball.com or contact sales@rollball.com.cn for more details.