It is well known that both 100G QSFP28 AOC optical cables and 100G QSFP28 DAC cables are capable of transmitting data. However, there are some differences between them. In this article, Walsun will detail the distinctions between 100G active optical cables (AOC) and 100G direct attach cables (DAC).

>>>Read More:What is the difference between AOC and DAC 

What is a 100G AOC Active Optical Cable?

A 100G AOC active optical cable refers to a communication cable that requires external power during the communication process to convert electrical signals into optical signals, or optical signals into electrical signals. The optical transceivers at both ends of the cable provide electro-optical conversion and optical transmission functions, with a transmission rate of up to 100Gb/s.

What is a 100G DAC High-Speed Cable?

A 100G high-speed cable uses silver-plated conductors and foam insulation cores, offering excellent attenuation and low latency performance to ensure accurate signal transmission. It can also improve transmission speed and serves as a short-distance connection solution instead of optical modules. DAC cables are much cheaper than similar optical modules and have gained widespread popularity in short-distance connection applications.

Structure of 100G AOC Active Optical Cables and DAC High-Speed Cables

In simple terms, an active optical cable consists of two optical transceivers and an optical cable jumper, with optical transceivers at both ends and different lengths of OM3 or OM4 multimode fibers.

High-speed cables, abbreviated as DAC, are connected to switches or servers at both ends to achieve short-distance transmission. High-speed cables can be divided into two categories: passive high-speed cables and active high-speed cables. Active high-speed cables simply have an additional driver chip compared to passive ones. The "optical modules" on high-speed cables are not true optical modules; they only transmit electrical signals. Therefore, high-speed cables are cheaper than other optical devices. Even when using the same port as an optical module interface, high-speed cables can effectively save costs and reduce power consumption, which is why people choose them. Walsun offers customized length services for active optical cables to meet diverse needs.

Classification of 100G AOC Active Optical Cables

100G AOC active optical cables are divided into two types: 100G QSFP28 AOC and 100G QSFP28 to 4X 25G SFP28 AOC. The former has optical modules on both ends, achieving one-to-one transmission, while the latter has a 100G QSFP28 interface on one end and four 25G SFP28 interfaces on the other, providing customers with 100G data transmission capabilities.

Classification of 100G DAC High-Speed Cables

100G high-speed cables are divided into two types: 100G QSFP28 DAC direct attach cables and 100GE QSFP28 to 25G SFP28 DAC direct attach cables. The former has optical modules on both ends, achieving one-to-one transmission, while the latter has a 100G QSFP28 interface on one end and four 25G SFP28 interfaces on the other, providing customers with 100G data transmission capabilities.

Note: Although the classifications of the two types are similar, the optical transceivers in active optical cables have built-in lasers, while the modules in high-speed cables do not.

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