Thunderbolt (formerly known as “Light Peak”) is an external connection that allows 10 Gbps (around 1 GB/s) of data transfer in each direction. In this tutorial, we will explain everything you need to know about it.

The two main advantages of Thunderbolt are the use of the existing PCI Express and DisplayPort protocols and the use of an existing connector, the mini DisplayPort (mini DP). Because it uses existing protocols, it is not necessary to install an additional driver on your PC in order to use a Thunderbolt connection.

Figure 1: The Thunderbolt architecture

Thunderbolt can carry either computer data, using the PCI Express protocol, or digital video, using the DisplayPort protocol. This means that the other end of the cable can be attached to either an external storage device such as a DAS (Direct Attached Storage) box featuring a Thunderbolt port or to a video monitor with a Thunderbolt port. Since the cable can carry both video and data, the video monitor must have a Thunderbolt chip in order to capture the video data; regular monitors using a DisplayPort or a mini DisplayPort connector won’t work directly with Thunderbolt. It is possible that manufacturers will release an external box with a Thunderbolt controller in order to allow a Thunderbolt connection on regular video monitors.

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Figure 2: How Thunderbolt works