This is a Network Drive icon. We've made it in iOS style, first introduced in iOS version 7 and supported in all later releases up until now (at least iOS 11). This style is based on thin two-pixel lines and is optimized for 50x50 px. Unlike other vector icon packs that have merely hundreds of icons, this icon pack contains 12,500 icons, all in the same style and quality.
It's a logo of Network Drive reduced to an image of a cloud overhead of a drive. It is a drive that can be used to store information over the internet instead of on a hard drive. It looks like the network drive logo on my computer.