How Remote File Access Works

To understand how remote file access works, let's run through a typical experience.

Your service will install a file folder on your computer or device. Any file you drag or copy into that folder is duplicated -- using a secure sockets layer (SSL) and, in some cases, encryption -- onto a server somewhere on the Internet, much in the same way shared documents are stored on an office network. Meanwhile, a background service on your computer or device periodically syncs each of the folder's contents with its duplicate on the Internet server. Thus, any changes you make on one version of the file will be reflected in all versions.

Although once distinct concepts, the line separating "remote file access" from "cloud computing" grows increasingly blurred, both in terms of the services they provide and the way companies market them. We use the term remote file access throughout this article, but the services we describe overlap the two categories somewhat.

Most services allow you to access your remote file folder from devices such as tablets and smartphones. Simply install the necessary app and you're ready to go. In many cases, an additional option to share your photos, videos or other files on the remote file service then appears on your app menus. For example, a Google Drive user with an Android phone who takes a picture will see a Google Drive option on the sharing menu, next to Picasa, Twitter, Facebook and so on. Like your desktop computer, these devices will sync every so often with the file servers, much as they periodically check for new e-mails or texts.

Once your files are on a remote access server, you can share them publicly or with specific people. Implementations vary, but typically a settings menu lets you specify who can see a particular document, which can vary from anyone on the Web, to anyone who has the link, to only specified people. Many services require users to register and make an account (typically free) before they can access the file. You can also specify permissions controlling what viewers or collaborators are allowed to do with the file (like read only, edit).

Some services, like Google Drive and Microsoft SkyDrive, also enable you to create documents online. These are stored on the server, but you can also download them to your computer or device to work on them while offline. The system will sync them with the remote file service once you re-establish Web access.

Remote file access and cloud servers provide powerful tools and convenient file access, but they also introduce security vulnerabilities. These cut two ways: On the one hand, hackers can and will exploit security holes in the servers and on devices that access them; on the other, many users will rankle at security solutions proposed to stop those hackers, particularly digital rights management (DRM). Keep such concerns in mind when choosing a remote file access service -- or deciding if one is right for you in the first place [source: Thomas].

The Web is full of one-stop solutions where you can drop your files and let someone else sweat the details, with more coming online all the time. Here are a few of the standouts.

Dropbox is a straightforward service with a long track record. It works on Windows, Mac and Linux operating systems and offers apps that tie into iPhones, iPads, Androids, BlackBerrys and Kindle Fires. Customers begin with 2 gigabytes of storage and can accrue more via customer referrals or purchase up to 500 GB by going pro. A business variant with version control and some team management and collaboration options starts at 1,000 GB (no expansion limit) [sources: Dropbox; Meece].

iCloud offers the inevitable "one nation under Apple" solution for the company's core customers, but PCs running Windows Vista or later can get in on the action too. If your Apple device is fairly new (and if not, what's the matter with you?), then a wizard is probably walking you through the process even as you try to read this article. In addition to providing access to content on all of your devices (particularly iTunes and App Store purchases), iCloud keeps track of where you left off in your iBook or Safari browsing, and can even lock down and help track a stolen device. Users begin with a free 5 GB, but can purchase more space (up to 50 GB as of October 2011). Music, TV shows, apps and books bought through the Apple Store do not count against this limit, but storing non-iTunes music costs extra [sources: Apple; Meece].

Google Drive aims to set users free from any platform entanglements while simultaneously drawing you -- and your data -- deeper into the Googleverse. It works on Windows (Vista or later), Macs (Snow Leopard (10.6) or later) and Android devices (Eclair (2.1) or later), as well as iPhone and iPad (iOS 3.0+) and offers 15 GB free with pay plans expandable to 16 terabytes (that's right – we said terabytes). Like Microsoft's Skydrive (below), Google Drive allows users to create spreadsheets, docs and presentations online, and supports file sharing and collaboration with 30-days' worth of revision tracking. What really sets it apart, though, is access to Google's powerful search capabilities [sources: Google; Meece].

Microsoft SkyDrive leverages its strongest assets as well: namely, the ability to collaborate, with version control, on Word docs, Excel spreadsheets and PowerPoint presentations without converting them to an open source or other file format. The service also grants you access to remote computers running Windows, so you can grab photos or stream video from your home computer to your device. Microsoft starts you off with 7 GB free, with options to upgrade to 200 GB [sources: Meece; Microsoft].

Those are just a few of the many options available to you. Take your time and search out the solution that fits your particular needs.