There are a wealth of methods that can be used to allow users to share files on a local network. As with so much else in computing the popular methods are all we need to concern ourselves with. The simple fact of the matter is that, as Windows is the dominant platform, chances are any computer, regardless of operating system, will have to interact with a Windows system on even the smallest network.

Windows operating systems use the Server Message Block, or SMB set of protocols. These operate over TCP, much like standard Internet traffic. It has been revised multiple times, even at one point being renamed to the Common Internet File System, CIFS. It is, as of Windows Vista, known as SMB 2.0 and includes support for most common files and things like shortcuts. It operates on the layer above TCP, giving users access to other computer’s shared folders through ‘My Network Places’ or similar locations within Window’s explorer. This keeps things simple, allowing users to remove the physical element involved with transferring files using a physical medium such as USB drives or, heaven forbid, a floppy disk, which could be lost or broken. Of course, this can still be the accepted method with other operating systems, for those without experience.

Much of the work done enabling cross-platform file sharing has been done by tireless individuals who reverse-engineer closed protocols. Lacking any documentation the only choice is to passively watch how a protocol does its thing. This painstaking process lead to the creation of Samba. Samba is a client-server application used by Unix systems to access Windows shares. It comes as standard on most Linux installs and is what allows Mac OS X Leopard to recognise Windows machines and label them with the now notorious CRT ‘Blue screen of death’ icon.

Of course non-Windows machines aren’t tied down to using Microsoft approved methods for their LAN transactions. Unix users can avail of NFS, the network file system designed by Sun Microsystems. The difference to users is minimal, with remote files and folders as easily browsible as local ones. Mac OS X even includes a working Apache setup as default, allowing any computer on the network to access it as a website by using its IP address in a Internet browser.