Transferring files from one computer to another usually requires the installation of some kind of server. Samba (or a network share, in Windows speak) is the classic approach to doing this. You can also use SSH to move files from one computer to another quite easily. But if you don't want to install and set up a server, the only option is to use a USB stick since very few desktop environments integrate tools for easy data transfer.

As an alternative to this, there are a number of simply designed programs that transfer files and folders over the local network at the push of a button without requiring an Internet connection. And the system does not rely on background services or cloud servers such as commercial services like Dropbox or Google Drive for this. Once installed on the desired computers, the programs automatically find each other in the network. Sending data is then a matter of a few mouse clicks. I will look at the current crop of candidates for this task.

Warpinator

Warpinator [1] comes from Linux Mint's rich repertoire of standalone developments but can also be installed on other distributions. Linux Mint automatically integrates the program into its default installation. Arch Linux and Manjaro have the application in their regular package sources. On other systems, the easiest way to install Warpinator is as a Flatpak, but this involves numerous dependencies [2]. Optionally, the project's GitHub page describes how to install from the source code [3].

Started from the application menu, Warpinator comes up with what is initially quite a clear-cut window. As soon as you launch the program on other computers in the local network, it lists these computers with the associated user and computer names (Figure 1). Click on one of the entries to open the detailed view. Use the asterisk next to the IP address in the header of the window to mark the corresponding computer as a favorite. This means that the entry will always appear in the upper area of the Warpinator instances activated on the network.

Figure 1: Warpinator automatically lists all active instances of the program on the local network in the application window.

To send a file, click on the desired target and select the desired file in the Send | Browse … dialog. Optionally, select an entire folder and then click the Add button below the file dialog. Warpinator will then transfer the directory along with all the files it contains. An even faster way is to simply drag the desired files into the File Transfers window.

On the target side, the user sees a message about incoming files. Clicking Accept starts the transfer, and the Reject button cancels the action. In the default configuration, Warpinator saves the transferred data to the ~/Warpinator/ folder in the current user's home directory (Figure 2). The folder can be customized in the application's settings. This is also where you define how Warpinator will handle existing files and configure the ports on which the application communicates on the network.

Figure 2: The history maintained by Warpinator for each client provides information about the status of each file and folder transfer.

Teleport

Teleport [4] minimizes what is already a very reduced structure in Warpinator to the bare essentials – a compact application window, a simple list of currently active devices, and a Send File button to start the file transfer (Figure 3). There are no further settings, and don't look for file manager integration or, say, the ability to transfer entire folders. The minimal range of functions is not surprising once you understand that the program originates from the Gnome cosmos, where the developers have been trying to reduce applications to the bare essentials for quite some time.

Figure 3: Teleport reduces Warpinator's approach to the bare essentials. Currently the program only lets you transfer single files.

If you like this extremely minimalist approach, the easiest way to install Teleport is to use a Flatpak [5]. Regular packages do not exist due to the still very young stage of the application's development. Not even the Arch User Repository (AUR), which is otherwise an almost inexhaustible source for installing the latest software, has a recipe for installation. Optionally, the developers describe on the project page how to compile the source code on Arch Linux and Ubuntu. Variants for other operating systems, as well as further functions such as encrypted data transfer or sending multiple files and folders, are on the developers' roadmap.

LAN Share

LAN Share [6], another open source app, follows a similar approach to that used by Warpinator. In a direct comparison, the biggest visual difference is the toolkit. While Warpinator is based on GTK and thus integrates perfectly with the Gnome or Xfce desktop, LAN Share uses the Qt toolkit. The application thus makes the best possible use of the KDE Plasma desktop's feature set. And this makes LAN Share easier to port to Windows.

Although the first release of LAN Share was almost five years ago, no distributions have integrated packages for LAN Share into their package sources thus far. On Arch Linux and derivatives such as Manjaro, there is the option of conveniently installing the program from the AUR. The developers offer deb packages [7] for users of Ubuntu and Debian. In addition, the project provides AppImages that work on all popular distributions [8].

For Windows, there is a setup with a standalone installation routine. In the test on a system with Windows 10, however, the program failed to launch because of a missing DLL file (MSVCR120.dll). However, installing the Visual C++ Redistributable Packages for Visual Studio 2013 [9] solved this problem without too much overhead.

To send a file, you need to install and start the program on all participating computers. Unlike Warpinator, LAN Share does not immediately list all the detected computers in the application window (Figure 4). The potential receivers do not appear until you click on one of the Send files… or Send folders… options and select an object to send (Figure 5). Once you select the target and press Send, LAN Share starts the transfer. If necessary, the transfer of larger volumes of data can be interrupted and resumed later on using the buttons top right in the application window.

Figure 4: The LAN Share main window lists the previous transfers but not the currently active clients on the network.

Figure 5: Users do not see the currently active targets for a data transfer until they initiate a data transfer.

By default, LAN Share writes the data to ~/LANShareDownloads/ in the current user's home directory. You can adjust the folder using the settings found in Settings | General, if so desired. The choice of options here is limited to the bare essentials. At this point, you cannot configure anything apart from the behavior when files with the same name are found and which network ports to use.