1.8.5 OpenVPN

TME networking capabilities are expanded using the OpenVPN tools. These come included with TME to provide alternate methods for network access, besides the built-in BPF and TAP. One advantage of using these is that, in some cases, they allow for greater portability to platforms that don’t have native BPF or TAP. Another pro is that OpenVPN provides value-added capabilities such as encryption, fragmentation, compression, virtual networking, and scripting. These can be used to greatly expand the domain of application to larger systems. There is an ongoing effort to bring in more of this functionality over time.

To begin with, some OpenVPN capability has been imported using modules that map to certain elements in the OpenVPN program. In particular, TUN/TAP devices and link sockets are two new TME elements that can be used to network machines and hosts. The elements can be thought of as subsets of OpenVPN itself, with the capabilities specified using the same command-line options that it provides. Some will work and some won’t, depending on what has been implemented, and what is needed for that element.

The following sections outline these methods.