PJON is based on a concept of selectable "strategies" to support using the protocol with different physical media. Some of these, like the one named SoftwareBitBang which allows a bus on a wire connected directly to an I/O pin, are very compact.

There are also strategies for TCP and UDP based communication, essentially using the same packet structure but sending them as TCP or UDP over a LAN or WAN. These strategies need the Ethernet library, and use more memory.

Still, the memory requirement is small enough to run a router with two PJON objects with the strategies SoftwareBitBang and DualUDP on an Arduino Nano with a W5500 Ethernet shield. This allows easy traversal between different physical media, and IP-based communication, also with PJON-based software running on a Windows or Linux computer.