Jozabad is a broker and client library of a custom hub-and-spoke communication protocol. Workers connect to a broker and send messages to the broker. The broker joins pairs of workers together in channels and forwards messages between connected workers.
Jozabad is thus, basically, like a telephone exchange. It is inspired by the ITU's X.25 protocol.
The basic goals of the protocol are these:
The broker ensures that
- messages are valid
- data rates are obeyed
A worker can
- connect / disconnect to the broker at will
- get a list of other available workers from the broker.
- request a channel with any other idle worker
- is exclusive -- a worker can have only one channel at a time
- is persistent -- it exists as long as the workers want
- is stateful
- is pseudonymous -- the workers only know one-anothers' pseudonym, and not their IP address
The future goals of the protocol are these:
- The protocol will use future ZeroMQ security protocols to authenticate workers and encrypt traffic.
The name "Jozabad" refers to a talented archer that fought with the biblical King David. The image the archer is a metaphor for hub-to-node information transmission.
Jozabad is the lowest level of a three layer application stack.
- Jozabad handles low-level communication.
- Johanan is a packet assembler and disassembler, expressing a stream-like interface (fprintf, fgetc) for intra-worker communcation based on Jozabad messaging.
- Jahaziel is a text protocol with in-band escapes for colors, graphics, and audio, and a rendering engine for that protocol.
The documentation, such as it is https://github.com/spk121/jozabad/blob/master/doc/jozabad.pdf?raw=true
- Jozabad is inspired by the ITU's X.25 protocol: specifically its message types and state machine. It is not a true implementation of X.25 over TCP, which is known as XOT.
- It uses ZeroMQ sockets to do all the heavy lifting.