ZeroMQ vs Crossroads I / O

Question

I consider using ZeroMQ as a messaging / transport layer for a fairly large distributed system, mainly for monitoring and data collection (many manufacturers, several consumers).

As far as I can see, there are currently two different implementations of the same concept; ZeroMQ and Crossroads I / O, the last of which is the ZeroMQ plug (in 2012?).

I am trying to figure out which one to use and wonder about the differences between them, but have not yet found much information about this.

For example:

• Are they compatible with wiring?
• Are they compatible with the API, i.e. some general basic API, possibly with various additions?
• Do they both support ZMTP (ZeroMQ messaging protocol)?
• Do they have some kind of common understanding of future development or will they continue in two different and possible different directions?
• What are the pros and cons in relation to the other?

Basically, how to choose one of them?

Answer 1

Crossroads.io is pretty dead since Martin Sustrik started work on a new stack in C called nano: https://github.com/250bpm/nanomsg

Crossroads.io does not use afaik, implements ZMTP / 1.0 and ZMTP / 2.0, but its own version of the protocol.

Nano has plug-in transports, and we are likely to make ZMTP transport for this. Nano is really nice, rethinking the original libzmq library, and if it manages to make a good new kernel.

Ideally, Nano will interact both at the API level and at the protocol level, so replace libzmq with a replacement. However, he has a pretty long way to go.

Note that several libzmq rewrites have now appeared, including JeroMQ (Java) and NetMQ (C #). The two really implement ZMTP / 1.0 and ZMTP / 2.0. There are also other libraries, such as Axon (https://github.com/visionmedia/axon), which are strongly inspired by 0MQ but are not compatible.

Based on experience, users rate interoperability more than almost anything else, so it is likely that different 0MQ-like stacks will speak the same protocols.