Salt Transport

One of fundamental features of Salt is remote execution. Salt has two basic "channels" for communicating with minions. Each channel requires a client (minion) and a server (master) implementation to work within Salt. These pairs of channels will work together to implement the specific message passing required by the channel interface.

Pub Channel

The pub channel, or publish channel, is how a master sends a job (payload) to a minion. This is a basic pub/sub paradigm, which has specific targeting semantics. All data which goes across the publish system should be encrypted such that only members of the Salt cluster can decrypt the publishes.

Req Channel

The req channel is how the minions send data to the master. This interface is primarily used for fetching files and returning job returns. The req channels have two basic interfaces when talking to the master. send is the basic method that guarantees the message is encrypted at least so that only minions attached to the same master can read it-- but no guarantee of minion-master confidentiality, wheras the crypted_transfer_decode_dictentry method does guarantee minion-master confidentiality.