Managed service providers (MSPs) offer additional services on top of a vendor’s SaaS product in exchange for a recurring fee. They are able to carve a revenue stream by providing customers with technical support for the product. Working with MSPs typically mean agreeing to longer term contracts because of that ongoing support (in comparison to working with value added resellers that provide more transactional work).
Also see: "value added resellers."
A measure of the partner-sourced revenue that's generated on a monthly basis.