Where can I find details of what the role of MCP is in Isilon

Been through the web administrator guide, security guide and cli guide and cannot find any sort of explanation for what this does. Have also gone through the VILT student notes and still see no reference however is it referenced and question are asked about it in the online assessments for Isilon diagnostic and trouble shooting assessment  as well in other Isilon tests

Is there a better reference or can somebody explain this feature