Restricting the sending, and receiving, of email at Google Apps for Work to only possible within Zoho for selected accounts

Restricting the sending, and receiving, of email at Google Apps for Work to only possible within Zoho for selected accounts

Hi, does anyone know how I can prevent lazy and non compliant reps from sending or receiving emails outside of Zoho for the accounts in use there?

We use Google Apps for work and they have quite sophisticated routing features and the ability to restrict, but I have not been able to find a recipe or any reference to what information I might need, as in the address of the zoho mail servers, or the ip address or other unchanging identifier for the Zoho mail add on within Zoho CRM I would need to plug into Google Apps for Work.

any help welcome, thanks.

Jasper Lawrence