Guidance on using Mimecast to whitelist Marketo IP Addresses

[Anonymous]

We use Mimecast and  would like to whitelist the Marketo IP addresses. However, by doing so leaves us entirely dependent on Marketo's gateway security with regard to spam that could originate from within that network. Also, if we are going to spoof our (sender) address as company's IP address, then we are going to run up against the Inbound Lockout protection which guards against spoofed spam.

We would want to know what sender address will be used, as well as which IP's will be used?

Please help.
 

[Rafael_Santoni1]

Gaurav,

Why not contact Marketo and get a fixed IP address for your Marketo instance/account? It probably has a cost, but that way only emails originated from your account will be using the IP address. If you do that, you can warm up the IP for bulk mailing, and also have visibility on your deliverability if you use Return Path or similar services.

Good luck!

Rafael