Akisemt IP needed

My host server’s connection to Akismet has been on and off for the last two weeks, mostly off ….. I get an error message from the plugin that my API Key cannot be validated (it’s worked in the past).

I run a few weblogs all with the same key, for the moment, some still have varying versions of WP and the Akisment Plug-in. But all experience this problem.

My host can’t help without knowing the precise IP number for Akismet. How do I figure that out?