Is it safe to include ip addresses in emails between network teams?

Just wondering if there was a better way for two teams to interact with each other over written communication without exposing ips.

Given that: * Both teams are in different companies * Both uses corporate emails * ips and network designs and discussions to link two networks are in being discussed.

When by mistake an outside recipient was added to the newest email containing the whole thread of ips and networks.

With cyber attacks on the rise; just being paranoid here. But then again even if ips and designs are to leak it is still our cyber security that will stop potential attackers.

Any ideas on how to avoid this and still get both teams to easily interact with each other?