Infrastructure
Shared IP
An IP address used by multiple senders, where reputation is influenced by all users' behavior.
Definition
A shared IP address is used by multiple email senders, typically customers of the same email service provider. Your reputation on a shared IP is influenced by all senders using it - one bad actor can affect everyone. Shared IPs are common for low-volume senders who don't send enough to maintain a dedicated IP's reputation.
Pro Tip
If using shared IPs, choose a reputable ESP that actively monitors and removes bad senders from shared pools.