Еvery inbox provider is monitoring the IP address of incoming traffic and tracks a reputation score for those IPs. Having a dedicated IP means that you are the only one responsible for its reputation. This is important because one of the major factors in determining what emails land in the inbox, without being blocked or filtered, is the reputation of the IP address sending it. The minimal required volume from most of the ISPs is 150,000 emails per month, and 5,000 emails per day. This is because lower volume senders will not be sending frequently enough for ISPs to consider your dedicated IP to have a good reputation.In contrast, a shared IP address is one that is pooled among many different senders. This means the email behavior of one sender can affect others. Shared IPs are sometimes necessary because not every sender has enough email volume to support a dedicated IP.