Enterprise provides its clients with Shared IP Space (a pool of established sending IPs) and optional Dedicated IPs (DIPS) from which messages can be sent. Both Shared IP Space and DIPS are part of iPost’s FBL loop, which includes all major domains, so that subscriber complaints are received in real-time and the subscriber’s email address is immediately unsubscribed. Both metrics are available in various client reports, including the Email Summary Report. An example is shown below:

You are advised to closely monitor your campaigns for elevated levels of complaints and/or unsubscribing activity after each Send, and particularly during the IP Warm-up period, which usually takes 6-10 weeks, depending on send volumes and frequency. If these two-metrics spike, it is an indication of a problem which should be investigated and remediated right away. Doing so will help prevent delivery problems such as spam listings or messages routing to the spam folder or junk box.

During the IP Warm-up period, you are in effect establishing a sender reputation with major ISPs (Internet Service Providers), such as AOL, Gmail, Hotmail, Yahoo and many others. Smaller domains used by subscribers and reporting services such as Barracuda Networks, SORBS and others are also important. It is critical, just like in life, to make a good first impression!  We recommend that you initially send emails to only highly engaged subscribers, e.g. 30-day openers, clickers, purchasers, and new sign-ups. Then you can gradually add slightly less engaged ones, e.g. 60-day, and then 90-day, etc. However, every organization is different and the most suitable approach may vary. Be sure to consult with your Customer Success Manager about an appropriate ramp-up schedule.

For clients with optional DIPs, initially 90% of message traffic will be sent from the Shared IP Space and 10% from the DIPs. The percentages sent from the DIPs will then gradually increase during the warm-up period until they are close to 100% seasoned. Note that a small percentage of “< 5%” of message traffic may continue to be sent through iPost's other IPs which handle deferral sending.

After the IP period is complete or during its last phases, you can begin to blend in non-engaged subscribers. This needs to be done both thoughtfully and carefully. If folks are not engaging with your messages it is a sign! What are they telling you?  We recommend A/B testing the subject line, preheader and message body to optimize your message to non-engaged subscribers and get them back on board again!

Each ISP will have its own definition of engagement and thresholds for negative metrics, such as complaints and unsubscribes. Roughly speaking, we recommend aiming for a modest 10% Open rate and/or 1% Click-through rate to maintain inbox placement. iPost provides detailed domain statistics that allow you to quickly determine if you are achieving this goal. 

If you have any questions about overall Delivery or about the IP Warm-up process, please contact iPost Client Services.