Deliverability Reporting: Gateway to Dividends | Port25 Solutions, Inc.
Case Studies
Fred Tabsharani

By port25admin

Deliverability Reporting: Gateway to Dividends

When purchasing sophisticated email delivery software, it’s often challenging to determine whether the intrinsic value of the full feature set is worth the cost of the product.  Software value can be challenging to measure because it is difficult to quantify the value of deliverability related functionality. To address this issue, most commercial grade MTAs offer an extensive set of “deliverability reports” to determine if their sends are being delivered efficiently, and subsequently, if the software is having a positive impact on business.

When dealing with various types of sending infrastructure, many questions arise about what happens to the mails injected into the system. Were they delivered to the inbox? How rapidly were they deployed? Which email sources/domains performed most efficiently? Which destinations performed sluggishly? What was the primary reason for the emails bouncing? What can be done to ensure maximum deliverability in the future?

In the email industry, deliverability reporting is crucial to maintaining and increasing the bottom line.  Deliverability reports indicate “issues” regarding deliverability. Specifically a report with fewer issues points to better overall deliverability and, consequently, a higher inbox placement rate.  Essentially, these reports provide “proof” that deliverability is effective across an entire active IP range, including VMTA pools.  This effectiveness could be extended with inbox monitoring or comparing open and click data across domains.

A few types of deliverability reports are discussed in more detail below.

Report Type A: Volume and Delivery Times

Measuring volume and delivery times (time from queuing to delivery), can determine the efficiency of sends, preparing you to answer questions from marketing or c-suite regarding volume capacity.  Due to the popularity of time-sensitive campaigns, such as price manipulated group purchasing campaigns, volume capacity and low latency is critical.  The ability to ascertain delivery times across your active IP range provides confidence that sends are efficient and that there are no “yield” signs or temporary blocks issued at the ISP level.  It is important to avoid these inefficiencies at the ISP level, as they can slow down the send and “curb your enthusiasm.”

Fundamentally, delivery times provide the exact time it takes for a particular queue to complete.  Knowing the average delivery speeds for a particular message helps marketing know how to manage particular types of campaigns.  Furthermore and into the future, understanding expected or estimated delivery timeframes across each IP, or pool will enhance collaboration between department heads. Understanding that ISPs and deliverability work in a dynamic environment, it would be beneficial for marketers to prognosticate expected delivery completion times.

Report Type B: Bounce Categories

Even today, bounce categorization is not standardized across all ISPs. Having said this, system bounce “codes” are less reliable than a description of the bounce reason. Thus, classification based on a “matched description” should have preference over an included mail system status code.  From a deliverability perspective, user unknowns and spam related categories need to be included in bounce descriptions.

For every sender, the inertia of temporary blocks is a common occurrence. However, the inertia of dealing with bounces is a more significant problem.  Reporting on bounce count and bounce rates per bounce category is essential for maintaining optimal efficiencies as well. Knowing the most frequent bounce categories, as well as dynamically modifying the queue with a command, can help increase efficiency.

Additionally, instituting real-time alerts from leading blacklists to help monitor your sends and quickly determine the reason why blocks occurred, coupled with parsing, helps identify and highlight certain inefficiencies at the onset. By instituting this process you will reduce man hours and improve overall efficiency.

A variety of granular reports make it less arduous to identify problem areas, the root cause of the problem, and what can be done to ensure that the same problem does not occur in future mailings. Bounces become easy to identify, at an individual level, a domain level, and a system wide level. Determining why the messages bounced is critical to your sending reputation, because emails that don’t get delivered cause more concern than those that do. Most commercial and carrier grade MTAs have a variety of canned bounce reporting programs that can really help streamline and optimize subsequent sends.

Report Type C: Groupings

All of these issues can be reported using groupings of the items discussed above.  Consolidated groupings are most important; they can be managed by envelope sender, vmta, or recipient domain.  Insight into these categories is important for deliverability because issues are often related to a particular sender, configuration, and/or specific domain.  Dissecting and splitting these KPIs usually makes these delivery issues more apparent.  Deliverability has a direct impact to your bottom line. Therefore, constant monitoring, analysis, and optimization are required to ensure optimal deliverability rates.  Every commercial MTA is different, but most have a useful reporting interface in place that should help you achieve the highest deliverability rates possible.  In closing, here is a list of other useful reports you might want to consider:

Delivery of top domains over a period of time
Delivery of messages per day/hour/second
Overview of volumes and bounces per IP range
List of top bounce categories aggregated by DSN
List of bounce related or spam related categories
Daily check and message count for “cold” VMTAs per domain
Message rates for specific IPs or VirtualMTAs and specific domains per hour, minute, or second
Breakdown of average message size, used to identify spikes (raw number per domain)
Feel free to indicate other reports you find most useful.

This article was inspired by Maarten Oelering of and Michael Weisel of

Fred Tabsharani

Port25 Solutions, Inc.


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