Summary
Microsoft's Smart Network Data Services (SNDS) is a crucial tool for email senders to monitor their reputation and deliverability at Outlook.com. However, many senders, even those with high sending volumes, report inconsistent or incomplete data from SNDS. This can make it challenging to gain a full picture of their email performance and diagnose potential issues.
Key findings
- Observed inconsistency: Many senders report seeing SNDS data for only a few days out of the month, even when sending daily, high volumes.
- Volume thresholds: SNDS has a minimum volume threshold (e.g., 100 messages/day to Microsoft) that must be met for data to appear, though high-volume senders still face inconsistencies.
- Data purpose: SNDS is primarily a reputation monitoring tool, not a detailed volume analytics platform, which may explain why its volume reporting isn't as granular or consistent as expected.
- Shared IP challenges: On shared IPs, the reported volume reflects all traffic, not just an individual sender's, making it harder to isolate personal sending patterns and potentially leading to less specific data if individual volumes are low within a high collective volume.
- Delayed updates: Data can be delayed or intermittently updated, which might cause it to seem incomplete.
Key considerations
- Set realistic expectations: Understand that SNDS is a reputation tool and may not provide the precise, consistent volume data seen in dedicated email analytics platforms.
- Combine with other metrics: Supplement SNDS data with internal sending logs, ESP reports, and other postmaster tools like Google Postmaster Tools for a comprehensive view.
- Monitor deliverability rates: Prioritize actual inbox placement and engagement rates at Microsoft domains, as these are more indicative of real-world performance than just SNDS volume reporting. If you're seeing good delivery rates, the volume inconsistency in SNDS might not be a critical issue.
- Understand data access: For more information on accessing data for specific platforms like Salesforce/ExactTarget, refer to resources on SNDS and JMRP data for Salesforce/ExactTarget users.
- Review Microsoft's official guidance: Consult Microsoft's Postmaster site for any updates or specific information regarding data availability and thresholds.
What email marketers say
Email marketers often rely on SNDS for a quick glance at their sender reputation with Microsoft. However, the observed inconsistency in volume data can lead to confusion. Despite sending millions of emails daily, some marketers find that SNDS only provides data for a limited number of days each month, leading to questions about the tool's reliability for consistent volume tracking.
Key opinions
- Limited daily data: Many marketers experience SNDS providing data for only 4-8 days a month, even with continuous, high-volume sending.
- Discrepancy with actual delivery: Some find that despite inconsistent SNDS volume reporting, their actual email deliverability (opens, clicks, inboxing rates) at Microsoft domains remains strong.
- Focus on deliverability: The primary concern for marketers is successful inbox placement, and if that's healthy, inconsistent SNDS volume data might be less of a critical issue.
- Under-utilization of SNDS: Some marketers rarely check SNDS, suggesting that if deliverability is good, minor data inconsistencies are often overlooked.
Key considerations
- Holistic view of reputation: Don't solely rely on SNDS for your sending metrics. Utilize your ESP's analytics and other reputation tools.
- Analyze volume fluctuations: Be aware of how email volume and volume fluctuations affect deliverability and sender reputation overall, not just as reported by SNDS.
- Investigate if deliverability suffers: If inconsistent SNDS volume data correlates with a drop in actual inbox placement at Microsoft, then it warrants deeper investigation into why the data is not displaying or if there are other underlying issues.
- Understand reporting nuances: Recognize that SNDS data is typically high-level and might not provide daily, granular breakdowns for all IPs, particularly when dealing with shared IP space.
Marketer view
Marketer from Email Geeks states that even with clients sending millions of emails daily, they only observe SNDS data for a small fraction of the month, raising questions about whether this is the current norm for the service.
Marketer view
Email marketer from RatersEdge suggests that SNDS is particularly useful for high-volume senders, but acknowledges that data might not display properly for lower volumes, implying a threshold for consistent reporting.
What the experts say
Experts in email deliverability acknowledge that SNDS data can sometimes appear inconsistent, even for high-volume senders. They point to factors like the service's intended purpose, volume thresholds, and the complexities of IP reputation, especially for re-used or shared IP addresses, as reasons for these perceived discrepancies.
Key opinions
- Minimum message threshold: Some experts confirm that a minimum volume (e.g., 100 messages/day to Microsoft) is generally required for SNDS to display data, which can explain why low-volume senders might see gaps.
- Historical IP issues: SNDS might show old reputation issues for IPs that haven't sent mail recently but were previously associated with poor sending practices, even if the IP is now blocked (port 25) or inactive.
- Not a volume tracker: Experts reiterate that SNDS is a reputation and feedback loop tool, not a precise accounting of every email sent. Its primary goal is to help senders understand their standing with Microsoft.
- Observation bias: Inconsistencies might go unnoticed unless actively looked for, suggesting that for many, SNDS data is sufficient as long as deliverability is maintained.
Key considerations
- Understand data limitations: Recognize that SNDS provides aggregated data focused on reputation, not necessarily granular, real-time volume statistics for every single mail stream. For more details on this, see how reliable SNDS data is.
- Verify sending thresholds: If volume data is scarce, confirm that your sending volume to Microsoft IPs meets the often-cited minimum requirements for data to appear in SNDS. Check the general volume requirements for SNDS.
- Examine IP history: If an IP shows strange blocklist or reputation warnings despite low or no recent sending, consider its historical use. This is common with recycled IPs.
- Focus on actual performance: As long as emails are reaching the inbox and engagement is high, minor SNDS reporting gaps might not be indicative of a significant deliverability problem. Sometimes, SNDS reporting can contradict observed deliverability, as discussed in instances like SNDS data contradicting IP warming results.
- Consult official documentation: For the most accurate interpretation of SNDS data and any changes to its reporting, always refer to Microsoft's official SNDS support or FAQs for current guidelines.
Expert view
Expert from Email Geeks states they haven't seen changes to the reliability of SNDS data, but questions whether the initial sender's clients are consistently meeting the 100 messages/day minimum, implying this threshold is key to consistent data.
Expert view
Expert from SpamResource explains that inconsistent volume data in reputation services can often be attributed to thresholds where if an IP doesn't send above a certain volume, it might not generate daily reports.
What the documentation says
Microsoft's Smart Network Data Services (SNDS) documentation and related industry guides often describe it as a reputation and feedback loop tool. While it offers insights into IP status, complaint rates, and spam trap hits, it's not explicitly designed as a real-time, granular volume tracker. This core function can explain why senders might observe inconsistent volume data, particularly when their sending volumes are below certain thresholds or when their IPs are part of a larger shared pool.
Key findings
- Reputation focus: Official descriptions emphasize SNDS's role in monitoring IP reputation and identifying spamming activity, not providing precise daily email counts.
- Log file data: SNDS data is derived from the log files of Microsoft mail systems, which might aggregate data in ways that don't always reflect exact daily send volumes for individual IPs, especially lower-volume senders.
- IP-centric, not sender-centric: The data is primarily about IP activity and isn't filtered by individual sender or domain, meaning shared IP pools might show collective volume rather than individual sender contributions.
- Threshold considerations: Some documentation implicitly or explicitly mentions that data might only appear once a certain volume threshold is met or if specific activity warrants reporting.
Key considerations
- Understand the data's purpose: Recognize that SNDS is a reputation management tool first and foremost. Its goal is to help you maintain a healthy sending reputation, not to provide detailed analytics on every message. For more context, read about SNDS data reliability.
- Check volume requirements: Confirm any published minimum volume requirements for data to be displayed within SNDS. If your sending volume is too low, this could be a reason for missing data. This also applies to Google Postmaster Tools.
- Interpret shared IP data carefully: If you're using a shared IP, remember that SNDS data will represent the collective traffic from that IP, not just your specific sends. This can make individual volume tracking less precise.
- Consult official Microsoft resources: For the most accurate and up-to-date information on how SNDS operates and how its data is reported, always refer directly to Microsoft's official documentation and support channels.
Technical article
Documentation from Mailgun states that SNDS is a service designed to monitor and manage sender reputation by providing high-level insights on spam complaints, spam trap hits, and SmartScreen filter dispositions, implying its focus is on reputation metrics rather than raw volume.
Technical article
Twilio's insights documentation indicates that SNDS contains data about IP activity that is not filtered by sender or domain, suggesting that volume seen on shared IPs will be aggregated and might not reflect individual sender volumes accurately, contributing to inconsistency.
Related resources
9 resources
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Why is Microsoft Outlook.com email deliverability inconsistent and how reliable is SNDS data?
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Why does Microsoft SNDS data contradict email deliverability during IP warming?
Why is Microsoft SNDS data not displaying or delayed?
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