To stop an email storm (reply allpocalypse), Microsoft is rolling out an advanced version of Reply All Storm Protection. This feature is introduced to detect email storms automatically. But what are they and how do they affect organizations?
Reply all storm NDR will look something like the screenshot
What is an Email storm?
A sudden spike in “reply all” messages that trigger a chain reaction of email messages is email storms. These storms happen if anyone from the distribution list forgets to BCC and replies to the entire list followed by other members on the list to start responding. The inflow and load of these emails can make email servers inoperative.
The first email storm was triggered in 1997 by a Microsoft employee when he noticed he was on a list of Bedlam DL3 and emailed the list asking for removal. This list had 13,000 email addresses, and when others received the mail, they too started replying and requesting removal due to which 15 million emails were sent, and it consumed 195 GB of traffic. After this, another email storm-generated in 2007 at the U.S. Department of Homeland Security causing 2.2 million messages to be sent exposing the name of security professionals.
To date, there have been several instances of email storms, the latest of which took place in 2019.
Keeping these issues in mind and to stop them from happening Microsoft released Reply All Storm Protection.
How will New Reply All Storm Protection help?
This new feature will prevent email storms from throttling organizations’ email systems.
Reply All Storm Protection in #MSExchange Online is now available! Not sure you can test it without giving yourself a career defining moment, but it’s there – honest! https://t.co/PniCt95shr pic.twitter.com/enSPwlSP66
— Greg Taylor (@gregtaylor_msft) May 7, 2020
How will Reply All Storm Protection to Exchange Online work?
When a likely Reply All storm will be detected by Exchange Online, it will block the following Reply All attempts and will reply with a Non-Delivery Report (NDR) to the sender. When 10 Reply Alls to over 5000 recipients within 60 minutes are detected Reply All Storm Protection will block replies to that thread for 4 hours.
This is just the beginning, Microsoft is working to improve the tool so that a broader range of organizations benefit from the new Reply All Storm Protection feature.
Will there be any future enhancements to this feature?
To improve reply to all detection accuracy, Microsoft is considering making some future enhancement. In the coming time, we may see customizable thresholds and block durations. Eventually, organizations will get reply-all storms reports and notifications.
Is this announcement related to the rebranding of Office 365 to Microsoft 365?
Indeed, this announcement is just one of the many updates to the Microsoft 365 suite. And with this one thing is clear Microsoft will be investing in the suite this year, and the company is all in on this new change.
The first version of the feature has already seen reducing the impact of reply all storms, and as the feature will be updated, we will see it vanishing. This new feature will surely benefit large organizations and will protect them from email storms.