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These domains receiving our emails are rate-limiting us. The practice of rate-limiting is to combat spam messaging. If a service sees that they are receiving many emails from another domain, they will automatically bottleneck the sender because it is assumed that they are receiving a flood of spam messages.
Why now?
The introduction of the Alumni Forwarding Service greatly increased UConn’s email output. The AFS system automatically redirects all incoming emails that are sent to alumni to the alumni’s personal email address. This redirect causes UConn to send many emails Over time, the amount of emails has steadily increased. UConn sends much of this email to external domains, possibly many emails in a small timeframe (e.g. Listserv). At some point, we cross the thresh hold with a given domain and they institute throttling.
Solution
While UConn has no sway over other company's rate-limiting policies, we can take steps to improve our email security posture. There are several steps that need to happen first before we can accomplish this however and as of this writing there is no timeline.
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