
Update on T-Mobile Network Issues (postmortem) - gen3
https://www.t-mobile.com/news/update-for-customers-on-network-issues
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gen3
"The trigger event is known to be a leased fiber circuit failure from a third
party provider in the Southeast. This is something that happens on every
mobile network, so we’ve worked with our vendors to build redundancy and
resiliency to make sure that these types of circuit failures don’t affect
customers. This redundancy failed us and resulted in an overload situation
that was then compounded by other factors. This overload resulted in an IP
traffic storm that spread from the Southeast to create significant capacity
issues across the IMS (IP multimedia Subsystem) core network that supports
VoLTE calls"

I find it interesting that rerouting telephony data was enough to take down
the system. I guess the event was something similar to when a small ISP breaks
their BGP and routes the entire internet (or a large chunk) through a network
that can not handle it?

