Designed and architected from the Main Library’s opening in 2005 through the carrier handoff in 2023.
Frame relay gave way to Metro Ethernet. Head-end bandwidth and quality of service were engineered explicitly rather than left to default — weighted random early detection, class-based weighted fair queuing and policing — and the public and private library subnets were separated. The whole estate was then rebuilt again as a numbered redesign project running two years, branch by branch, with a head-end relocation at the end of it.
A central library and its branches are an unusual estate to hold. Staff and public sit on the same physical plant, and unlike almost anywhere else in a government network, the public side is the entire point of the building. That inverts the usual priority: the segment carrying people who do not work here is the one that cannot be allowed to degrade.
Outcome
A public estate carried across two transport generations without the public side ever being the part that broke.