WAN · Wide Area Network
The long-haul network between campuses; once a run outgrows any single powered site, WAN latency and bandwidth become a training-architecture constraint rather than an IT concern.
Current numbers
~1–2.5 usend-to-end RDMA fabric latency (NIC-to-NIC through one switch hop): InfiniBand ~1–2 µs, tuned RoCEv2 ~1.5–2.5 µs — microseconds, vs milliseconds for WAN