Bandwidth

A 500 Mbps circuit is a capacity claim about the port or the contract. It is not the rate a given file move will sustain. RFC 6349 separates that capacity from measured TCP throughput, because the transfer rarely owns the whole path and protocol overhead takes a cut.

People sell and buy the wrong number. An office switch at 1 Gbps does not make a cloud upload run at 1 Gbps. The up link, often a fraction of the down link on consumer service, is the cap for file upload. The recipient's down link caps the later download. Quoting one side's plan for the other side's transfer is how deadlines slip.

A studio contract lists 1 Gbps. The useful upload to the platform measures 40 Mbps, because the building's up commit is 50 Mbps and other tenants are on it. A 30 GB master is 240,000 megabits. At 40 Mbps that is 6,000 seconds, about 100 minutes, before retries. The producer who divided 30 GB by 1 Gbps got four minutes and booked the review too early. Bandwidth here was 50 Mbps committed up. Throughput was 40. Neither was 1 Gbps.

Shared bandwidth is the usual case. A link-aggregation group can show a large capacity and still give one flow a single member's worth. A mobile radio can advertise a high peak and fall to a tenth of that in a minute. Capacity is a ceiling. Transfer throughput is what this session got. Latency is how long a round trip takes, which is a different axis: a satellite path can have huge bandwidth and a delay that hurts chatty protocols. Bandwidth throttling is a ceiling someone configured under the physical one.