Switch with 100Mbit and 1Gbit ports - using its full capacity

Question

There are switches with mixed-speed ports, usually 24x100Mbit + 2xGbit, looking something like this: .

How are these different-speed switches internally connected? The point is, can you use multiple 100Mbit ports in full speed simultaneously to use the bandwith from the single Gbit port?

E.g., imagine that internet is connected to the Gbit ports and multiple workstations to 100Mbit ports. Can 2 workstations download with full speed and use 200Mbit from the Gigabit port together? Or is it still capped to 100Mbit due to the internal switching speed of the 100Mbit part?

Answer 1

How are these different-speed switches internally connected?

There's no standard way. Also, it doesn't really matter as long as the switch is non-blocking (which all modern single-chassis switches are).

can you use multiple 100Mbit ports in full speed simultaneously to use the bandwith from the single Gbit port?

Yes. The higher-rate ports are intended for uplinking (=connecting to a larger infrastructure), ie. in a fat tree topology. But you can use them in any way you see fit.

E.g. you could connect your main server and a fast (Internet) router to 1G ports and put clients and smaller servers on the 100M ports. Or use a 1G port to link to another switch. Or ...

A switch generally buffers network frames, decoupling transmit and receive rates. That way, a server can transmit a frame at 1 Gbit/s and a client on another port can receive the exact same frame at 100 Mbit/s (or vice versa). Accordingly, a sufficiently fast server linked at 1 Gbit/s can simultaneously feed ten clients at 100 Mbit/s at their full rate.