This setting limits the network bandwidth that BITS uses for peercache transfers (this setting does not affect transfers ...

This setting limits the network bandwidth that BITS uses for peercache transfers (this setting does not affect transfers from the origin server).
To prevent any negative impact to a computer caused by serving other peers, by default BITS will use up to 30% of the bandwidth of the slowest active network interface. For example, if a computer has both a 100Mbps network card, and a 56 Kbps modem, and both are active, BITS will use a maximum of 30% of 56Kbps.
You can change the default behavior of BITS, and specify a fixed maximum bandwidth that BITS will use for Peercaching.

If you enable this setting, you can enter a value in bits per second (bps) between 1048576 and 4294967200 to use as the maximum network bandwidth used for peer-caching.

If you disable this setting or do not configure it, the default value of 30% of the slowest active network interface will be used.

Note: This setting has no effect if the "Allow BITS peercaching" setting is disabled or not configured.