Embodiments of the present invention are directed to providing configurable transmission rates for devices within a multi-device enclosure, despite common communication media within the multi-device enclosure that would otherwise constrain or fix the transmission rates of the devices. In one embodiment of the present invention, implemented within a virtual-connect manager or other module or device contained in, or associated with, a multi-server enclosure, the virtual-connect manager provides an administrative or management interface through which each server can be assigned a maximum transmission rate. The virtual-connect manager then continuously monitors the transmission rates of servers and/or ports within servers in order to apply back pressure, or flow control, so that the servers and/or ports within servers do not exceed the configured maximum transmission rates.