Abstract: Provided are a method, system, and program for managing data transmissions at a local network device communicating with a linked network device over a network, wherein each network device is capable of transmitting data at different speeds. An operation is initiated to change a current transmission speed at which data is transmitted between the local and linked network devices in response to a speed change event. A determination is made of a new transmission speed different from the current transmission speed. A register is set in the local network device to indicate the new transmission speed. A speed change request and the new transmission speed are transmitted to the linked network device to cause the local and linked network devices to communicate at the new transmission speed, wherein the transmission occurs without terminating a linked exchange occurring between the local and linked network devices.

Abstract: A circuit to control a network interface includes a first interface circuit and a second interface circuit. The first interface circuit is capable of negotiating one protocol to use from a plurality of known interface protocols. The first interface circuit controls the network interface when the negotiated interface protocol is supported by the first interface circuit. Otherwise, if the second interface circuit supports the negotiated protocol, the first interface circuit releases control of the network interface to the second interface circuit. The first interface circuit takes control of the network interface from the second interface circuit when the second interface circuit signals the first interface circuit that reliable communication with the network has been lost.