Giles Coochey wrote:
On 09/07/2011 01:06, Les Mikesell wrote:
Turning off negotiation pretty much guarantees problems if anything changes at the other end or you use an unmanaged switch. And the gigabit spec requires auto-negotiation.
Let me make it clear - auto-negotiation only works if auto-negotiation is configured on both sides. It does not work if one side hard codes the speed and duplex. Both sides have to be set for it to negotiate. Agreeing on speed and duplex ensures that it will work.
If something is going to change on the remote end without you knowing, or your provider is using an unmanaged switch then it's time to change provider :-) - they obviously are cheapskates and don't have any change management control on their systems.
Gigabit is different.
My reading of the spec is that when a port is configured for 1GbE over 1000BASE-T (copper), "disabling" auto-negotiation disables the advertising of the auto-negotiation for 10BASE-T and 100BASE-T, but auto-negotiation is still advertised and operational for 1GbE. Auto-negotiation cannot be disabled for 1000BASE-X (optical fiber).
Deviation from the spec would mean such kit is Ethernet-like. An ability to "set" auto-negotiation one way in the user interface while leaving the hardware in a different - standards conforming - state is possible.