On 2007-01-03 16:55, Iljitsch van Beijnum wrote:
On 3-jan-2007, at 16:33, Brian E Carpenter wrote:Explain why TCP will react any differently to a sudden path change due to shim6, compared to a sudden path change for any other reason. I don't understand what is specific to shim6.The difference is that with shim6, we get to avoid massive congestion when failing over from a very fast to a very slow path.
I'm sorry, why is that different from regular routing failing over from
a very fast to a very slow path? There's something I am completely
missing here.
Brian
If there is no consensus for a general recommendation for slow start when failing over, maybe we can make this specific to the situation where a host fails over from a fast to a slow interface:"When the shim protocol triggers the selection of a new path, and this path utilizes a lower-bandwidth interface than the interface of the prior path, it is recommended that the TCP window for any affected TCP sessions are reduced relative to the reduction in interface bandwidth. Alternatively, TCP slow start can be initiated. For non-TCP protocols, similar measures are recommended where available."