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Re: [dccp] A quick question about sequence validity windows



Yep!  Specifically, we assume a receive buffer.

Eddie


Xiaofeng Han wrote:
Hello Eddie

thanks for your reply.

In my question, the lower bound I mean is GSR+1-(W/4), since new data is coming, the GSR increases, some data with sequence # smaller than the new GSR+1-(W/4) becomes out of the range of the window.

If I understand correctly, there is actually another buffer to store the data, the sequence validity windows is something like a filter to control the incoming data, but it has nothing to do with the data in the other buffer, is this understanding correct?

thanks again

xiaofeng

On Wed, 30 Nov 2005, Eddie Kohler wrote:

Hi,

The sequence window does not affect data that has already been received and enqueued. It should remain enqueued for the application until the kernel decides to get rid of it.

As for new packets that are older than the low edge of the sequence window: such packets should be processed according to the specification -- i.e., the receiver responds with a DCCP-Sync and otherwise ignores them. Such data will NOT be sent to the application.

Eddie


On Nov 29, 2005, at 12:12 PM, Xiaofeng Han wrote:


Hello

I have a question about sequence validity window, and would greatly appreciate it if someone could help me.

If I understand correctly, the sequence validity windows will slide forward if the receiver keeps receiving new data, because the GSR(greatest sequence number increase).

My question is, if this is true, some datagrams (old data around the low bound of the window) may become out of the range of the windows, in this case, what should we do about these data? drop them or send them to the application layer?

thanks

xiaofeng