I have been asked to provide statistics on how long a TCP session for certain clients on various regions of our global network would remain open for before the TCP session times out (when data is in transit). This is using Microsoft TCP stacks as all client/server machines are running win2k with max-tcp-retransmissions set to 5. This is for a very time sensitive pricing application.
TCP RTO Timer. (RFC2988)
TCP retransmissions are based on RTO calulations.
At TCP startup, the RTO is set to 3 secs, (this is when no RTT measurement has been made)
RTO calulations is based on SRTT and RTTVAR values. "RTO = SRTT + max (G, K*RTTVAR)"
(2.2) When the first RTT measurement R is made, the host MUST set
SRTT <- R
RTTVAR <- R/2
RTO <- SRTT + max (G, K*RTTVAR)
where K = 4.
G is Clock Granularity.
Two questions :-
How often is RTO calculated within a TCP session, I assume that the RTO changes with every TCP ACK back from the receiver to the sender. Could someone please claify this.
What is G set to in most TCP implementations? Surely it has to be 1 or more? Can someone explain this component for me?
This is actually a pretty cool feature, i didn't even know it existed until I was looking for a solution to advertise a subnet (prefix in BGP talk), only if a certain condition existed. This is exactly what conditional advertisements does
j ai une question j ai achete un routeur cisco 887VA-k9 , je le configuré avec la configuration ci- dessous
si je le lier avec mon pc portable sur l un de ses ports directement ça marche toute est bien ( la connexion internet + m...
Attached policy provides CLI access to the Cisco 4G router over text messaging. Two files are in the attached .tar file:
2. PDF with instructions on how to load and use the .tcl file.