|-----Original Message----- |From: Simon Perreault [mailto:[email protected]] |Sent: Thursday, August 11, 2011 8:38 PM |To: DENG Xiaohong ESP/PEK |Cc: [email protected]; [email protected]; [email protected] |Subject: Re: [Softwires] Clarification of the |stateles/stateful discussion | |On 2011-08-11 07:01, [email protected] wrote: |> But I don't understand will the figure be different with 'scattered' |> port-set NAT? To my knowledge, it's something todo with app's |> behaviours and NAT type(EIM in our test). Would you explain |if I miss |> something? Thanks | |As it was discussed in this thread [*], an EIM NAT will, in
Understood EIM behaviors. My point is port-range NAT or scattered port-set NAT is nothing to do with EIM. |theory, only be able to support a number of sessions roughly |equal to the number of external ports. That is because |internal hosts typically do not reuse source port numbers for |sessions to different destinations. Could you explain how this conclusion was drawed? According to [a], port usage in figure 3 and session usage in figure 4 show that, for Google Earth, port and session usage are roughly the same, while firefox session usage is roughly 1.5 times as port usage. | |If your tests show otherwise, it would be very important for |this working group to understand exactly why theory does not |match practice. BitTorrent and Skype are definitely cases that show othersiwse. As the detailed analysis I stated in the previous email, but don't mind to explain again: When BT Client initiates a downloading it first uses the same source port to connect to the different destinations (destination IP and port) therefore a source port multiplexing different sessions. Data shows maxium port usuage reaches 160, while session usuage continously stays above 450. Skype is another example that uses a source port to multiplex different sessions thereby introducing less source port than sessions on NAT. Data shows less than a couple of ports achieve more than a hundred sessions! But, don't ask me why, as niether did I write code for BT Client nor for Skype. ;0 [a] http://opensourcev6transtechnologies.weebly.com/experiments-results.html Cheers, Xiaohong --- Open-source PCP Client : http://opensourcev6transtechnologies.weebly.com/ A+P experiments results: http://opensourcev6transtechnologies.weebly.com/experiments-results.html IETF81 PCP demo page: http://opensourcev6transtechnologies.weebly.com/ietf-81-pcp-demo-site.html | |[*] |http://www.ietf.org/mail-archive/web/softwires/current/msg02461.html | |Simon |-- |DTN made easy, lean, and smart --> http://postellation.viagenie.ca |NAT64/DNS64 open-source --> http://ecdysis.viagenie.ca |STUN/TURN server --> http://numb.viagenie.ca | _______________________________________________ Softwires mailing list [email protected] https://www.ietf.org/mailman/listinfo/softwires
