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--- midd:traffic_scheduling:project_log [2009/03/29 17:28]
perryk
+++ midd:traffic_scheduling:project_log [2009/04/12 17:11]
perryk
@@ Line 81: / Line 81: @@
 ==== 03/29 ====
-Have real time capture on server working. Was a little more difficult than expected as the server doesn't have a complete picture of who is sending to it. It builds a time-based partner dictionary and filters packets based on who is in the dictionary. If no packets have been sent or received with a partner, the partner times out and is removed from the filter dictionary. Next step is to provide a data exchange mechanism between client and server where by one tells the other what it's packet history is.
+PK - Have real time capture on server working. Was a little more difficult than expected as the server doesn't have a complete picture of who is sending to it. It builds a time-based partner dictionary and filters packets based on who is in the dictionary. If no packets have been sent or received with a partner, the partner times out and is removed from the filter dictionary. Next step is to provide a data exchange mechanism between client and server where by one tells the other what it's packet history is.
+AB - Looked up useful SNMP variables. Information is on the [[midd:traffic_scheduling:metrics#SNMP|metrics page]].
+==== 03/30 ====
+Met for lunch. Discussed much.
+PK - Looked for TCP PUSH support in Windows (.NET). There isn't any. Zilch.
+AB - Investigated using C# on Linux. Mono looks feasible. Will try to get it running.
+==== 03/31 ====
+PK - it looks like SNMP won't be usable by us. a) It is hardware dependent - you must know what hardware you're talking to in order to use it b) it requires a known "community name" which works as a password - since we don't know it, we can't use it. :(
+PK - modified server to echo any TCP and UDP packets that it sinks. This made the partner stuff I added unnecessary and it has been removed.
+==== 04/02 ====
+AB - Attempt to test database connections with Python. No easy ODBC connectors for MySQL, so will have to do at home where I have more control over my development environment.
+==== 04/05 ====
+AB - Got Mono up and running for C# development on Linux. Connected to Perry's databases. Traffic analysis is next.
+==== 04/08 ====
+PK - researched and found a means of performing more high resolution timing in .net.
+==== 04/09 ====
+PK - Discovered that the Sprint mobile broadband card is invisible to winpcap. Researched this. Winpcap cannot see modem connections under Vista. Continued researching this on winpcap and sharppcap mailing lists. One fellow suggested bridging the Sprint card to the loop back connector.
+==== 04/10 ====
+I was in the process of doing this (see above) when I could not reinstall the Spring drivers. Looking for a new set of drivers, I found a completely revamped set from Spring. Installing, and guess what - the NDIS adapter can not be directly seen by winpcap. Successfully sending and receiving via our software over the Sprint card to our server.
+==== 04/12 ====
+Learned some fascinating things about Windows networking. The metric you specify in the network settings doesn't do diddly. If you really want to change network metrics you have explicitly set metrics in the routing tables. I wrote a large TCP block sender plug-in. This caused a lot of opportunity to reassess the capture code. And, finally, caused a lot of pouring over wireshark captures comparing them to mine. This caused some learning about D-Link NIC options. Get this, in order to get fast performance with my NAS I enabled Jumbo packets (9KB). This is OK - as the NAS and my machine (and my switches) all understand Jumbo packets. The router doesn't so the negotiation between my machine and the router drops packet sizes back to normal for that path.. Turned out I had some other option on - Large Packet Offload. This is REALLY how large packets happen (32KB). But THIS OPTION doesn't get negotiated. So, when I blast something out to the Internet, I get huge numbers of retries because I'm sending 32KB segments with the Don't Fragment flag set. So now I understand and can reconcile wireshark to my server and client logs. But I can't get optimum performance to my NAS and the Internet at the same time.  Spent 7 hours on this today.

WiNGS Lab @ UW

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