SG-1000 throughput slow down

johnpoz

Well the one sniff has some issues - doesn't look like it caught the syn?

Clearly something going on there.. Would like to see cleaner sniffs and tests - and where exactly is the sniff being done at?

yendor

Hi,
The sniff was done on the laptop as I needed to bypass the SG-1000 for one of the test.

I can do another sniff from the SG-1000 if that would help? You also said you would like to see a clean capture? What would you like me to do here.

All I did on this sniff was to filter for the remote address in src and dst then ran it through a anonymiser for posting.

And yes I found a down load source that gives me a good speed on my ISP but as you see it still has a reduction through the SG-1000.

Thanks for having a look.

johnpoz

Clean in the fact the sg1000 sniff is missing the start of the conversation.. I show it seeming to miss the start of conversation.

So not sure if you caught the tail end of one speed test and then started another, etc..

But from sg1000 sniff having way smaller window size then yeah the speed of that speed test is going to be slower..

yendor

Thanks @johnpoz,
When I get chance I'll redo the sg-1000 sniff, do you have any ideas on why the windows size would be different?

The only thing I can think of is, I was lazy and ran my sg-1000 sniff over my home network i.e laptop->switch->switch->sg-1000->cable modem, I'll try the sniff directly connected to the sg-1000 next time to see if that helps.

For a bit of info:
The two switches ara a WNDR3709 running OpenWRT for AP and a GS108. The laptop was on a wired connection laptop->GS108->WNDR3709->SG-1000->Cable Modem.

stuck at work for the next 10-12hrs so I can't do any test for a bit.

yendor

Ok uploaded 2 more sniffs (got real slow connection tonight) same link pcapng files

this time I connected to the SG-1000 direct and then the cable modem direct, but may have to do the test once ISP network gets back up to speed.

anyways have a look and see if you see anything strange.

Thanks.

johnpoz

Your still not catching the start in the direct sniff.. But again your window resize are no where close to each other... So yeah no shit your download is going to be way slower!!

Your window size when your direct is huge compared to when your on the sg1000 per those sniffs

You running a proxy or something on pfsense? If I had to guess to why your seeing the smaller windowsize have to guess its due to your dupes or fast retrans..

Not allowing the windowsize to grow... But that is just a GUESS!!! If you want to benchmark the sg1000 and what it can do you really need to make sure environment is the same in both your tests. So take the isp and the internet out of the equation and put a server on your wan, and then your client on the lan -- do your speedtesting, iperf, download off a http, etc. But can promise you this if your window size is that small compared to when it grows large then yeah your going to see a real speed difference..

yendor

Ok run a test with ipef3 running on a RPI on the wan side, ran the test 3 time in each setup and the sniffs are only filtered on the RPI address 10.0.0.2 dis and src, so hopefully it should have got all the info.

Test 1:
PC->GS108->SG-1000->RPI: wireshark 20181012_Filter_SG-1000.pcapng

Test 2:
PC->RPI: wireshark 20181012_Filter_Direct.pcapng

Both file can be found at the same link pcapng files

Thanks.

johnpoz

you for such tests you don't need to capture the payload right... That way your sniff is not so LARGE..

What was the speed difference? HUGE amount of out of order packets? Which doesn't seem possible?? And still seeing what wireshark says are retrans and dupes, etc.. The direct see no window size updates they start out and stay there.. While the other tests shows lots of adjustments and higher than the 6000 was seeing before.

But something OFF in that sniff through the sg1000, I don't have a sg1000 but will try and test this weekend on how they should look going through firewall..

yendor

Thanks @johnpoz,
I'm kind of new to wireshark/sniffing and only have done the basics, how should I set it up to run the test. what are you looking for and what can I drop.

Thanks for your help.

johnpoz

in the interface options section just change the snaplen to something only a few bytes vs the default of the whole thing.. We really just need to see the headers we don't need all the data to troubleshoot what is going on.