[lwip-users] Possible Issue with tcp

[DuBose, Chadwick]

 

Hi,

 

I have a project that uses lwip and I’m running into a little trouble. I’m using iperf to test the throughput. Currently, when IPV6 is disabled, my through put is fine. When it is enabled, my throughput drops significantly.  (~17.5 Mbits/sec to ~ 318 Kbits/sec).  Below is an excerpt from using Wireshark to watch the traffic.

No.     Time    Source            Destination   Protocol     Length Bytes in flight Calc window size   Info

182  21.569596  192.168.1.106  192.168.1.145  TCP           1514    5840             65535              [TCP Window Full] 60067  >  9100 [ACK] Seq=14637 Ack=1 Win=65535 Len=1460

183  21.570669  192.168.1.145  192.168.1.106  TCP           60                      5840              9100  >  60067 [ACK] Seq=1 Ack=11717 Win=5840 Len=0

184  21.570670  192.168.1.145  192.168.1.106  TCP           60                      5840              [TCP Dup ACK 183#1] 9100  >  60067 [ACK] Seq=1 Ack=11717 Win=5840 Len=0

185  21.570682  192.168.1.106  192.168.1.145  TCP           1514    4380             65535              [TCP Out-Of-Order] 60067  >  9100 [ACK] Seq=11717 Ack=1 Win=65535 Len=1460

186  21.570720  192.168.1.106  192.168.1.145  TCP           1514    5840             65535              [TCP Window Full] 60067  >  9100 [ACK] Seq=16097 Ack=1 Win=65535 Len=1460

187  21.572891  192.168.1.145  192.168.1.106  TCP           60                       5840              [TCP Dup ACK 183#2] 9100  >  60067 [ACK] Seq=1 Ack=11717 Win=5840 Len=0

191  22.310334  192.168.1.106  192.168.1.145  TCP           1514    5840             65535              [TCP Retransmission] 60067  >  9100 [ACK] Seq=11717 Ack=1 Win=65535 Len=1460

192  22.312520  192.168.1.145  192.168.1.106  TCP           60                       5840              9100  >  60067 [ACK] Seq=1 Ack=13177 Win=5840 Len=0

 

Is there any idea as to would could be causing the throughput to decrease?

Any help would be greatly appreciated.

 

Thanks