Network Setup:

• 8 Gb/s download / 1 Gb/s upload fiber connection
• VLAN100 (priority 0) for internet only, no IPTV/VoIP
• BE800 router
• LAN computers with 2.5 Gb/s NICs

Issue: When downloading from the internet on LAN computers with 2.5 Gb/s NICs, I'm experiencing:

• Download speeds around 2.35 Gb/s
• High number of TCP retries
• Issue doesn't appear on WiFi (which reaches ~1.5 Gb/s)
• Same behavior on both IPv4 and IPv6

Troubleshooting Done:

1. Tested multiple network cables
2. Tested different computers and NICs
3. Ran iperf3 tests between local computers through the BE800 2.5Gb/s switch:
   • Local transfers show 0 retries at 2.5 Gb/s
   • Multiple simultaneous internet connections still cap at 2.35 Gb/s with high retries
4. Verified iperf3 servers are 40 Gb/s and directly connected to my ISP
5. Other users with different routers achieve full 8 Gb/s speeds
6. ISP connection through SFPWAN port or 10GWAN port both same results

Test Results: Attached iperf3 results show 1425 retries over a 10-second test with uneven stream distribution (total throughput 2.35 Gb/s).

- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval           Transfer     Bitrate         Retr
[  5]   0.00-10.00  sec   101 MBytes  84.7 Mbits/sec   60             sender
[  5]   0.00-10.00  sec  98.6 MBytes  82.7 Mbits/sec                  receiver
[  7]   0.00-10.00  sec   106 MBytes  88.6 Mbits/sec  145             sender
[  7]   0.00-10.00  sec   103 MBytes  86.2 Mbits/sec                  receiver
[  9]   0.00-10.00  sec   424 MBytes   356 Mbits/sec  147             sender
[  9]   0.00-10.00  sec   420 MBytes   352 Mbits/sec                  receiver
[ 11]   0.00-10.00  sec   267 MBytes   224 Mbits/sec  124             sender
[ 11]   0.00-10.00  sec   264 MBytes   221 Mbits/sec                  receiver
[ 13]   0.00-10.00  sec   290 MBytes   243 Mbits/sec  151             sender
[ 13]   0.00-10.00  sec   287 MBytes   241 Mbits/sec                  receiver
[ 15]   0.00-10.00  sec   294 MBytes   246 Mbits/sec  169             sender
[ 15]   0.00-10.00  sec   291 MBytes   244 Mbits/sec                  receiver
[ 17]   0.00-10.00  sec   191 MBytes   160 Mbits/sec  118             sender
[ 17]   0.00-10.00  sec   188 MBytes   157 Mbits/sec                  receiver
[ 19]   0.00-10.00  sec   104 MBytes  87.0 Mbits/sec  116             sender
[ 19]   0.00-10.00  sec   101 MBytes  84.4 Mbits/sec                  receiver
[ 21]   0.00-10.00  sec  82.7 MBytes  69.3 Mbits/sec   79             sender
[ 21]   0.00-10.00  sec  80.4 MBytes  67.4 Mbits/sec                  receiver
[ 23]   0.00-10.00  sec   127 MBytes   107 Mbits/sec  127             sender
[ 23]   0.00-10.00  sec   123 MBytes   103 Mbits/sec                  receiver
[ 25]   0.00-10.00  sec   596 MBytes   499 Mbits/sec   83             sender
[ 25]   0.00-10.00  sec   590 MBytes   495 Mbits/sec                  receiver
[ 27]   0.00-10.00  sec   262 MBytes   220 Mbits/sec  106             sender
[ 27]   0.00-10.00  sec   259 MBytes   217 Mbits/sec                  receiver
[SUM]   0.00-10.00  sec  2.78 GBytes  2.39 Gbits/sec  1425             sender
[SUM]   0.00-10.00  sec  2.74 GBytes  2.35 Gbits/sec                  receiver

Questions:

1. Could this be related to VLAN handling on the BE800?
2. Is hardware acceleration working with VLANs?
3. Why am I limited to 6.5 Gb/s out of my 8 Gb/s connection?
4. Are there any settings I can optimize?

Any help would be appreciated.

Thanks!