OpenWrt Forum Archive

Topic: low Wireless download throughput

The content of this topic has been archived on 29 Mar 2018. There are no obvious gaps in this topic, but there may still be some posts missing at the end.

I am using whiterussian on a Linsys WRT54Gl.

When I test the throuhput from a wireless host to a host wired on an Ethernet port of the router, I get 28Mbit/s in UDP (around 22 Mbit/s TCP), which is fine.

In the other way (from Ethernet to Wireless), I only get 7 Mbit/s UDP.  I had the same problem with RC5. There is no particular routing configuration set (no firewall, no QoS...).  The distance is short (a few meters), and there is no interference.

Did anybody experience the same problem?

An analysis of packets interarrival delays done with another wireless host in monitor mode shows that the minimum delay between the reception of packets on wireless is 595 microseconds (it should be 326µs), while the IEEE 802.11 slot is 143 microseconds (it should be 9 microseconds in 802.11g, or 20 in 802.11b).  Most packets are transmitted at 54 Mbit/s, as it should be.  Packet losses does not appear to be noticeable.

Could it be due to some weird configuration?  Or should I file a bug report? BTW, I got similar behavior with an Asus WG500p under DD-WRT, with a slightly higher bandwidth, whereas the same router performed normaly under the original firmware...

I forgot to say that I use version 0.9 of Whiterussian...

The answer to my question, just in case someone has the same problem and read me...

In the web configuration interface, in the Advanced Wireless Configuration tab, there is a parameter "Distance" wich default
to 20 Km.  This has the effect of defining Mac parameters consistently with the roundtrip time of the electromagnetic signal for this distance (133µs).  This parameter should be left undefined.

The discussion might have continued from here.