How to reduce packet loss?

A

arf9999

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Can anyone give me a suggestion on how to reduce packet loss. I upgraded the modem firmware to 4.2.1.8, and the packet loss decreased from around 25% to around 8%, but this still seems very high to me. Latency seems about the same at around 350-400ms.

If I upgrade to version 5 will I get any improvement? There doesn't seem to be any info on what version the towers are using....

Alternatively I could invest in some kind of antenna, but my signal is around 12% already and it seems from what I've read in the forums that this is ok.

MW128, Tower 50 (Northpark Plaza), 12% (No antenna)
 
By most accounts packet loss is linked to signal strength, thus an antenna should result in a more stable, less lossy connection. However there are antennae, and there are antennae!
The Fastcomm patch antenna is a piece of crap - don't even consider it. You could get a professional installation done, but its steep, and the outcome may not be much improvement.

Your best bet will be to make your own cantenna - quite a few ppl here use cantennae with good results. Search the forum for tips and help on making one.

<font color="blue">Telkom needs a leash, ICASA needs some guts, and the </font id="blue"><font color="red">SA consumer</font id="red"><font color="blue"> needs to make it happen</font id="blue">
 
Thanks,

Last night I tried the simple Pringles solution. Emptied the can, cut a slit and stuck it straight onto the modem antenna. After some manouvering, I increased signal strength to 19% and BER to 57%. Ping remains at average 350ms and I still get 5-8% packetloss. Could it be related to attenuation of the signal by traffic and/or vegetation (trees etc)?

Should I just accept that I'm losing packets along with my deathly slow download speed and stop wasting my time?





MW128, Tower 50 (Northpark Plaza), 12% (No antenna)
 
Packet loss is inherent to most wireless interfaces - mainly because of the vulnerability to interference, attenuation etc.

It would probably be worth your while spending more time on constructing a more "scientific" antenna, than your current slap-on pringles attempt - you can get very good results if the antenna is built right.
Try ProASM's antenna page for more info:
http://www.unrealza.co.za/proasm/wireless/antenna.html

The towers are running version 4.1.1 I think, so upgrading to version 5 could improve your side of things, but the tower will not improve. Despite this, some people have reported much better results using version 5 though, so its probably worth a shot.

Personally I wouldn't even consider spending any big money on antennae at this time. Until the speed issue is resolved, having a better connection won't help too much - there's no point chasing 0 packet loss when the speeds sit at 4kB/s [;)]

Finally, the speed issue is probably not something you can fix. The only thing you could try is to get your modem to connect to a different node of the tower - I believe GreedyFlyZA has reported getting better speeds out of different nodes of his tower - but don't hold your breath.
The root of the speed issue is Sentech - plain and simple - their call centre will try to fob you off, but everyone here knows who isn't holding up their end of the deal...


<font color="blue">Telkom needs a leash, ICASA needs some guts, and the </font id="blue"><font color="red">SA consumer</font id="red"><font color="blue"> needs to make it happen</font id="blue">
 
Another thing - about your pings. What sites are you pinging to get 350ms? If you are pinging international sites, 350ms is actually pretty decent.
Try pinging www.is.co.za or www.sentech.co.za - your pings *should* be under 200ms because of they are only a few hops away.

<font color="blue">Telkom needs a leash, ICASA needs some guts, and the </font id="blue"><font color="red">SA consumer</font id="red"><font color="blue"> needs to make it happen</font id="blue">
 
I current have an open ticket concerning these ping times. It seems that Mintek(12-JHB) gives rather crappy response times.

What I have noticed is that the "busier" towers have higher latency.... I'm in direct contact with Sentech support on the issue - not the call centre - so I'll keep you posted.

If you'd like to have a look at my comparative latencies : http://riggerman.dyndns.org/cgi-bin/smokeping.cgi

It's not always up and not always fast - it's hosted on MyWireless.
 
Lol - <b>"Not always up, not always fast"</b> that should be the MyWireless slogan

<font color="blue">Telkom needs a leash, ICASA needs some guts, and the </font id="blue"><font color="red">SA consumer</font id="red"><font color="blue"> needs to make it happen</font id="blue">
 
I understand the "not always up" part, but I can't relate to "not always fast". It supposes that at some stage MyWireless has been fast, I don't see much evidence of that[:(]

MW128, Tower 50 (Northpark Plaza), 12% (No antenna)
 
Just did the sanford speed test (for some reason I cannot get any of the local speed tests to work) got the following result:

WEB100 Enabled Statistics:
Checking for Middleboxes . . . . . . . . . . . . . . . . . . Done
running 10s outbound test (client to server) . . . . . <b>65.72Kb/s </b>
running 10s inbound test (server to client) . . . . . . <b>9.81kb/s </b>

------ Client System Details ------
OS data: Name = Windows XP, Architecture = x86, Version = 5.1
Java data: Vendor = Sun Microsystems Inc., Version = 1.4.2_04

------ Web100 Detailed Analysis ------
Cable modem/DSL/T1 link found.
Link set to Full Duplex mode
Information: throughput is limited by other network traffic.
Good network cable(s) found
Normal duplex operation found.

Web100 reports the Round trip time = 834.44 msec; the Packet size = 1418 Bytes; and
There were 2 packets retransmitted, 4 duplicate acks received, and 4 SACK blocks received
The connection stalled 1 times due to packet loss
The connection was idle 1.88 seconds (17.09%) of the time
This connection is sender limited 33.70% of the time.
Increasing the current send buffer (63.0 KB) will improve performance
This connection is network limited 66.29% of the time.
Contact your local network administrator to report a network problem
Contact your local network admin and report excessive packet reordering
Excessive packet loss is impacting your performance, check the auto-negotiate function on your local PC and network switch

Web100 reports TCP negotiated the optional Performance Settings to:
RFC 2018 Selective Acknowledgment: ON
RFC 896 Nagle Algorithm: ON
RFC 3168 Explicit Congestion Notification: OFF
RFC 1323 Time Stamping: OFF
RFC 1323 Window Scaling: ON
Information: Network Middlebox is modifying MSS variable
Server IP addresses are preserved End-to-End
Client IP addresses are preserved End-to-End

[xx(]

<b>So how do we report that there is a network problem???</b>

MW128, Tower 50 (Northpark Plaza), 12% (No antenna)
 
Hi af9999,

Im not a major pro when it comes to pings etc... so here goes anyway :-)

I noticed that the size of your packets sent for the ping was quite large [1418 bytes]. Due to the size of the packet being sent, your latency will be higher! With a standard ping test from a PC, it sends a packet size of 32 bytes. Perhaps reduce the packet size [to 32 bytes] and your ping test will return a lower latency value.

Hope this helps...

Syzygy78
 
The latest update I have received on my ticket is that there IS a problem with latencies and that some sort of upgrading needs to be done to fix this. It is supposed to be effected during the next week or so ...

Seeing is believing.

R
 
Hi Syzygy...Those stats are from Stanford Uni speed test....so the size of the packet was for speed testing not latency.

For normal pings with 32 bytes I get anything from 90 (the best) to 3500ms to www.sentech.co.za.

I think regardtv has about 50 tickets open at present about this, and has been informed that "we are working on the problem".... now where have I heard that before??

MW128, Tower 50 (Northpark Plaza), Signal:12%,S-N-L: 5, BER: 40%
 
Hehee,

The 1 positive thing I can say about my ticket is that I don't have ANYTHING to say to the call centre here. All communications are with IP/Radio engineers ;-) .. they mailed me directly and I've latched onto that e-mail like a pittbull ;-)

But, since I'm actually getting information I'm not going to reveal/abuse my contact there. I drop him a mail every couple of days to get an update... Will do so again on Tuesday ;-)

Will keep all posted.

R
 
During our wardrive excursions we were literally between 100-300 metres from each tower. Top signal strength. As good as it gets. There was ALWAYS packet loss.

So don't bother fiddling with your signal, and firmware, and whatnots later than 4.2.1.8 and perhaps a pringles can over the modem.

The problem isn't with you, and isn't anything you can do something about.

<center><h6> MyWireless <s>Hacks</s> Tweaks & Tech Info || Have you checked the fawking FAQ? <br /> <font color="red">Tired of Sentech's bad service? Want to compare speeds? We at least listen...</font id="red"></h6></center>
 
Does anyone know what would be an acceptable BER in order to cut down packet loss?
 
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