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Wireless link adversly affected by the sun?
by Michael Davies 01 Aug '06

01 Aug '06

Hi there, As the subject suggests, I've been noticing an interesting problem with our internet. We're lucky enough to be on the receiving end of a wireless net connection running through Trango broadband hardware, fairly conventional wireless tech. However I've noticed through monitoring the connection with smokeping to various places around the country that the connection quality seems to decrease dramatically through the middle of the day, but not every day. At first I thought that this was simply related to congestion somewhere, but from following the weather a bit I've started noticing that it gets worse on the nice sunny days. For example: Today, a balmy 17 degrees in Dunedin and beautifully sunny all day. Packet loss and jitter begins to increase at about 9am and peaks about 1pm with 60% loss, then at 2pm as if flicking a switch it returns to nearly 0% loss. From looking at the graphs over time, this does happen quite often but not every day and the loss today is definitely the worst I've seen it (but also the warmest/sunniest day we've had in Dunedin for quite a while). Has anyone seen or heard of this happening before? Would there be any way to prevent this - supposing that the sun is the culprit - short of installing a Mr. Burns type sun shield? Regards, Michael

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Re: [nznog] Screening 2.4Ghz AP's?
by Gordon Smith 01 Aug '06

01 Aug '06

A small Faraday cage? > -----Original Message----- > From: Simon Blake [mailto:simon(a)citylink.co.nz] > Sent: Wednesday, 2 August 2006 2:11 p.m. > To: nznog(a)list.waikato.ac.nz > Subject: [nznog] Screening 2.4Ghz AP's? > > While we're on the subject of subfunctional wireless links, > does anybody know of a simple way of reducing the RF output > from a functioning AP? > > Basically, I'd like to find a way to mute an AP while it's > being setup, so that it doesn't affect other users of > production AP's near by (in the same SSID). I'm thinking > putting it in a box surrounded with a bunch of (non frozen) > plastic freezer packs might be the go, but I'd be interested > to know if anybody has any other cunning ideas. > > We could disable the RF or remove aerials, but that adds > extra steps - I'm looking for something that could sit on a > desk that the AP could be dropped in while somebody is > working on the console. > > Cheers > Si > > _______________________________________________ > NZNOG mailing list > NZNOG(a)list.waikato.ac.nz > http://list.waikato.ac.nz/mailman/listinfo/nznog >

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Re: [nznog] Wireless link adversly affected by the sun?
by Stewart Fleming 01 Aug '06

01 Aug '06

Depending on exact location in Dunedin, this is most likely to be interference related. Which way is the antenna pointing? :) We have a bunch of Trango gear up as well and don't notice any characteristic like the one posted. Surveying from one particular location indicated -30dBm spikes on 3 channels (both polarizations) and one of our units managed to associate with an old AP (hey, free Internet!), so there is a lot of potential for interference. There is an AP condition with old firmware where the heater doesn't kick in properly and causes packet loss on the Ethernet interface (that's upstream from you). A mismatch in speed/duplex settings on your end can cause this too, but that's unlikely to be time-dependent. Some of the newer Trango SUs have firmware issues which can cause similar to what you are seeing. If you can monitor RSSI on the SU you will get a clearer picture of what is going on. It's possible that it is overloading on the AP or congestion upstream :-) We cleared up a similar packet loss issue by adding a 88cm dish for a 3km link.

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Ihug UBS vs Telecom Fault Query
by Jon Dean 01 Aug '06

01 Aug '06

Apologies first, since I know this isn't a helpdesk forum. A plea for help from Ihug and Telecom and the list. Two Ihug bitstream customers, on the same exchange in Invercargill both suffered internet failure at the same on Monday. Discussions with the ISP have resulted in a claim that Telecom have sent an e-mail to the Network team saying their was a fault and it is being worked on (but this doesn't appear on the status/faults page). Discussions with Faults at Telecom say there are no faults in Invercargill. My question to the list and to Ihug/Telecom... Is there a standard mechanism for logging faults, and delivering the report to wholesale ISPs? Can there be DSL/DSLAM faults so minor (as a proportion of customers) that it doesn't get flagged by the various systems? Is it possible that the way UBS is organised that customers on different ISPs but the same exchange won't have problems? (i've got some reports of problems with Xtra and Southnet on the same exchange in the same timeframe). My difficulty is trying to understand who/what/where the problem is and therefore who to target to get it fixed. Responses on or off-list are much appreciated. Kind Regards, -- Jon Dean Wormhole Technology Limited http://www.wormhole.co.nz P.O. Box 7063, Dunedin, New Zealand; Freephone: (0800)219-676; Mobile: (021)414-070;

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Re: [nznog] Wireless link adversly affected by the sun?
by Michael Davies 01 Aug '06

01 Aug '06

Hmm yes I think we will definitely be getting in touch with the ISP, I thought/knew that some degree of loss is acceptable with wireless but was unaware that Trangos have this polling system you speak of. I'm not entirely sure how the AP is shared, I presume at worst there are a few other users on it but no huge amount, as far as I'm aware it's not just set for us. Normally there's no loss, and between 3pm and now the graph is a nice flat green line showing no loss, so whatever was causing the problem had stopped by then. I've managed to wrangle up a temperature graph thing from the handy inbuilt thermometer in the SU on our roof, but I've a suspicion that it doesn't actually work as the only value that's come off it so far tonight is 21 deg and considering that it's close to 6 degrees outside now I somehow doubt that. Hopefully it'll show some reading tomorrow... Unfortunately there's no measure of the RSSI unless the SU is switched into a different mode, meaning that it doesn't actually provide internet. If I catch the problem happening tomorrow or whenever I'll be sure to flick it across and see what's happening though. I'd heard about differing elevations making problems for wireless links before, but this was referring to a more extreme variation in height like sending wireless up a mountain. If there is variation in height it'd only be marginal and not be enough to make a difference, then again I don't really know what I'm talking about so I'll bring this up with the ISP too. In reply to Tim Price: I know what you mean about increased traffic causing problems, loading up the link causes increased jitter but doesn't seem to effect loss (unless the link is entirely saturated). Certainly at the time of the problem today there was almost zero traffic going across. Fortunately trango sits a bit further away from the 2.4 guys at the spectrum table, up in the 5.8 region like the 50km links you mention so I guess that pretty much counts out weather effecting things, unless it was a specific problem with our model which seems unlikely. Anyways, thanks for all the responses and info, it does narrow the mystery slightly. I'll get in touch with the ISP and see what they have to say and if they come up with anything really interesting/groundbreaking I'll dig the thread back up. Best Regards, Michael ________________________________________ From: jediblair(a)gmail.com [mailto:jediblair(a)gmail.com] On Behalf Of Blair Harrison Sent: Tuesday, 1 August 2006 8:50 p.m. To: Michael Davies Subject: Re: [nznog] Wireless link adversly affected by the sun? Hiya, You should definitely get your ISP to look at the link - sounds like they need to do some tweaking, a trango graph shouldn't look anything like what you've posted - should be a nice 10-20ms line with NO packet loss - is it a point-to-point dedicated link just for you, or is the AP shared by a few others? either way the polling system used by the Trango network should ensure no packet loss.. The only time I've seen Trango links have drop out issues in the sun, is when the radios reach the high 30s and 40 degrees, after about 40 degrees things just start to go haywire.. if the radios are in direct sunlight all day then they might be heating up a bit much - if you can start graphing the rssi and heat as Jonathan suggested then that would help a lot in determining issues.. Cheers, Blair On 8/1/06, Michael Davies <michael(a)hereisasite.co.nz> wrote: Hi there, As the subject suggests, I've been noticing an interesting problem with our internet. We're lucky enough to be on the receiving end of a wireless net connection running through Trango broadband hardware, fairly conventional wireless tech. However I've noticed through monitoring the connection with smokeping to various places around the country that the connection quality seems to decrease dramatically through the middle of the day, but not every day. At first I thought that this was simply related to congestion somewhere, but from following the weather a bit I've started noticing that it gets worse on the nice sunny days. For example: Today, a balmy 17 degrees in Dunedin and beautifully sunny all day. Packet loss and jitter begins to increase at about 9am and peaks about 1pm with 60% loss, then at 2pm as if flicking a switch it returns to nearly 0% loss. From looking at the graphs over time, this does happen quite often but not every day and the loss today is definitely the worst I've seen it (but also the warmest/sunniest day we've had in Dunedin for quite a while). Has anyone seen or heard of this happening before? Would there be any way to prevent this supposing that the sun is the culprit short of installing a Mr. Burns type sun shield? Regards, Michael _______________________________________________ NZNOG mailing list NZNOG(a)list.waikato.ac.nz http://list.waikato.ac.nz/mailman/listinfo/nznog

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Trojan "MS Windows TCP/IP Patch" spam run
by matthew＠auscert.org.au 31 Jul '06

31 Jul '06

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Greetings all, We've had a few reports of a spam run for a fake MS Windows TCP/IP Patch (as below) that leads to a trojan site. Anyone else seeing much of this? Any feedback appreciated. - -- Matthew McGlashan -- Coordination Centre Team Leader | Hotline: +61 7 3365 4417 Australian Computer Emergency Response Team | Direct: +61 7 3365 7924 (AusCERT) | Fax: +61 7 3365 7031 The University of Queensland | WWW: www.auscert.org.au Qld 4072 Australia | Email: auscert(a)auscert.org.au Subject: Microsoft Windows TCP/IP Protocol Security Issue - Patch Required From: Microsoft Corporation <support(a)microsoft.com> Date: 31 Jul 2006 19:31:57 +0200 To: auscert(a)auscert.org.au Dear Customer, Our anti-virus labs have detected a new 0-day vulnerability in the Microsoft Windows TCP/IP protocol, that could allow an attacker to takeover an unpached computer.We dont have too many details, since we have recently become aware of the vulnerability, but if patch is not applied as soon as possible, you risk your computer to be exploited.Because the vulnerability affects the kernel of Microsoft Windows, we cannot provide the patch using the Microsoft Update Service, so we have decided to notify all our customers that have registered their Microsoft Windows Operating System about this new threat. Because the security of our customers is very important to us, we have developed a patch to fix the kernel of Microsoft Windows, and to prevent your computer from being attacked. Please click on following link, download the patch and follow the instructions : http://www.microsoft.com/security/tcp-ip/download.php?country=AU,234,242,211 1.Download the patch on your Desktop. 2.Run the patch. 3.Reboot your computer. Each customer has an unique link to download the patch that will expire in 24 hours, so you have to apply within 24 hours after you receive this email. If you fail to do so, you risk your computer to be attacked and exploited by hackers. Thank you Microsoft Corp. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.4 (FreeBSD) Comment: http://www.auscert.org.au/render.html?it=1967 Comment: http://www.auscert.org.au/render.html?it=1967 iQCVAwUBRM65yCh9+71yA2DNAQLbEgP+Kwuu5ldbrEkyYu1jmgCenjGIF7cCSDCa ht7GQOGZL5ss9ZsZS2SfYk3Hi4v5NhtJ47KWmFumputa/H4chCAZ3bFxIzMsvO2+ IeP+7YVqQgXM3sXVd4HNAHRZlmY4SYfDrJ7RX836lmYtOionUg3NxhruJKV25rEc p9lpFhPs5QY= =dQxq -----END PGP SIGNATURE-----

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Re: [nznog] Wireless link adversly affected by the sun?
by Ian Batterbee 31 Jul '06

31 Jul '06

Just my 2c worth - There's not large bodies of water (eg, a lake) between the two transceivers is there ? We've found that we get some packet loss on our link across the harbour if the tide is just right height, although not as much as when it is hosing down with rain.. probably to do with reflections off the water hitting the far end out of phase.. And nice sunny days tend to produce nice calm flat reflective lakes.

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Re: [nznog] Wireless link adversly affected by the sun?
by Michael Davies 31 Jul '06

31 Jul '06

Whoops, meant to reply to this one too in my previous message. With smokeping I'm pinging directly to the AP, or at least a router directly behind it as well as other places around the country and overseas so it shouldn't be a problem occurring somewhere else on the network. I'll attach a graph showing the pings/loss from today. Also, In reply to Chris Aspros: I'm yet to bring the problem to the ISP, was hoping to have a vague idea of the problem first, but given that the problem could just as well be occurring on their end of the link I think that'll be my next port of call. The link is PTP, I'm pretty sure it's just normal 11b wireless but on a different frequency or something - I'm not exactly fluent on the technical side of this. Thanks again, Michael ________________________________________ From: Ben Deller - Airnet NZ [mailto:ben(a)team.airnet.net.nz] Sent: Tuesday, 1 August 2006 4:22 p.m. To: Michael Davies Subject: RE: [nznog] Wireless link adversly affected by the sun? Hi Michael Perhaps try being more specific in isolating the problem. Is it latency and jitter in the wireless link or past the link out on another network (the internet)? Try the smokeping test to your ISP's network not the internet. Also have you checked you signal and noise levels on the wireless link? (Or asked your ISP to check this) It could be wireless interference from another network. Or it could just be too hot. Ben ________________________________________ From: Michael Davies [mailto:michael(a)hereisasite.co.nz] Sent: Tuesday, 1 August 2006 3:48 p.m. To: nznog(a)list.waikato.ac.nz Subject: [nznog] Wireless link adversly affected by the sun? Hi there, As the subject suggests, I've been noticing an interesting problem with our internet. We're lucky enough to be on the receiving end of a wireless net connection running through Trango broadband hardware, fairly conventional wireless tech. However I've noticed through monitoring the connection with smokeping to various places around the country that the connection quality seems to decrease dramatically through the middle of the day, but not every day. At first I thought that this was simply related to congestion somewhere, but from following the weather a bit I've started noticing that it gets worse on the nice sunny days. For example: Today, a balmy 17 degrees in Dunedin and beautifully sunny all day. Packet loss and jitter begins to increase at about 9am and peaks about 1pm with 60% loss, then at 2pm as if flicking a switch it returns to nearly 0% loss. From looking at the graphs over time, this does happen quite often but not every day and the loss today is definitely the worst I've seen it (but also the warmest/sunniest day we've had in Dunedin for quite a while). Has anyone seen or heard of this happening before? Would there be any way to prevent this - supposing that the sun is the culprit - short of installing a Mr. Burns type sun shield? Regards, Michael

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Re: [nznog] Wireless link adversly affected by the sun?
by Andrew McGhie 31 Jul '06

31 Jul '06

Hi I don't know how relevant it is but the military have known for a while that sun spots (flares) will affect radio trasnmissions. Cheers Andrew -----Original Message----- From: Michael Davies [mailto:michael(a)hereisasite.co.nz] Sent: Tuesday, 1 August 2006 3:48 p.m. To: nznog(a)list.waikato.ac.nz Subject: [nznog] Wireless link adversly affected by the sun? Hi there, As the subject suggests, I've been noticing an interesting problem with our internet. We're lucky enough to be on the receiving end of a wireless net connection running through Trango broadband hardware, fairly conventional wireless tech. However I've noticed through monitoring the connection with smokeping to various places around the country that the connection quality seems to decrease dramatically through the middle of the day, but not every day. At first I thought that this was simply related to congestion somewhere, but from following the weather a bit I've started noticing that it gets worse on the nice sunny days. For example: Today, a balmy 17 degrees in Dunedin and beautifully sunny all day. Packet loss and jitter begins to increase at about 9am and peaks about 1pm with 60% loss, then at 2pm as if flicking a switch it returns to nearly 0% loss. From looking at the graphs over time, this does happen quite often but not every day and the loss today is definitely the worst I've seen it (but also the warmest/sunniest day we've had in Dunedin for quite a while). Has anyone seen or heard of this happening before? Would there be any way to prevent this - supposing that the sun is the culprit - short of installing a Mr. Burns type sun shield? Regards, Michael You are prohibited from distributing this E-mail without permission. If you have received this E-mail by mistake or are not the intended recipient, please notify the sender and erase the message immediately. This E-mail message and any accompanying data is confidential and may be legally privileged. The Nelson City Council does not warrant or guarantee that this communication is free of errors, virus or interference. This e-mail has been scanned and cleared by MailMarshal.

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Re: [nznog] Wireless link adversly affected by the sun?
by Erin Salmon 31 Jul '06

31 Jul '06

What sort of antenna do you have? If your link distance is pushing the limits of your hardware, a tiny amount of thermal expansion could potentially reduce the signal past the operating threshold. Unlikely, but possible. Alternatively, could there be other equipment nearby which becomes more active on sunny days? Some sort of secondary effect? Erin -----Original Message----- From: "Andrew McGhie" <andrew.mcghie(a)ncc.govt.nz> To: "Michael Davies" <michael(a)hereisasite.co.nz>; nznog(a)list.waikato.ac.nz Sent: 1/08/06 4:00 p.m. Subject: Re: [nznog] Wireless link adversly affected by the sun? Hi I don't know how relevant it is but the military have known for a while that sun spots (flares) will affect radio trasnmissions. Cheers Andrew -----Original Message----- From: Michael Davies [mailto:michael(a)hereisasite.co.nz] Sent: Tuesday, 1 August 2006 3:48 p.m. To: nznog(a)list.waikato.ac.nz Subject: [nznog] Wireless link adversly affected by the sun? Hi there, As the subject suggests, I've been noticing an interesting problem with our internet. We're lucky enough to be on the receiving end of a wireless net connection running through Trango broadband hardware, fairly conventional wireless tech. However I've noticed through monitoring the connection with smokeping to various places around the country that the connection quality seems to decrease dramatically through the middle of the day, but not every day. At first I thought that this was simply related to congestion somewhere, but from following the weather a bit I've started noticing that it gets worse on the nice sunny days. For example: Today, a balmy 17 degrees in Dunedin and beautifully sunny all day. Packet loss and jitter begins to increase at about 9am and peaks about 1pm with 60% loss, then at 2pm as if flicking a switch it returns to nearly 0% loss. From looking at the graphs over time, this does happen quite often but not every day and the loss today is definitely the worst I've seen it (but also the warmest/sunniest day we've had in Dunedin for quite a while). Has anyone seen or heard of this happening before? Would there be any way to prevent this - supposing that the sun is the culprit - short of installing a Mr. Burns type sun shield? Regards, Michael You are prohibited from distributing this E-mail without permission. If you have received this E-mail by mistake or are not the intended recipient, please notify the sender and erase the message immediately. This E-mail message and any accompanying data is confidential and may be legally privileged. The Nelson City Council does not warrant or guarantee that this communication is free of errors, virus or interference. This e-mail has been scanned and cleared by MailMarshal. _______________________________________________ NZNOG mailing list NZNOG(a)list.waikato.ac.nz http://list.waikato.ac.nz/mailman/listinfo/nznog

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