Internet Connection Lost

My WinXP Pro notebook uses an SMC2435W wireless card connecting with a Linksys router. I decided to make my network a little more secure by changing the SSID from the default. I also changed the SSID on the notebook. Afterwards, there was no way I could connect to my home network. No other settings were changed. I reset the router with no success. Finally, I disabled WEP on the router and my notebook, and my connection now works properly. I've used WEP for several years. I don't let Windows set up the network connection. I find the available network on the SMC icon on the taskbar and let it connect there. Any idea how changing the SSID could have caused this problem? I've never had any issues with my wireless connection before.

Thanks! Scott

Reply to
Scott
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What did you change the SSID to? length and special characters come to mind, along with using the arrow key instead of the space bar and leaving a hex 00 instead of a space..

Reply to
Peter Pan

You don't change the SSID on the notebook. You use the XP Wireless Zero Config tool or whatever comes with your SMC wireless card to search for available wireless networks. When it finds one, you select the desired network by SSID. That eliminates typo errors and sometimes accomidates garbage accidentally introduced into the SSID name. Your unidentified Linksys router will not allow you to type in garbage into the SSID and is fairly good at limiting the SSID length to 31 characters. However, accidents and bugs do happen and you may have goofed in setting the SSID. Spaces are always a problem so I suggest you avoid those.

Resetting the router should have allowed you to connect with "linksys" as the SSID and no encryption.

OK, I know the problem. Windoze shows a connection but you don't get an IP address and nothing works. The WEP key is confused between ASCII and Hex. Try: Start -> run -> cmd ipconfig If your IP address is 169.254.xxx.xxx, then you didn't get an IP address from the router. Probably because of the WEP key. If it's

192.168.1.xxx, it's working and something else is wrong.

I'll assume Windoze XP. Windoze XP SP2 wireless is really stupid in the way it hides useful diagnostics. It will show a connection, with

5 bars, and your only clue that the WEP key is screwed up is that it says something like "waiting for IP address". Eventually, it proclaims "reduced connectivity". That's Microsofts way of saying the DHCP just failed and you don't have a useable IP address. Yech.

So, dive into your unidentified Linksys router, and reset the SSID using a HEX key instead of an ASCII to Hex converted key. Scribble down the Hex key and insert it in the SMC config file. It has to be either 13 or 26 characters long for 64 or 128 bit WEP respectively. That should work.

Sounds like you're doing it the right way. However, it's difficult to remember what you did years ago. Changing the SSID should have no effect on the WEP key, but will change the saved "profile" used by Windoze. By changing the SSID, you effectively needed to create a new profile. If you didn't remember the way you created the WEP key, then there's no guarantee it will be identical to your previously working setup. Anyway, that's my guess.

Reply to
Jeff Liebermann

Peter Pan,

I had changed it to a simple four-letter word. Anyway, I changed everything back to the default, and the connection works. The big problem now is that with my Charter Pipeline, I get the proper 256kb upload speed, but the download speed is capped at 100kb. It should be around 2.8 mbps.

Any ideas on what to try next?

Thanks! Scott

Reply to
Scott

No. Just about anything can be made to work. If you're looking for more speed, then an 802.11g card should constitute an improvment.

Reply to
Jeff Liebermann

Don't be sorry. It's a good wireless router.

Ping the router continuously: ping -t 192.168.1.1 Any lost packets? Any long delays? Any kind of traffic problems?

The WRT54G is an 802.11g wireless router. Your SMC2435W is 802.11b. There's a setting in there somewhere that allows you to change from: 802.11b and g 802.11g only 802.11b only There's also a setting for the maximum connection speed. Try the

802.11b speed only and see what happens.

Wired computah works, so something must be busted on the laptop. Is there an ethernet port on the laptop? Try it with the ethernet port and see if it works.

If the laptop appears to be unusually slothish, try looking for spyware, viruses, worms, or such. They can slow down the computah.

If you're running Windoze XP, the Windoze Update feature has the bad habit of downloading updates in the background. The machine will appear to be running slow and benchmarks will look like the system is almost comatose. Wait until the update is done or just kill the updates.

Did you change RF channels? You may have landed on one that's occupied by the neighbors endless TIVO downloads. Try a different channel (1, 6, or 11).

Go to:

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see what Tweak Tester II complains about. Your IP stack may be misconfigured.

Reply to
Jeff Liebermann

Jeff,

Sorry, my Linksys router is a WRT54G. I can go through the steps you've outlined. However, I have since reset the SSID to "linksys" and disabled WEP, and I get on the internet now. The new issue is that with my Charter Pipeline connection, I get the normal 256kb upload speed, but the download speed seems capped at 100kb...instead of the 2.8 mbps that it should be. My wired computers are getting 2.8 mbps on the same network. I'm using an SMC 22MB card that's been working perfectly for several years. I reset the settings for this card (Transmission Rate, etc.) to I believe what it was before. Sometimes, when going to

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to check my speed, I get 2.8 mbps, but then when I recheck it a few seconds later, the download speed has dropped to 100 kbps. Also, looking under My Network Places and my wireless connection, under Status it shows 11 mbps. So, where could the bottleneck be?

Thanks! Scott

Jeff Liebermann wrote:

Reply to
Scott

Jeff,m

By the way, I've been thinking of replacing the old SMC notebook card with an up-to-date Linksys wireless card. Is that likely to help?

Scott

Jeff Liebermann wrote:

Reply to
Scott

Jeff,

Here's an update: I have the Transmission Rate on my SMC wireless card set to 11 mbps (as recommended by SMC tech support). I checked on my Linksys router and found the Transmission Rate was set to Auto. I changed it to 11 mbps. Now my download speed swings between 233 kbs and 2.8 mbps...definitely an improvement.

Does it sounds like the SMC notebook card may be causing the problem?

i no longer have any trouble connecting and getting on the internet, although I haven't tried enabling WEP again.

Thanks! Scott

Jeff Liebermann wrote:

Reply to
Scott

I 'm not sorry I have a Linksys router. I agree it's a good router. I was sorry for not specifying my router type for you in the beginning.

When pinging, I get: Time=1ms TTL=64. Is that good?

I tried changing it from 'Mixed" to "B", but it made no difference, so I put it back on Mixed, where it was originally.

I plugged in an ethernet cable, and wired I get 2.9 mbps, so it's not that.

I use AdAware and CounterSpy religiously, and my notebook runs like a cheetah...so I doubt it's spyware.

I do all Windows Updates manually. More control that way.

I switched from channel 6 to channel 1, where I had it originally. It didn't make a difference.

Here's what Tweak Tester showed:

Your Tweakable Settings: Receive Window (RWIN): 17640 Window Scaling: off Path MTU Discovery: ON RFC1323 Window Scaling: OFF RFC1323 Time Stamping: OFF Selective Acks: ON MSS requested: 1260 TTL: unknown TTL remaining: 117

  1. Test 146000 byte download Actual data bytes sent: 146000 Actual data packets: 116 Max packet sent (MTU): 1300 Max packet recd (MTU): 1300 Retransmitted data packets: 0 sacks you sent: 2 pushed data pkts: 15 data transmit time: 4.359 secs our max idletime: 205.1 ms transfer rate: 28083 bytes/sec transfer rate: 224 kbits/sec This is not a speed test! transfer efficiency: 100%

  1. ICMP (ping) check Target unpingable

It looks like something with my SMC wireless card got misconfigured. I can still operate halway decent with speeds ranging from 230 kbps to 2.8 mbps. I may try a Linksys G wireless card. It's bound to work better with the Linksys router.

So, what do you think? Is this one of those mysteries that may never be solved?

Thanks again! Scott

Reply to
Scott

Is 'linksys" the default that everyone else in the world knows about?

Maybe you should implement some kind of wireless security before you get used and abused. ;-)

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That router has logging and you can use a logviewer and you can check the logs in real time and go back in time to see that your network of machines wire or wireless has not be compromised and inbound and outbound traffic is not happening with a dubious remote IP on the WAN or private IP on the LAN, since you most likely have the wireless wide open to attack.

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Duane :)

Reply to
Duane Arnold

It's the only laptop that connects...but I also have an iPqaq 4155 with Wi-Fi, so I assume I'll need to keep the router on "Mixed".

My three wired computers get anywhere from 2.75 mbps (Win95 machine) to 2.96mbps. Each uses a 10/100 network card. Charter Pipeline service is rated at 3 mbps.

I checked Task Monitor, and Processor Usage is averaging 1-2 percent with occasional spikes to 25%.

I used TCP Optimizer, and it found Max Packets Sent to "Empty", so I optimized it to 1500.

Also, I downloaded and ran DrTCP with this result::

TCP Receive Window: 256960 Max Duplicates ACKs: 2 TTL: 64 MTU: 1500

Before tinkering, my laptop would typically get from 2.75 mbps to 2.85 mbps, somewhere in that range...and that was with WEP enabled. Now, WEP is not enabled. I may try that again following your previous instructions.

Are you saying that the wired connection defaults to the lower speed of the wireless connection? I've always found the wired speeds to be in the

2.9mbps range...while wireless is closer to 2.8 mbps.

The reality now is that the wireless speed will show up as 256 kbps upload (very consistent) and the download speed 2.50 - 2.85 mbps. A few seconds later, I check the speed again, and it's 230 kbps download. Checking it right after that, it's back up to 2.5 - 2.85 mbps. Sometimes it's 1.8 mbps.

Any idea what could be causing the wild swings?

If there's something flaky with the TCP/IP stack, how does one fix that? (I've heard about people spending hours rebuilding their stack).

Thanks again! Scott

Reply to
Scott

Clarence,

snipped-for-privacy@XReXX> Scott wrote:

Clarence,

My SMC driver is v3.0.0.1 dated 03/03. I believe I got it from SMC's website.

When I had the problem setting up a new SSID (I typed in a new SSID on the wireless card options under Device Manage-bad idea), I ended up removing the new SSID profile in the SMC utility program on the taskbar, but only when I deisabled WEP did I get my internet connection back. So I'm reluctant to re-enable it, but I suppose it's a logical next step. As I recall, when I first enabled WEP a year ago, there was no problem with a different profile--it just worked, as long as I entered the same key in the router and the laptop.

The only time I touched WEP after that was after occasionally having to reset the router. Then I would re-able WEP and re-enter the key, so I'm sure I know how to type it in properly.

I never got the "connection balloon" that you experienced.

I'm still wondering if replacing the SMC card for a G Linksys card to match my router might get everything working optimally again?

Thanks! Scott

Reply to
Scott

I have an SMC2435W card on WinXP-SP2. I set it up the way I have set up several wireless cards recently on WinXP-SP2. No CDROM or downloaded drivers from the vendor. (The SMC2435W is particularly old, anyway.) A hardwired connection to the internet, plug in the wireless card, let Windows search the web for proper drivers. All is good. For the SMC2435W, this is a Microsoft-provided driver 5.1.2535.0 dated

7/1/2001.

But, your problem isn't the card, it's your new attempt at WEP.

When I first configured WEP, I had to delete the Windows profile that had the SSID of the non-WEP router, or change the SSID so Windows would configure correctly and pop up a WEP key page.

It seems like you did that, but maybe, as Jeff suggested, there was some slip in transcribing the WEP key.

An annoyance that I had with the 2435W was the little "connection" ballon that would pop up telling me that I had just connected. I thought I was connected... It seemed to be working ... It must have been disconnecting just for a moment.

That annoyed me enough that I bought a Netgear WG511 card.

Reply to
dold

Perfect. If the laptop were excessively busy, the time delay would be longer or packets would be lost.

If your SMC card is the only wireless device that connects, you might as well leave it on 802.11b only. Mixed does some fancy switching between "g" and "b". If you experience an excessive delay when using the laptop after a long idle delay, try it on "b" only.

Well, maximum theoretical speed for 802.11b at 11Mbits/sec is about

5.5Mbits/sec. Subtract about 10% for WEP. However, that's under absolutely ideal conditions. You'll get about 3.5Mbits/sec when you're close to the router. Incidentally, don't get too close as there's often a "dead zone" at less than about 2ft from the router.

With a wired connection, you've eliminated anything that has to do with the wireless sections. Both computers get about 2.8Mbits/sec when directly connected with a cable. The 2.5 that your wireless is getting is probably overhead from WEP and encapsulation. I would have expected a bit faster, but that might be all what your 3MBit/sec DSL can deliver.

Check the Task Manager and see if the CPU is excessively busy. You don't need disk activity to busy out the system. I've been fooled by spyware and find it necessary to use MS Anti-Spyware Beta, Ad-Aware SE, and Spybot S&D 1.3. No single tool catches all the spyware.

Good idea. I wished everyone would do that. I had to block access to the update site when a mob of users bearing wireless laptops showed up at a convention and all the laptops simultaneously decided that this would be a great time to update themselves.

OK, so it's not interference.

MTU is a bit small. It should be 1500 for normal ethernet and 1492 for PPPoE. You may wanna download DrTCP and do some tinkering.

OK, no lost packets. Nothing wrong with the laptop. Are you sure it was faster than 2.5Mbits/sec before you started tinkering?

Maybe. However, if your unspecified internet connection is no faster than 3Mbits/sec, then what you're getting is both realistic and about as fast as it will go. A faster connection between your router and the laptop is not going to make downloads go any faster. For example, your wired connection is probably 100mbits/sec. Yet, it's going no faster than the wireless. What you will get is a more reliable wireless connection with 802.11g. OFDM is much better than CCK modulation.

Reply to
Jeff Liebermann

The 2435W is one of the "22MHz" cards, and my new Netgear WGR614v4 "g" router was trying to play "PBCC" with it. I set the SMC2435W to "TX Rate:

11Mbps" and got more stable results. That was with a previous Win2000 laptop and the SMC driver. I forgot all about it when I got the WinXP laptop.

Since I'm using the Microsoft Driver, I don't see that same option. Maybe it's the "4xmode"?

Reply to
dold

Worked for me ;-) My laptop with the WG511 was stolen, so I was back to the SMC card for a while, but I was whining about the connection balloon. My daughter suggested that I should buy a new WG511 and quit whining. So I did.

Reply to
dold

Nope. The Ipaq 4155 is 802.11b, not 802.11g. It's safe to try "802.11b only" setting.

Three computers? Are any of those generating traffic while you're testing the laptop?

That's normal. Nothing is apparently running in the background to slow down the network traffic.

I assume you ran this on the laptop. The huge receive window (RWIN) seems a bit large for 3Mbit/sec cable modem service. Do you typically connect to extremely high latency and slow servers? Methinks you might wanna drop this down to a more reasonable number:

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Sorta. This is in reference to replacing your 802.11b card with an

802.11g card to get better performance. It *MIGHT* happen. Your performance is limited by the speed of your cable modem service, not by the connection speed between your laptop and the router. At this time, your wireless connection seems to be having a bad day and is slowing you down. The maximum thruput of 802.11b is typically about 3.5Mbits/sec which is fairly well matched to the maximum speed of your cable system. If you increase the speed of the wireless part, you are still limited in speed by the cable modem part. As an example, I noted that if your wireless connection magically went at the speed of your wired LAN connection (100Mbits/sec) you would still be limited to 3Mbits/sec by your cable modem.

Can I change my mind? With the maximum wireless thruput being so close to the cable modem speed, it won't take much to convince 802.11b to slow down and constipate the connection. 802.11b at 11Mbits/sec is not terribly stable and your system will tend to go slower. If you switch to 802.11g, the ODFM modulation will have less of a tendency to slow down below about 3Mbits/sec thruput, and therefore will give a more reliable connection. It cannot go faster than 3Mbits/sec overall thruput through the cable modem, but it will probably tend to stay at

3Mbits/sec thruput better than 802.11b. Yeah, I would get an 802.11g card.

Yes. Interference from other stations, microwave ovens, cordless phones, x10 TV cameras, your Ipaq, reflections, and even door bells, can cause the system to slow down through delays or packet loss. Watch the connection speed. If it drops below 11Mbits/sec when you're close to the WRT54G, you may be hearing something. Switching between

802.11g and 802.11b modulation on the access point should have introduced some delays, but apparently you're not seeing any. I sure see them on my hardware.

Drivel: I was having a packet loss problem right on my desk. Wireless data between my BEFW11S4v4 and various client radios would be flakey, apparently from interference. I eventually traced the problem down to a new low voltage incandescent desk lamp. The light bulb runs on 12VDC. There's a small switching power supply in the base that converts 117VAC to 12VDC. Turn it on and it sprews substantial RFI that goes well into the microwave region. Some aluminium foil and a few ferrite beads solved the problem.

Only hours? I used to spend days optimizing the parameters for different conditions. The setup for satellite, wireless, DSL, packet radio, dialup, cellular modems, 1xRTT/EDGE/GPRS, and other forms of connectivity, are not exactly the same. There's no set formula that works for every machine. The IP stack does a good job of adjusting itself to meet the demands of varying connections. However, it's not perfect and can be made to screw up with demanding services such as VPN over satellite, VoIP, and streaming video. It's not just tuning the Windoze IP stack, but also that of the routers and wireless connections.

There are a few things you can tune to improve wireless connectivity such as CTS/RTS flow, and fragmentation threshold. However, these will improve reliability and reduce packet loss at the expense of thruput. Your existing system cannot tolerate much loss in thruput before the wireless link becomes your major bottleneck. Therefore, (changing my mind) I suggest you invest in an 802.11g card, which will give you some performance headroom in which you can make adjustments.

Meanwhile, if you ran the tweak test at DSLReports, it probably offered some recommendations (usually to RWIN and MaxMTU). I would follow those recommendations. If you're really into this, go to:

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other WEB100 server, and do some comparative benchmarking. Be sure to read:
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John Navas on tuning and optimization proceedures and tools.

Reply to
Jeff Liebermann

Jeff,

I tried the B-only setting, but it didn't seem to make a difference.

Typically, the other two computers are not accessing internet at the same time.

I checked the info at dslreports, did a ping test, and refigured the RWIN number at 33375. I plugged it in, but then my max speed slowed to 1.63 mbps. Using TCP Optimizer, I went back to what it recommended (256960), and my max speed jumped back to 2.83 mbps (with occasional swings to 233 kbps, which is the same as what I've been dealing with over the last few days). So, apparently the higher RWIN is best for my system. Is that a clue as to what may be wrong with the rest of my setup?

I've never had problem with interference before. There's no new phones in the house. In my neighborhood, the homes are farther apart. I used to be able to see a neighbor's Netgear wireless connection when on my deck, but it's not there any more.

OK, you've convinced me to try a Linksys G card. It's probably a much better match to my Linksys router. One thing I have noticed is that copying and pasting files from my desktops to the laptop has considerably slower since this problem started. A 14mb file wants to take 15 minutes, instead of 2-3 minutes.

I went back to the tweak test at dslreports.com, and it shows my RWIN at

33375. Funny, TCP Optimizer shows the TCP receive window set at 256960, while DR TCP shows it at 33,375. Something doesn't jive here.

Anyway, I'll probably pick up a Linksys G card. Today, I think I'll try re-enabling WEP, just to be more secure. I'll leave SSID alone for now.

Also, I'm going to check a few local WiFi hotspots to see what kind of speeds I'm getting there...and I'll report back here afterwards.

Thanks for much for all your help! I'm learning a whole lot :)

Scott

Reply to
Scott

Well, actually that's good to know. The way the switching between

802.11g and 802.11b works is the access point normally sits listening for 802.11g clients. Every few seconds, it switches to listending for 802.11b clients, which effectively turns off the receiver to 802.11g reception. If it hears something with 802.11b, it will sit in the 802.11b mode for about 2-3 seconds before going back to listening for 802.11g clients. What I've been assuming (possibly incorrectly) is that 802.11g take priority and that even if associated with an 802.11b client (such as yours), it will regularly switch to 802.11g. Apparently not. If it does, it should have slowed down your connection somewhat. Next time I have a WRT54G on the bench, I'll try to decode how it works.

I had a problem yesterday with a similar performance situation. It turned out that one of the office computahs had Symantec Live Update running, but all the software that it was suppose to update had been uninstalled (in a rather sloppy manner). Every 5 minutes, the Windoze scheduler would duitfully connect to the Symantec ftp server, and download an update to software missing in action. They were fairly large and hogging the bandwidth. Aparently it was like that for about

6 months and nobody complained until I setup some streaming background music from the internet, that would fatally choke when the evil daemon did its downloading. Don't assume your computers aren't doing anything when you're not "accesssing" the internet.

I'll guess that you're doing the testing from the wireless connected laptop. Note that the calculated latency should be tested with large packet pings. Using: ping -l 1472

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I get about 60 msec. I have a 1.5Mbit/sec DSL line. Therefore, my rcommended RWIN is: 60msec * 1500 kbits/sec / 8bits/byte = 11250 Bytes Note the bits to Bytes conversion. This is the minimum receive window. A practical value would be 1.5 times this or about 17000 Bytes.

Your 3Mbit/sec cable modem should have about the same latency, but at twice the speed. Therefore, your target RWIN should be about twice my values.

The only way a large number could result in better download speed is if your latency was horrible. Working backwards, to get a recommended

256000 Byte RWIN value, with a 3Mbit/sec line, you would need to have an overall large packet latency of about 500msec, which is clearly impossible. Such large RWIN sizes are used for long latency satellite links, but not with cable modems.

You didn't supply your latency results, so I can't tell how your "TCP Optimizer" came to its conclusions. There may also have been a bits to Bytes conversion error. The benchmark may have been using the cacheing presented by the larger RWIN to produce unusually large transfer speeds.

Hard to tell from here. I suggest you try the same tests with and without the wireless connection to see if there's anything screwed up in that part of the puzzle. Also, try other online benchmarking tools. I suggest:

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one of the other WEB100 servers.

Oh. I assumed that you were only interested in internet performance, which would normally be limited by the cable modem service. However, traffic within your LAN does not involve the cable modem and will therefore be limited by the wireless connection. Definately go for the faster 802.11g card.

What's the URL for "TCP Optimizer". I wanna see if I can break it (time permitting).

Reminder. You may need to set the WEP key using Hex instead of ASCII.

It's part of "Learn By Destroying(tm)". You don't really understand the technology until it breaks (or you break it).

Reply to
Jeff Liebermann

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