Base station beckoning to all nodes over common channel!

Hi All,
I'm working over Routing Protocols for wireless sensor networks. Some protocols mention this, "Base station sends beckon signal to all the nodes which it can reach over a common channel" and they use the Received Signal Strength of beckon signals for further protocol formulation. So, my doubt lies in the initiating step. What does sending over common channel mean? Is it that they assume base station to know exact locations of all the nodes in network and sends them the beckon signal initially? Or is that the base station sends some messages over a common channel (say air medium) and all nodes are assumed to catch at least one of those messages and records the Received Signal Strength for further protocol formulation? Please enlighten me over this!
Thanks in Advance,
Vinodh

Abhinav,
You are correct about NI's WSN nodes but it sounds like Vinodh is talking about wireless protocols in general. A common channel would be a defined part of the RF spectrum such as a wifi channel. Generally the radio hardware/software will be able to report back signal strength (RSSI or LQI). Once that is calculated they can send it back to the gateway and then the gateway can use the information for optimizing the network.
Cheers,
Brian A
R & D Product Support Engineer | WSN/Network DAQ
National Instruments

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Airport Extreme Base Station is being hacked/taken over

I've noticed that someone has been hacking and taking over my Airport Extreme Base Station and changing its name, I use strong passwords and this has happened once before.
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Extreme version 5.7
Airport Utility version 5.6 (560.18)
Comcast cable internet
MacOS 10.7.5

I've noticed that someone has been hacking and taking over my Airport Extreme Base Station and changing its name, I use strong passwords and this has happened once before.
Can anyone "see" my base station? As it's name is different than my network name.
Is there some security hole they have discovered?
Extreme version 5.7
Airport Utility version 5.6 (560.18)
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MacOS 10.7.5

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Yesterday I bought a used 1st generation Time Capsule (TC). I expected that it would operate as a "base station" and replace my Airport Extreme Base Station (AEBS) (in addition to it's primary function of acting as a repository for Time Machine back-ups).
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Thanks in advance,
JimH

The Gen1 TC is not simultaneous dual band.. Your AEBS if later model might be.
Did you power cycle the modem as well?
Did you factory reset the TC?
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I am looking to replace my current router and am considering an Airport Extreme base station. Hoping to get some questions answered...
I currently have several Macs sharing a cable modem connection. There is also a printer (Epson R200) attached through a print server breakout box. All connected computers are able to share the printer, using the GIMP drivers.
My set up is:
Cable Modem->10/100 router->10/100/1000 switch
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The Airport Base Station would replace the router. Ideally, I would like to eliminate the print server box and plug the printer into the print server port on the Base Station.
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- What are the advantage of the Airport Base station over the many other 802.11 b/g routers available?
Thanks,
--Joe

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There is some speed loss but its still really fast. I get a 3.5-3.7 MBits/sec when copying a file from a wired computer to a wireless airport extreme connected computer. Its fast enough unless you copy GB of data.
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To me its the integration of the Airport with the Mac OS; easily configurable (try to get WPA protection on another station...); more secure because it can be setup to accept only Macs; printer sharing works great and it is simply beautiful. On the downside, the price.

Communication errors with airport extreme base station

Please help.
I am able to surf the internet wirelessly on my two macs via my Airport Extreme Base Station. However I am unable to print wirelessly via my new HP printer connected to the USB port on the base station.
More worryingly I am unable to use Airport Admin Utility, Airport Set-Up Assistant or Airport Firmware Updater. Whenever I try to use one of these applications they experience errors communicating with the base station. I wonder if this is related to the printer problem?
I have performed soft and hard resets on the base station in addition to removing the power cord - none have been sucessful.
Can anyone please help me.

I may have a solution. I recently upgraded from an ibook to a macbook pro, and had the apple store "migrate" my files, etc., from one to the other. Got it home, everything's fine, airport conects, no problem. Go to print, can't print, decide to run Airport Setup Assistant to reconfigure (why not ?) and, lo. when it gets to "Network Configuation," I get : "An Error Occured while trying to communicate with this base station." Try all the usual tricks, including hard restart (internet connection is fine throughout), but the set-up assistant couldn't get past that point. Talked to apple support, we ran through all the options. He did suggest wiping the network preferences for airport off the harddrive and starting over, but since I had a good internet connection, I decided to wait.
So here's the thing: I got on Airport Administrative Utitity, clicked "Configure," and then "Network." I know next to zip about advanced options, but I decided to click "Distribute IP Adress" And under "Airport Client Computers" selected "share a single address." I left everything else alone. It reset to to the new options, and then, out of curiosity, I opened up set-up assistant, and TA-DA, I got past the screen I was stuck on, and when the next asked me if I wanted to keep all the same settings, I said yes. I kept selecting "Keep/yes", and then saved or okayed the changes. I then got a message that it would restart base station, I was also configured to print (my printer hp laser 1320 was plugged into the base station for all this), and, yes, it does now print.
I don't know if this is the hard way of doing something that I could have done more easily, and/or if even though I had an internet connection, the base station or the set up was still looking for the ibook. I'm sorry for such a long reply, but wanted to include all the steps I took and the exact situation. Does anyone know if I've endangered my security by checkig the "Distribute IP option ?" This is a home computer. Good Luck and hope this helps someone

Configure TC and Airport Extreme Base Stations with different channels

I had to do some serious workarounds to use the Airport Extreme Base Stations as an access point with the same wireless network name primarily due to channel overlap. I thought I would post my results here since I didnt' find a good article online.
Also, I found the Snow Leopard verison (5.4.2) of the Airport Setup Utility far superior to Lion's Airport Utility (6.x) in terms of advanced setup.
Setup is a 3 flloor house where the 3 wired network locations have wireless overlap. The problem was that the access points would not hand off the wireless signal because the channels for each airport/TC were automatically set to the same channel. In non-apple setups, this is how you force a wireless client to switch access points (since the wireless software on your client/mac/windows can detect which access point is stronger and moves to the alternate channel.
Using apple's "Extend this wireless network" option removes any ability to manually configure wireless channels. I am writing this from memory, so feel free to ask questions and I will track this topic:
Procedure
Setup time capsule as your base station. Do all the setup for your wireless and guest networks. Manually configure the network and change the wireless channel to a specific channel for a/b/g networks (e.g., 3) and n networks (e.g, 167).
Plug your first airport extreme/access point into your wired network. Do not plug it into the "internet" ethernet plug, use one of the 3 ethernet switch locations
Use the airport utility to first configure it to "extend" your wired network.
Then, go in and reconfigure it manually in the airport utility. Choose the option to setup a "new network" and name the network the same as the TC wireless network name, security, etc.
Change the channel from "auto" to a different channel than the TC (e.g., 6 and 137).
Now go to the top tab and click on the "internet" icon
Go to the DHCP tab and change it to "bridge mode." This will tell the AE to not give out IP addresses (the TC will do this for you). If you get an error that the IP ranges conflict, you have not done this
Note that if you have a guest network setup, you will need to set this up on the AE as well.
Now test your airport setup. Take your client (macbook, iOS device) and connect to your network. Move to a spot near the TC and pull up a web page. Keep an eye on the signal strength and beginv moving toward the AE. Refresh the page as you move around. You should at some point see the signal strength increase. Refresh your page again. You should be now connected to to the AE. I have found that Macbooks do a better job than iOS devices because you get an extra signal bar to measure strength, and they have larger antennas which allows you to better measure problems with handoff
Another test you can do is to start backing up on your TC and then test the move. The handoff will truly show you that the TC is handling the process but the AE is relaying to the TC for backup.
If you need to setup another AE, simply follow setups 3-10.
I hope this helps others. I've done this setup 100 times on Linksys devices and although they are cumbersome, they at least allow me to do this setup much more quickly and easily than the apple products.

I had to do some serious workarounds to use the Airport Extreme Base Stations as an access point with the same wireless network name primarily due to channel overlap. I thought I would post my results here since I didnt' find a good article online.
Also, I found the Snow Leopard verison (5.4.2) of the Airport Setup Utility far superior to Lion's Airport Utility (6.x) in terms of advanced setup.
Setup is a 3 flloor house where the 3 wired network locations have wireless overlap. The problem was that the access points would not hand off the wireless signal because the channels for each airport/TC were automatically set to the same channel. In non-apple setups, this is how you force a wireless client to switch access points (since the wireless software on your client/mac/windows can detect which access point is stronger and moves to the alternate channel.
Using apple's "Extend this wireless network" option removes any ability to manually configure wireless channels. I am writing this from memory, so feel free to ask questions and I will track this topic:
Procedure
Setup time capsule as your base station. Do all the setup for your wireless and guest networks. Manually configure the network and change the wireless channel to a specific channel for a/b/g networks (e.g., 3) and n networks (e.g, 167).
Plug your first airport extreme/access point into your wired network. Do not plug it into the "internet" ethernet plug, use one of the 3 ethernet switch locations
Use the airport utility to first configure it to "extend" your wired network.
Then, go in and reconfigure it manually in the airport utility. Choose the option to setup a "new network" and name the network the same as the TC wireless network name, security, etc.
Change the channel from "auto" to a different channel than the TC (e.g., 6 and 137).
Now go to the top tab and click on the "internet" icon
Go to the DHCP tab and change it to "bridge mode." This will tell the AE to not give out IP addresses (the TC will do this for you). If you get an error that the IP ranges conflict, you have not done this
Note that if you have a guest network setup, you will need to set this up on the AE as well.
Now test your airport setup. Take your client (macbook, iOS device) and connect to your network. Move to a spot near the TC and pull up a web page. Keep an eye on the signal strength and beginv moving toward the AE. Refresh the page as you move around. You should at some point see the signal strength increase. Refresh your page again. You should be now connected to to the AE. I have found that Macbooks do a better job than iOS devices because you get an extra signal bar to measure strength, and they have larger antennas which allows you to better measure problems with handoff
Another test you can do is to start backing up on your TC and then test the move. The handoff will truly show you that the TC is handling the process but the AE is relaying to the TC for backup.
If you need to setup another AE, simply follow setups 3-10.
I hope this helps others. I've done this setup 100 times on Linksys devices and although they are cumbersome, they at least allow me to do this setup much more quickly and easily than the apple products.

HT1218 Airport Extreme base station is working, but not visible on network?

My Airport Extreme base station is working: all devices are able to connect to the internet, but Airport Utility shows no connection. Only one computer even shows the device-- greyed out-- saying "Device not Found." The airport utility shows version 6.2; OS X version 10.8.3. How do I update the base station to version 7 if the device can't be found? And how do the devices connect to the internet without "seeing" the device?

Thanks for checking. This model should be visible in AirPort Utility in Mountain Lion.
If you have not already done so, I suggest that you perform a complete power cycle on the entire network as folllows:
Power off every network device....in any order you want
Wait a minute or two
Start the modem first, and let it run a few minutes by itself
Start the AirPort Extreme next, the same way
Continue starting devices one at a time about a minute apart until everything is powered back up
Check the network again using AirPort Utility
You can also temporarily connect an Ethernet cable from your Mac to one of the LAN <-> ports on the AirPort Extreme to see if a connection is established that way.
If still no luck, try another Mac if you one handy. After that, all that I can suggest is that you perform a Factory Default Reset on the AirPort Extreme and configure it again.

Do I need a base station to use AirTunes?

Hi. I'm new to the wireless world, so forgive me.
I have an AirPort Extreme Card pre-installed on my computer, but no base station. I connect to my DSL internet via ethernet cable. Not through a wireless connection.
I purchased the AirPort Express under the impression that I could stream music directly to the APX using my AirPort Extreme Card. The AXP is connected to powered speakers. Nothing is working, and I can't seem to find an answer to the very basic question: Do I need a base station (wireless signal) to make my AirTunes work?

Hello kyllmode. Welcome to the Apple Discussions!
I purchased the AirPort Express under the impression that I could stream music directly to the APX using my AirPort Extreme Card. The AXP is connected to powered speakers. Nothing is working, and I can't seem to find an answer to the very basic question: Do I need a base station (wireless signal) to make my AirTunes work?
The AirPort Express Base Station (AX) is a wireless Internet router. You do not need to purchase another router in order to use the AX to stream iTunes, via AirTunes, to your powered speakers. The default configuration of the AX is pre-set to create a wireless network and is already enabled for AirTunes. You just need to make sure that you connect to the AX's wireless network, using the AirPort Extreme card on your computer when you want to stream audio.
Let's double-check your AX's settings ...
Perform a "factory default" reset of the AX
o (ref: http://docs.info.apple.com/article.html?artnum=108044)
To set up AirTunes on the AX, either connect to the AX's wireless network or temporarily connect your computer directly (using an Ethernet cable) to the Ethernet port of the AX, and then, use the AirPort Admin Utility to check these settings:
AirPort tab
o Base Station Name: <whatever you wish or use the default>
o AirPort Network Name: <whatever you wish or use the default>
o Create a closed network (unchecked)
o Wireless Security: Not enabled
o Channel: Automatic
o Mode: 802.11b/g Compatible
Music tab
o Enable AirTunes on this base station (checked)
o Enable AirTunes over the Ethernet port (optional)
o iTunes Speaker Name: <whatever you wish>
o iTunes Speaker Password (optional)
In iTunes:
iTunes > Preferences... > Advanced > General
o Look for remote speakers connected with AirTunes (checked)

SPA203D Dect 2 - 10 Not picking up SIP credentials from base station

Hi There
Installing 4 x SPA203D Dect handsets tied to the base station SPA232D. All handsets are registered and sync'ing with the base station but the SIP credentials are being populated from the quick setup (Dect 1). Under the Voice menu each Dect has its own SIP credentials but these are not being Sync'd to the handsets.
All firmwares are up to the latest version.
Have I missed something in the setup?

so there is a matrix on the quick setup page if you scroll down. that assigns the DECT line to one or more handsets.
the default is all handsets to dect line 1. so choose handset 1, check dect line 1, handset 2, 2 etc...
click voice --> Dect line 2-10 to configure the proxy/username/password/authID, etc

Having trouble with Airport Base Station

Hello,
I am having a problem with getting a base station configured correctly. I am new with working on Apple networks. Currently, there is a communication problem between one of the base stations and the network. I cannot get an Internet connection. One question that I have is if I reset the base station, does it automaticallly go to a default IP address? I keep seeing a 10.0.1.1 address, but I believe that this address is assigned to another base station that is on another floor of the building.
I have gone into the airport setup manager and have tried to set up the base station from there without having success. Do you have any suggestions on how I can set up this base station to get Internet connection?
I see another base station listed on the server that I did not see before, but I'm not sure if this is the correct base station since it has a different IP address. I'd appreciate any help you could provide on this issue.
Thanks

One question that I have is if I reset the base station, does it automaticallly go to a default IP address? I keep seeing a 10.0.1.1 address, but I believe that this address is assigned to another base station that is on another floor of the building.
Yes, if you perform a reset on the AirPort Extreme Base Station (AEBS), it will default to 10.0.1.1.
I have gone into the airport setup manager and have tried to set up the base station from there without having success. Do you have any suggestions on how I can set up this base station to get Internet connection?
Try connecting directly, using an Ethernet cable, to the AEBS you want to setup.
I see another base station listed on the server that I did not see before, but I'm not sure if this is the correct base station since it has a different IP address. I'd appreciate any help you could provide on this issue.
To set up multiple base stations, you will want to use the AirPort Management Utility, which is part of AirPort Management Tools. But, more importantly, what is the desired network that you are trying to achieve? You can connect additional AEBSs to extend the range of a wireless network, either wirelessly or via Ethernet. When done wirelessly, this is known as Wireless Distribution System (WDS); as wired, it called Roaming.
It sounds like your building has a wired network and that your are using AEBSs at multiple locations throughout the building, but all connected to the building's Ethernet network...correct? This would be a roaming configuration. If this is true, then:
- Each AEBS would have it's LAN port connected to the building's Ethernet ports on the same subnet.
- Each AEBS would have a unique Base Station Name.
- All AEBSs would have the same Network Name and Password.
- Each of the AEBSs would be set up as bridges

Additional Ethernet ports on Airport Extreme Base Station

I would like to know how one could add additional Ethernet ports to an Airport Extreme Base Station - I need 6 ethernet ports.
Is it possible to daisychain two Airport Express Base Stations so that all computers can see each other, or is it best to buy an ethernet switch?
If the latter is the answer, hardware recommendations would be appreciated.
Thanks

Is it possible to daisychain two Airport Express Base Stations so that all computers can see each other, or is it best to buy an ethernet switch?
It would be best (cheapest) to use an Ethernet switch instead of getting a second wireless router with a built-in switch.
If the latter is the answer, hardware recommendations would be appreciated.
A 4-8 port model from any of the name brand vendors should do just fine. An example would be the Linksys SD2008.

Scripting AirPort base station administration

I'm wondering if it is possible to script administering AirPort base stations. I tried looking around & I couldn't find anything specific (though I'm guessing that the answer is no, esp. since AirPort Admin Utility isn't scriptable).
Anyway, here's my problem. The office of a client has set up a collection of AirPort base stations and they all use hardware access controls (ie. MAC address ACLs). That means that whenever a new machine needs to access the wireless network, I need to go into the configuration of each base station (there are 6 of them) & manually add its MAC address to the ACL. Needless to say, it's a pain & it would be so much better to be able to automate it.
Is there any way to do this? It seems like a fairly obvious thing to me... Thanks in advance.
Tim King
[email protected]

istumbler from www.istumbler.net is far more fun, but still not applescriptable.
You can 'System Event' macro it if you are keen, but what you want to do can be done with CE Quickkey for $80us
http://www.cesoft.com/products/qkx.html
With 6 airport you must be rich
good luck

MY BASE STATION VANISHED

i had noticed this morning i had no internet and this afternoon i called time warner and while my ethernet was directly connected to my macbook, the internet came back and everything was great. then i reconnected the cable box to my extreme base station, and the internet vanished. i called time warner who told me my cable box was not sending ip address to base station and they told me to call apple..well apple is closed so i searched for a solution here, and decided to update everything, and then reset my base station. well i have reset the base station twice, and all it is doing is blinking amber, and it is nowhere to be found on my computer. every time i try to select my base station some other persons base station shows up and my computer cant find mine..please help this is an extreme pain in the ***...

Hello kathysong. Welcome to the Apple Discussions!
Try the following, in order, until resolved:
1. If the modem has a reset switch, use it to reset the modem. Wait at least 5-10 minutes for the modem to initialize.
2. Remove power from the modem. If it has a backup battery, remove this as well. Wait 5-10 minutes. Replace the battery, and add power back to the modem.
3. Perform a complete power recycle of your network components as follows:
Modem/Router Power Recycling - Quick
o Power-off the modem, 802.11n AirPort Extreme Base Station (AEBSn), & computer(s); Wait at least 5 minutes.
o Power-on the modem; Wait at least 5 minutes.
o Power-on the AEBSn; Wait at least 5 minutes.
o Power-on the computer(s)
If this fails to get the modem to "recognize" the Internet router, then try the "Full" version.
Modem/Router Power ReCycling - Full
o Power-off the modem, AEBSn, & computer(s). (Wait at least 30 minutes. If possible, leave the modem off overnight.)
o Power-on the modem; Wait at least 15 minutes.
o Power-on the AEBSn; Wait at least 5 minutes.
o Power-on the computer(s)
4. Contact your ISP to have them perform a "modem reset."

Need help with airport base station setup

I have a classroom with a dozen G5 Mac Pros running Tiger and we want to allow them to use a couple of A3 photo-quality inkjet printers and a couple of flatbed scanners.
I see that the airport base station extreme only has one usb port.
Is it possible to use one airport extreme base station to connect all of these peripherals, add airport cards to each Mac Pro, and be able to use any of the printers or scanners from any of the Macs?
What other equipment is necessary?
Should we look to buy any specific printers or scanners that will be more compatible?
Is there some other approach that will work better?
Thanks for any advice.

one usb port but user can connect a multi port usb power hub for multiple devices. I run three Lacie quadras connected to a seven port Belkin hub to the Extreme N router.

HT3728 my broadband speed has all of a sudden been reduced dramatically over the weekend. the isp asked me to eliminate my apple airport express base station to make sure that my 20mb band is being delivered which i did and confirmed so.

MY BROADBAND HAS BEEN REDUCED DRAMATICALLY IN MY HOME NETWORK USING MY AIRPORT EXTREME BASE STATION.
THIS HAPPENED SO UNEXPECTEDLY OVER THE WEEKEND. I CALL MY ISP AND THEY SIMPLY TOLD ME TO ELIMINATE THE AIRPORT
EXTREME BASE STATION TO CONFIRM THAT WHAT I HAVE PURCHASED IS BEING DELIVERED WHICH I DID AND CONFIRMED.
MEANWHILE USING MY NETWORK UNTIL LAST FRIDAY EVERYTHING LOOKED JUST GREAT.
I WONDER WHETHER I WOULD HAVE TO RESET MY AIRPORT EXTREME TO FACTORY SETTINGS TO RECONFIGURE IT.

Hmm. Your ISP is incorrect in telling you that removing any of your routers on the local area network will have anything to do with the bandwidth performance that they provide you at the Internet modem. On the other hand, changing/removing networking equipment on your local network DOES affect bandwidth performance on that local network.
Most likely what the ISP is asking you to do is verify that you are getting their promised download/upload bandwidth at the modem. It appears that you did that and verified that you are getting the stated bandwidth.
So, we should take a look at why, when adding the AirPort Extreme, you are getting less.
First off, which AirPort Extreme model do you have? What is the make & model of the broadband modem that your ISP is providing you?
It is always a good idea to perform a complete power recycle of your networking equipment when introducing new hardware. Please check out the following AirPort User Tip for details.
(p.s. Please don't use all capital letters when you post. It appears to readers that you are shouting. Thx!)

Base station beckoning to all nodes over common channel!

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