Chillifire Hotspot Router Installation Guide

Version 09.10

This procedure is for Linksys routers WRT54GL, WRT54G, WRT54GS, WRTSL54GS and WRT54G3G

Contents

FirmwareInstallation.....2 Method1LoadChillifirethroughwebinterfaceoftheoriginalLinksysfirmware(NormalMode)..2 Method2LoadChillifirethroughTFTPupload(ExpertMode)...4 RouterRegistration......7 RouterConfiguration.....9 Settingyourtimezone......7 DefineaWalledGarden.....9. Defineyourcustomsplashpage/homepage....9 Changeyourrouterspassword....10 ChangeyourroutersSSID(nameofthehotspottheenduserwillsee)...10 AdddevicestotheWhitelisttobypasshotspotauthentication....11 ChangethewirelesschanneltheHotspotissendingon....11 AssigntheEthernetLANconnectionstoeitherHotspotorFreeAccess...12 Changewirelesstransmissionsettings....12 EstablishQualityofService(QoS)andestablishmaximumthroughputrates...13 ChillifireStatus,AddonsandUpgrades....13 AdditionalConfiguration.....14 ShowActiveHotspotConnections.....14 BackupandReloadSettings,ResettoDefaultSettings....15 UpgradingolderChillifireVersions.....15 RevertbacktoLinksysFirmware.....16 Method1LoadLinksysfirmwarethroughGUI....16 Method2LoadChillifirethroughTFTPupload....16 Appendix:......18 LINUXTFTPClientInstructionsforTFTP....18 MACOSXClientInstructionsforTFTP....19
Chillifire Hotspot Router Installation Guide

FirmwareInstallation

Note: The Chillifire firmware will only work on older models of Linksys router WRT54G versions 1-4, WRT54GS versions 1-4. It will NOT work on newer models of these routers.
Method1LoadChillifirethroughwebinterfaceoftheoriginalLinksysfirmware(NormalMode)
Before proceeding with the installation, download the latest software version for the install
http://forums.chillifire.net/viewforum.php?f=38.Toseegetanoverviewofallcurrentlysupportedrouterspleasegoto http://www.chillifire.net/downloads.php.
Not: the required file differs in this method depending on the model: chillifire-wrt54g-squashfs.bin for Linksys WRT54GL and WRT54G version 1-4 chillifire-wrt54gs-squashfs.bin for Linksys WRT54GS version 1-3 chillifire-wrt54gs_4-squashfs.bin for Linksys WRT54GS version 4 chillifire-wrt54slgs-squashfs.bin for Linksys WRTSL54GS chillifire-wrt54g3g-squashfs.bin for Linksys WRT54G3G chillifire-wrt54g3g-em-squashfs.bin for Linksys WRT54G3G-EM Note: We assume for this tutorial that the router you use brand new out of the box. If it is not, we recommend you first reload the Linksys firmware and reset it to Factory Settings before you proceed. Once you have successfully downloaded the Chillifire firmware, remove the sticker on the back of the router. Do NOT run the software on the DVD as requested on the sticker. Instead connect the router to the internet (via your ADSL modem or other internet connection) and your computer through the port marked 1 at the back f the router as shown in the diagram. Once these two connections are successfully made, connect the router to its power source. You will see the LCD labeled Power on the front of the router flashing. Once this light has stopped flashing you can open your favorite browser on your computer. Type in the address http://192.168.1.1 into the address bar of your browser and press Enter. You will now see a pop-up window. Enter admin as user name and again admin as password and press the OK button. Press the Administration tab, and then the Firmware Upgrade tab. On the Firmware Upgrade tab press the Browse button and locate the Chillifire software you had previously downloaded onto the laptop. Press the Upgrade button.
Please note the warning on the screen which says Upgrade must NOT be interrupted. Failure to comply may result in your router becoming unusable. Wait until the Upgrade was successful screen shows AND the LCD labeled Power has stopped flashing AND the LCD labeled DMZ is off, (this may take up to 10 minutes). To be sure un-plug and re-plug the LAN cable connecting your computer and the router. Close the browser and open a new browser window. Type in the address http://192.168.12.1 into the address bar of your browser and press Enter. You will be presented with another logon screen. Enter root as user and shae-4 as password. (You can change the password later to anything you like.)
You will see the initial System Info screen, giving you details about version and status of the firmware. You were Successful!
Chillifire Hotspot Router Installation Guide Method2LoadChillifirethroughTFTPupload(ExpertMode)
This method is safer in many ways and also the preferred method for upgrades. Windows XP/Vista TFTP Client Instructions Steps one and two (download and connections) are the same as in method 1 above. Make sure your router is not connected to the power supply when you start. Windows Vista does not come with the TFTP client installed/activated in standard. Check that TFTP client is activated by going Control Panel -> Programs and Features -> Turn Windows Features On or Off -> Make sure TFTP Client is clicked, Presss OK

Set your computers IP address to static IP 192.168.1.22. Obtain IP address automatically MUST be switched off!
Open two command windows (XP: Start-Run-Enter "cmd", Vista: Start-All Programs-AccessoriesCommand Prompt) In one window, type ping -t -w 10 192.168.1.1 and press enter. 192.168.1.1 is the router IP. Ping will continuously try to contact the router with 10 ms timeout instead of default 4000 ms. In the ping window it will start saying Request Timed out, Destination host unreachable or Hardware error or General failure. Keep this running In the other window, go to the directory in which the downloaded firmware is located. In this example this is D:\Download. The command is D: to move to the D: hard drive and cd \Downloads to go to the Downloads directory. Now prepare the tftp command: tftp -i 192.168.1.1 PUT chillifirewrt54g-squashfs.bin Do not press enter yet! Now plug in the routers power supply (unplug it first for 10 seconds if it was plugged in). Return to the tftp window. As soon as the ping window shows a successful reply (something like Reply from 192.168.1.1: 32 bytes, time=2ms TTL=100), press enter in the window with the tftp command. The image should now be flashed onto the router. If the transfer was successful, the system will let you know. The transfer takes between 7 and 20 seconds. Allow the router to do its thing. It will process the new image, reboot and configure itself. This will easily take 5-10 minutes. Now set your computer back to receiving an IP address through DHCP again (setting Obtain IP address automatically)
Close the browser and open a new browser window. Type in the address http://192.168.12.1 into the address bar of your browser and press Enter. You will be presented with another logon screen. Enter root as user and shae-4 as password. (You can change the password later to anything you like.)

RouterRegistration

Please note: For the registration process to work your router MUST be connected to the internet and have a valid connection. If you cannot access the internet from the computer connected to the router, you are most likely not connected to the internet and this registration process will fail.

Settingyourtimezone

Log in to your router with your username and password. Please select the timezone that is relevant for you or the one closest to you. Selecting the timezone will automatically reschedule the daily reboot to between 3-4am of your local time. It will also determine the most appropriate Chillifire server to connect to so that your users have the fastest possible online connection facility. Press the Save and Apply button.

LinkyourroutertoyourChillifireaccount
On the menu move your mouse over Chillifire, then press Router Registration. You now need to press the Register Router button.
2. Next you will see the Chillifire login screen. If you already have an account created on our website or you are adding another router to your existing account, please type in your account name and password and press the Login button. If you do not have an account yet, please press the Signup Now button and create a new account (see step 3).
3. (Only if you had not yet created a Chillifire account) If you pressed the Sign up now button, you will the Chillifire Control Panel Login screen. Choose an account name (up to 10 characters), enter the billing address details of your account (can be different to the physical address of the router(s), choose the default currency for your router(s) and finally, enter an affiliate code, if you have been given one (otherwise, leave empty). Press the Register button on the screen and you will see a success message.
4. The system will direct you automatically to a screen that allows you to register the router against your account (regardless whether you pressed the Login or the Sign up now button in step 3. IMPORTANT: If you just Signed Up Now as described in step 8 be sure you activate your account first via the activation email you will receive. You cannot logon before you activated the account!
Enter the router location and press Insert.
The system will return a message to confirm the successful registration of the router.

RouterConfiguration

This section describes how to change some configuration settings of the Chillifire Hotspot. While this list of configuration options is by no means exhaustive, it gives guidance to the most popular configuration options. All the configuration options described in this guide occur on the router. Please open your favorite browser, type http://192.168.12.1 into the browsers address bar and press enter. You will need to log in with your user name admin and the password. The standard password is shae-4.

DefineaWalledGarden

A walled garden is a facility that allows hotspot users access to selected sites without having to be logged on. This makes sense if you want to give access to your own website, i.e. your hotels or cafs information pages. The sites the users are allowed to have access to can be defined by entering them into the allowed sites filed and pressing the green button next to the entry field. You can remove allowed sites by pressing the red removal button next to the allowed site. On the Pages tab you can allow complete websites like, say, www.google.com. On the domains tab you can allow entire domains like.google.com (including www.google.com, maps.google.com, mail.google.com etc.) Press the Save and Apply button.

Defineyourcustomsplashpage/homepage
In standard mode the Chillifire system will bring up a login page for users who have connected to the hotspot, open a browser, but are not yet logged in. However, this behavior can be changed with the Custom Splash Page setting. Go to Chillifire->Custom Splash Page Enter your home page with the leading protocol http:// or https:// for example http://www.yourdomain.com/yourstartpage.html or https://www.yourdomain.com/yourstartpage.html You MUST include a link
https://192.168.182.1:3990/prelogin into your home page. This link leads to the Login Page (if the user is connected to the hotspot network) so the hotspot user can buy tickets and can login. Press the Save & Apply button
Changeyourrouterspassword
Go to System->Admin Password The system will prompt you to enter a new password (twice identical) for the user root. Press Subimt to save and continue.
ChangeyourroutersSSID(nameofthehotspottheenduserwillsee)
Go to Network->Wireless Change the SSID to any value you like. Allowed characters are large and small letters [AZ], [az], [numbers [19], underscores and dashes [_-]. Please do use not any other characters and spaces, as this can cause issues. We recommend leaving all other settings as is, unless you really know what you are doing. To change channels, please see point 2 below. Press the Save button
AdddevicestotheWhitelisttobypasshotspotauthentication
Devices that have been put on the whitelist will bypass the login procedure completely and have straight and unlimited access to the internet. The devices that are on the whitelist are defined by their MAC Address, which can be entered on the Chillifire Configuration Screen. Note: The MAC address of a device (laptop etc.) can be found on the bottom of the Chillifire login screen. Just enter the MAC address in the field and press the green add button. Confirm your settings by pressing Save &Apply. To remove a device press the red remove button next to it and press Save & Apply.
ChangethewirelesschanneltheHotspotissendingon
In an area with a number of wireless networks present it can be beneficial not to allow the router to select a channel by itself, but to look for other networks present in the area, and to select a channel that is not yet used. This will avoid interference and improve signal range and clarity for the receiving clients. In a wireless extender scenario, sending and receiving on the same channels between routers is essential. Go to Network->Wifi Press the Scan button After scanning the environment for other networks the system will give you all the other networks it found and their channels. You can now select a channel that is not yet used in your specific environment. Press the Save button To set more sophisticated Wifi settings refer to Change wireless transmission settings below.

AssigntheEthernetLANconnectionstoeitherHotspotorFreeAccess
Go to the Administration section. Go to Network->Switch You can now assign the 4 LAN ports at the back of the router either to free internet access (VLAN0) or to Hotspot controlled paid internet access (VLAN2). The standard configuration has the inner two ports 2 and 3 assigned to the Hotspot, while ports 1 and 4 are guaranteed free internet access. We strongly recommend granting always free internet access to at least one port, preferably port 1, in case more significant repairs are required.
Please observer the following rules, or you may break either specific ports or even the entire Hotspot configuration. The Internet port must always be assigned to VLAN1 Do not assign ports 1 through to 4 to VLAN1 All VLANs must have port 5 assigned VLAN eth0.0 must have a star against it. Violating any of these rules may cause the router to stop functioning. Press the Save Settings button and confirm your settings by pressing Save & Apply We recommend you reboot your router and also unplug the connected devices for at least 10 seconds before plugging them in again. This will enforce that the lease for a new IP address is enforced and that the tunnel for the chillispot connection is built up. We recommend you reboot your router.
Changewirelesstransmissionsettings
Go to the Administration portal to Network->Wifi>Wl0. There you can set transmission power and other transmission and antenna settings. The settings will depend on the routers capabilities and drivers. Recommended standard transmission power is 20dB equating to 100mW. Please take local health and transmission regulations into account when setting this value. Press the Save & Apply button
Chillifire Hotspot Router Installation Guide EstablishQualityofService(QoS)andestablishmaximumthroughputrates
Go to Network->QoS You can set Q0S to 'Enabled' at the top of the Options section. Once that is done you have the option to set a maximum WAN upload and download speed. This will limit the speed for any connection regardless of settings you may choose as part of the Hotspot package setup. We do not recommend you manipulate the QoS firewall settings unless you have a thorough understanding of IP networking. The standard is configured to favor basic services like DNS traffic and SSH, treat web traffic as Normal use, and treat P2P and other data intensive services as least priority.

Press the Save Settings button and confirm your settings by pressing Apply Settings
ChillifireStatus,AddonsandUpgrades
Click on Chillifire Here you can see the status of the Chillifire Hotspot, Restart your remote connection, force the upgrade of your router, and install additional modules. The list of add-on modules will be extended over time as requested by our client base.
Chillifire Hotspot Router Installation Guide SwitchConfiguartion
The Asus routers have a switch tha can be configured via OpenWrt a switch allows you to split the four different LAN ports into different virtual LANs (VLANs). This is useful if you want to have some LAN ports to be controlled by the Chillifire Hotspot, while others have free access to the internet. Go to the Administration section. Got to Network>Switch Ethx.0 are the free ports (ports 1 and 4 in this example). Ethx.1 is the internet connection (the WAN). Ethx.2 are the Hotspot controlled ports (ports 2 and 3 in this example). As you can see the ports 1-4 are numerate 0 through to 3 on this router model.
Important: Never delete the 5, the * sign from the entries it will kill your routers switch and may stop your router from operating as expected. Note: We also recommend you always leave at least one LAN port uncontrolled in case you need to access your router through a LAN cable.

AdditionalConfiguration

Go to the Administration section. Got to Chillifire>Additional Configuration Here you can set the default Idle Time-out period (the period of time an inactive user session on the hotspot is ended by the router) defined in seconds. The default is set to 2600 seconds which is one hour. Clicking the anonymous button will disable the Chillifire logon during logon. The Time of daily reboot define when during the day (in local time) the daily reboot is performed. Default is 4am in the morning.
ShowActiveHotspotConnections
Got to Chillifire->Connections The system shows active usr connections and connected WDS routers. If users are logged in, there will be a Disconnect link at the right hand side of the screen next to the logged in user. This button can be used to force a disconnection.
BackupandReloadSettings,ResettoDefaultSettings

Go to System -> Backup / Restore Here you can save your current settings, reload old ones or reset to default settings of the Chillifire Firmware by clicking the appropriate link and following instructions.
UpgradingolderChillifireVersions
First reboot your router. Wait for the router to be up and log in Go to System -> Flash Firmware Make sure you untick Keep configuration files, Choose the firmware file that needs to be stored on your computer and press Upload image. It must be a firmware file ending with file extension.trx Note: In older version the path might be System -> Upgrade. There may also be a filed Erase JFFS partition which needs to be clicked. The system will present you with an information screen and ask you to confirm that you wish t proceed. Press the Proceed button. You then get update on the progress like so: Once the router rebooted you can close the browser, open a fresh browser window and reconnect to your router to login.
RevertbacktoLinksysFirmware
Method1LoadLinksysfirmwarethroughGUI
Go to the Linksys support site and download the appropriate firmware for your router and region. Download the DD-WRT mini image from the DDWRT website; at time of writing from http://www.dd-wrt.com/ddwrtv2/downloads/v24sp1/Consumer/Linksys/WRT54GL_1.1/ddwrt.v24_mini_generic.bin. Go to System->Upgrade, tick Do not save configuration, select the DD-WRT firmweare file ddwrt.v24_mini_generic.bin and press Upgrade. Wait The system will reboot. Once finished, power down the router and power it up again. Enter 192.168.1.1 into the address bar of your browser and press Enter. You should the DD-WRT firmware loading. Click Administration. The system will ask you for a username and password. Enter user root and password admin (both without opening and closing quotes). In the field Select file to upgrade the original Linksys firmware you downloaded. Press the Upgrade button. The system will upgrade to the Linksys software and the next thing you will see is the Linksys firmware. Done!
Method2LoadChillifirethroughTFTPupload
You can upload the firmware in one step with tftp. Just download the original Linksys firmware you want to revert to and set your PC/Laptop to a ststic IP address and netmask of 192.168.1.22 and 255.255.255.0. Connect the router to the computer via network cable. Open two command windows (XP: Start-Run-Enter "cmd", Vista: Start-All Programs-AccessoriesCommand Prompt). In one window, type ping -t -w 10 192.168.1.1 and press enter. 192.168.1.1 is the router IP. Ping will continuously try to contact the router with 10 ms timeout instead of default 4000 ms. In the ping window it will start saying Request Timed out, Destination host unreachable or Hardware error or General failure. Keep this running

In the other window, prepare the tftp command: tftp -i 192.168.1.1 PUT <name_of_the Linksys_firmware_file> Do not press enter yet! Now you can plug in the router (unplug it first if it was plugged in). Return to the tftp window. As soon as the ping window shows a successful reply (something like Reply from 192.168.1.1: 32 bytes, time=2ms TTL=100), press enter in the tftp window. The image should now be flashed without multiple tries. If the transfer was successful, the system will let you know. The transfer takes between 7 and 20 seconds.

Appendix:

LINUXTFTPClientInstructionsforTFTP

(Thanks to OpenWRT WIKI)

First you need to make sure that you can reach the router on your network, and that it can reach you. If you are using an existing machine which is not on 192.168.1.x, you can temporarily add an interface alias (on most modern Linux distributions). Presuming that the correct network interface is eth0 (if you don't know, assume that it's eth0), run this as root: ifconfig eth0:1 192.168.1.5 netmask 255.255.255.0 When you're done configuring the router, run this (as root again) to take the alias down ifconfig eth0:1 down netkit's tftp commands: tftp 192.168.1.1 binary rexmt 1 timeout 60 trace Packet tracing on. tftp> put chillifire-09.07-wrt54gl-squashfs.bin Or, for a single command, so you don't have to retype each time: echo -e "binary\nrexmt 1\ntimeout 60\ntrace\nput chillifire-09.07-wrt54gl-squashfs.bin \n" | tftp 192.168.1.1 Setting "rexmt 1" will cause the tftp client to constantly retry to send the file to the given address. As advised above, plug in your box after typing the commands, and as soon as the bootloader starts to listen, your client will successfully connect and send the firmware. You can try to run "ping -f 192.168.1.1" (as 1 root) in a separate window and enter the line "put chillifire-09.07-wrt54gl-squashfs.bin" as the colons stop running over your terminal when you power-recycle your router. If you get an ACK from your router but don't send any data, try a different tftp client. atftp works well. This occurs with some netkit tftp packages. ATFTP (Advanced TFTP) commands: atftp connect 192.168.1.1 mode octet trace timeout 1 put chillifire-09.07-wrt54gl-squashfs.bin
Replace chillifire-09.07-wrt54gl-squashfs.bin with the correct file for your Asustek router model

Or use the command-line:

atftp --trace --option "timeout 1" --option "mode octet" --put --local-file chillifire09.07-wrt54gl-squashfs.bin 192.168.1.1 (atftp source code: http://downloads.openwrt.org/sources/atftp-0.7.tar.gz)
MACOSXClientInstructionsforTFTP
(Thanks to OpenWRT WIKI) On Mac OS X, you should be able to flash the router with the command line tftp client, which behaves identically to netkit's tftp above. Some people have had problems with the command line tftp client, however, and recommend using MacTFTP instead:

Download, install, and open MacTFTP Choose Send Address: 192.168.1.1 Choose the chillifire-09.07-wrt54gl-squashfs.bin Click on start while applying power to the WRT54G
Many Macs will disable the Ethernet card when the router is powered off and will take too long to reenable the card, causing the TFTP transfer to fail with an "Invalid Password" error. Many people have had success if they manually configure their network card (in the "Ethernet" tab of "Built-in Ethernet" in System Preferences' Network panel) to:
Configure: Manual (Advanced) Speed: 10 BaseT/UTP Duplex: full-duplex

Roomba MADNeT:

a Mobile Ad-hoc Delay Tolerant Network Testbed
Joshua Reicha reich@cs.columbia.edu
Vishal Misraa Dan Rubensteinb misra@cs.columbia.edu danr@cs.columbia.edu a CS / b EE Department, Columbia University, New York, NY, USA

Introduction

We have built a mobile, ad-hoc, delay tolerant, network testbed (MADNeT). Our testbed is geared towards enabling the exploration of highly disconnected networks whose nodes must store and forward information (multi-hop paths are very unlikely), while allowing us to explore connected network scenarios as well. Using our MADNeT, we can emulate a wide range of mobile networking scenarios and execute real-world (albeit somewhat simplied) data collection missions. Our system is built from commercial off-the-shelf (COTS) hardware running a paired-down Linux OS, yielding a relatively inexpensive but fairly exible mobile network testbed. We have implemented replication-based information diffusion protocols and a distributed opportunistic surveillance application on the testbed as proof-of-concept. Currently, we are rening our software tool-set and instrumenting our nodes to test both our protocols and application.
Figure 1: a single MADNeT node both hardware and software, that would provide as much basic functionality as possible. Consequently, it seemed the most economical way to achieve our goal would be to use COTS hardware and open-source software. Specically, we needed a mobility platform capable of robust movement over indoor (e.g., oor, carpet) and outdoor (e.g., cobblestone, grass) terrain. We also needed a processing platform capable of allowing us to program in a high-level language and make use of already developed libraries for image processing and the like. An equally important issue was that this unit could be interfaced with a standardized commercially available hardware such as wireless radio, web-cam, GPS, USB memory and Bluetooth adapters.

Testbed Design

As we began to explore various mobile networking scenarios, it became clear to us that being able to test our protocols and applications in hardware would bring signicant value to our research. Not only would implementation in hardware provide strong evidence that our techniques could be applied in realworld environments, but the process of implementation and evaluation might also help us rene our assumptions as to what a reasonable semi-autonomous mobile wireless node could do, along with potentially highlighting new directions for exploration. MADNeT was motivated by our need for a system whose nodes could be exibly recongured in both hardware and software, while allowing (although not enforcing) the use of standard wireless protocol families such as 802.11 - at a price point that was relatively affordable (see Figure 2 for sample list of parts and prices). Given that the thrust of our research is in networks, not mobile robotics, vision, or hardware design - we wanted to build our system out of building blocks,

II.A. Hardware

After examining several potential setups, we determined that the combination of a iRobot Roomba Create mobility / sensing platform with a Linksys WRTSL54GS wireless router running OpenWrt (an open-source Linux distribution for embedded devices), along the lines outlined in [6], would provide the ideal balance between capability, cost, and (relative) ease of development. The iRobot Create provided us with a fully functioning mobility platform with the bonus of including on board sensors and actuators. Access to these was easily available through
the iRobot Open Interface [4]. The WRTSL54GS router complemented the Create nicely, providing an integrated unit featuring a Broadcom 4704 processor running at 266MHz, 8MB ash, 32MB RAM, an integrated Broadcom wireless 802.11 radio (unfortunately, the proprietary Broadcom driver provided with OpenWrt limits access to much link-layer information), BCM5325 switch, and a USB 2.0 port. At the time of implementation the WRTSL54GS was the router most fully supported by OpenWrt (support has declined somewhat in the newer Kamikaze branch of the distribution) [1]. With minor modication to the 7-pin DIN to 9pin Serial cable included with the Create, we were able to tap directly into the Creates on-board battery which provides 2700 mAh at 15V. Consequently we were able to power the entire system (router, Roomba, and peripherals) from the Creates battery. While one could obtain increased runtime by mounting a separate battery to power the router and peripherals, powering everything off the Creates battery has the significant advantage of enabling a more highly-integrated system. The entire unit can be turned on and off with the press of a single button and charged with little effort. In fact the unit can be programmed to automatically nd a nearby docking station and charge itself when low on battery (the Open Interface a command which will initiate the Creates built-in nd-dock-andcharge routine). We found that our applications drew from 1000-2000 mAh on the average, although on standby the system could run on far less in 300-400 mAh range. On a full charge the entire system ran between 1 and 2.5 hours, dependent on the application, and hardware conguration. For those who need more power, it is possible to custom-build replacement batteries that hold in excess of 3300 mAh [5].

Part iRobot Create Programmable Robot* iRobot APS Battery iRobot APS Charger Linksys WRTSL54GS Creative Labs WebCam Instant*** OEM USB Hub OEM USB Flash Drive Generic USB-to-serial adaptor 9V Battery Snap Connector Radio Shack #207-325 Power Plug, standard barrel Radio Shack #274-1569 Double-side Velcro Total
* prices reective of University vendors, all sums in USD
Cost* $115! $40 $40 $100 $23 $6 $14 $12 $2 $1 $10 $365
* 7-pin DIN to 9-pin Serial cable & 12AA Battery Case, included
iRobot offers an educators 10-pack for $1000
** for the various compatible web-cam / driver combinations see [3]
Figure 2: part list for MADNeT nodes write fairly sophisticated applications as we will see in III.B. The basic development process consists of implementing the code on a development machine. This code is then cross-complied and packaged using the OpenWrt SDK. The complied packages are then copied to the Linksys unit where they are installed with the ipkg system [2]. This can result in a somewhat tedious debugging process, prompting us make liberal use of optionally compiled debug messages.
III. Utilizing the Testbed
To demonstrate the functionality of our testbed, we have developed a prototype application for distributed opportunistic surveillance in a mobile Delay Tolerant Network (DTN) environment. The goal of our application is to collect data on subjects of interest through the use of passively mobile nodes (nodes which while moving, are not in control of their own movement). In such a setting, nodes can only communicate with peers as opportunity allows. As a concrete example: consider a mobile DTN comprising service robots, vehicles with mounted nodes, and perhaps devices carried by rangers and visitors spread across the expanse of a national park (we have emulated the key ingredients of this scenario using MADNeT nodes opportunistically surveilling a red Roomba). Researchers wishing to collect data on animal populations could task these nodes to opportunistically record relevant data and images when recognized (within a sufcient degree of probability). The question then becomes

Software

We are currently using the WhiteRussian 0.9 build of OpenWrt Linux. Along with the basic functionality native to the Linux kernel, OpenWrt features a functional web-server, rewall, ssh server/client, and most of the basic tools one would expect. An extensive and growing collection of ported packages is easily installable through the ipkg package management system. While micro versions of several programming languages are available, by far the most robust method for programming is to cross-compile C or C++ programs. In WhiteRussian this process is somewhat more difcult than necessary (only certain LINUX/UNIX systems will be able to execute cross-compilation) and certain libraries are unavailable, but overall one can

III.B. Implementation

To implement this application we wrote a robust multi-threaded, socket-based peer detection and message replication engine. This engine worked with data produced by our image recognition routines. For this purpose, we developed a fairly basic image processing engine (detecting our proxy subject, a red Roomba). We have also adapted code provided through [6] to perform I/O operations on the Create platform (in this application used primarily to monitor power readings) and we additionally developed a logging facility which wrote logs to attached USB memory. Figure 3: virtual tree for a single message

IV. Future Work

how to pass this data around the network so as to make it available to the interested parties. We are currently in the process of instrumenting and extending our software with the goal of collecting data on the performance of both our counter-based replication protocol and our opportunistic surveillance application, along with potential extensions of our counter technique to network coding. We also have several exciting applications we are considering developing on our testbed, including techniques for maintaining network connectivity by controlled or partially controlled mobility, and transitioning network topologies between delay-tolerant / high-disconnected and connected regimes. Finally, we are looking into interfacing additional hardware including GPS, digital compass, and RFID card readers.

III.A.

Balanced Replication
To make this information available, we used a novel technique for balanced replication using distributed counter values. This technique for balanced replication works to spread data produced by nodes evenly throughout the network. By spreading data evenly, our system both helps to minimize the average time a data item takes to reach an information gatherer and also increase the robustness of the system to failure of a subset of its nodes. In our protocol when two nodes meet they exchange meta-data, comparing their message caches. Each message in the cache is marked with a counter value. After deciding which messages should be replicated (we need to be selective since our nodes only have limited memory and may be bounded in the time they have to exchange replicas as well) the nodes replicate each others chosen messages and increment the counter value on both the initial copy of the message and replica. The counter values possessed by replicas of a given message can be envisioned as forming the leaves of a virtual binary tree spread throughout the network (Figure 3) with one tree per unique message. By encouraging even growth of the branches through selective replication of lower counter values, we can ensure an asymptotic balance in the number of copies of each message stored throughout the network (under certain random mobility assumptions). Consequently, within a moderate number of nodal contacts, an information gatherer will be able to draw a large portion of the relevant data from our mobile DTN.

V. Acknowledgments

We acknowledge Arpan Saurabh Soparkar for help with the equipment and Matt Yu-Ming Chang for help with the image processing code.

References

[1] http://openwrt.org/,September 2007. [2] http://wiki.openwrt.org/buildroot,October 2007. [3] http://wiki.openwrt.org/webcam,October 2007. [4] http://www.irobot.com/sp.cfm?pageid=248, October 2007. [5] http://www.roombareview.com/hack/battery.shtml, October 2007. [6] T. E. Kurt. Hacking Roomba. Wiley, 2007.