MAR bus demo

We worked last night on Porting the code for the MAR bus demo to the WAIL server. A few hurdles were encountered. One of which was getting access to the various components of the server.  Once we are allowed access to view the MySQL tables etc. we faced another hurdle. The LogEntries table has about 25million records. However, once we reconfigured our query to pull only the latest entries, it ran lightning Fast. All we have to do now is make sure that Apache will work with PHP on our demo server. This is currently being resolved and should provide us with the live data that we would like to view on Google Maps!  More on this as soon as we get it up and running....

Benchmark results for MAR (Per Connection)

As of Friday Night (5/2/08), half of the Benchmarking for the current version of MAR was finnished. The Half that was finished, was the Benchmarking TCP Bandwidth. The Server used for ipef was not accepting UDP connections for some reason so that needed to be delayed until later. Now the port is working for UDP as well and the Benchmarking for UDP will be completed Tomorrow afternoon (5/6/08).

The results for TCP benchmarking, as predicted, show that MAR does not effect the overall bandwidth. This makes sense because the bottleneck here is the PPPoE connection.  Further UDP testing will determine our results for Latency, Jitter, and Packet Loss percentage. We expect these will show the crux of our engineering tradeoffs (i.e. we expect poorer performance).  Obviously we would like only slightly poorer, or negligibly poorer,  performance difference.

Vendor Product IDs

The following are used in conjunction with various mobile network adapters

BROADBAND MODEM MODEL	VENDOR ID	PRODUCT ID	FORM FACTOR
NOVATEL MERLIN S620	0x1410	0x1110	PC CARD
NOVATEL MERLIN S720	0x1410	0x1130	PC CARD
NOVATEL OVATION U720	0x1410	0x2110	USB MODEM
NOVATEL MERLIN EX720	0x1410	0x1120	EXPRESS CARD
NOVATEL U727	0x1410	0x4100	USB MODEM
PANTECH PX-500	0x106c	0x3702	PC CARD
SIERRA AC580	0x1199	0x0112	PC CARD
SIERRA AC595	0x1199	0x0019	PC CARD
SIERRA AC595U	0x1199	0x120	USB MODEM
SIERRA AC597E	0x1199	0x0021	EXPRESS CARD

Put Sprint card on Soekris

The Sprint pcmcia card vendor ID and product ID are the following

Vendor ID: 0x1410

Product ID:0x1110

So we now have the Soekris running as its own independent platform (I.e. does not forward on to another agent local to the bus).

Problem Associated with Safari Multicast DNS

The UDP issues found before are due to the fact that Safari uses Multicast DNS to recognize other devices on a network.  We were not able to identify what or why this was causing us so many problems, however, we did realize that by using firefox, we were much more successful and had many less errors than before when surfing the web.

Pyramid on Soekris and Read Only FileSystem

By default the filesystem is read-only. To change it to a writable system we need to run the command remountrw on the command line. This will load the whole filesystem as read write. Since the dnsmasq is already installed now we will have the permissions to edit the config file and the dns and dhcp should work fine. We should also be able to scp to the Soekris and place our executable wherever desired.

Soekris port (Read Only Filesystem)

Right now our biggest issue with porting over to the Soekris machine is that the filesystem installed is Read Only.  The only luck I had with writing to files were those that had symbolic link permissions (i.e. files that had permissions that started with "l").

Without being able to change file permissions we cannot write to any directory that is not a symbolically linked file. These are things I tried, to no avail because of this crux

• apt-get install - doesn't work because it references a log file to check if a certain
• scp 
• tar
• chmod
• chown

Also the OS does not have Make installed. This is also crippling because we need make to install make, and also any other program that uses make.

Here are other things that are not installed

• sudo
• man

needless to say I am really up a creek without a paddle with this thing. However there is good news. dnsmasq is already installed! We can't change its dnsmasq.conf file because of aforementioned permissions problems, but if we can get over that, we are only a hop skip and a jump away from getting this thing up and running.

Here is my suggestion.

We create a new linux image on a different system (one that we can actually write to/read from) with all of the things we need preconfigured. Then we reimage the Soekris box with this custom OS

I didn't have time to look at solutions to the UDP issues, however I did find that Multicast DNS is used by Macs to do service/device discovery. While this does not solve our problems it does help us understand why we were getting these weird UDP errors since we were using my Macbook pro to test MAR

Thats all for now.

-Ryan