Web based LBS

Evo

Hi

Iam trying to build a web based lbs system... are there any good resources on how to build them ?

philologos

whats an LBS system please (just so i can learn a bit more)

Rew

Locatio Based Service?

I'v done alot of work in the area, what do you want to know?

Evo

Rew wrote:

Locatio Based Service?

I'v done alot of work in the area, what do you want to know?

Well Andrew,

I have a debian web server with Apache, PHP, MySQL.
I have a few wireless AP's.

So if I have a notebook say connected to one of the AP's, how could I associate certain stuff, like buildings or services in a building to an AP and let the user know that those buildings / services are in there?

I could make a table(s) in the DB and match AP ESSID's to certain stuff like a library or shop etc, but is that all LBS is? Is it possible to track a users position in relation to the AP's? How can this be done through the browser ?

thanks

-col

Rew

Evo wrote:

Well Andrew,

Do I know you?

I have a debian web server with Apache, PHP, MySQL.
I have a few wireless AP's.

So if I have a notebook say connected to one of the AP's, how could I associate certain stuff, like buildings or services in a building to an AP and let the user know that those buildings / services are in there?

I could make a table(s) in the DB and match AP ESSID's to certain stuff like a library or shop etc, but is that all LBS is? Is it possible to track a users position in relation to the AP's? How can this be done through the browser ?

You have 2 options:
Server Side
Client Side

Server side:
You poll the AP for the list of devices that are assoicated to it. A decent AP has this via SNMP but you may have to write a screen scraping program to login and pull the details from the HTML.

Client Side:
Write a program that checks what AP is the current one and report it back to your server. Quite tricky. Look at placelab.org and hearcast (might be gone).

I prefer to do it serverside so that any wireless device that associates is supported but that depends allot on your AP's.

After that it is pretty much a cleverly designed DB. Look at the geospatial support in MySQL and Postgres. My memmory is that postgres has support and MySQL doesn't.

Maps are a problem. Google maps is as good as it gets for free. MS have a MapPoint web service which is very good but not free.

You may also want to look at LDAP instead of a DB.

Evo

Rew wrote:

Do I know you?

Yup, sat in the desk behind you for 3 months during the summer

You have 2 options:
Server Side
Client Side

Server side:
You poll the AP for the list of devices that are assoicated to it. A decent AP has this via SNMP but you may have to write a screen scraping program to login and pull the details from the HTML.

Client Side:
Write a program that checks what AP is the current one and report it back to your server. Quite tricky. Look at placelab.org and hearcast (might be gone).

I prefer to do it serverside so that any wireless device that associates is supported but that depends allot on your AP's.

After that it is pretty much a cleverly designed DB. Look at the geospatial support in MySQL and Postgres. My memmory is that postgres has support and MySQL doesn't.

Maps are a problem. Google maps is as good as it gets for free. MS have a MapPoint web service which is very good but not free.

You may also want to look at LDAP instead of a DB.

Iam running PHP so I could use SNMP from that...

Google Maps will have to do the job, but they might not be detailed enough if Iam talking about a pretty small enough area like a school campus..

Could use XML instead of a DB ? But XML could be slower ?

Rew

Evo wrote:

Yup, sat in the desk behind you for 3 months during the summer

Grand so, that was my first guess.

Iam running PHP so I could use SNMP from that...

Google Maps will have to do the job, but they might not be detailed enough if Iam talking about a pretty small enough area like a school campus..

Could use XML instead of a DB ? But XML could be slower ?

XML is over rated

Presenting data in XML makes devloping applications to use it easier later on.

Storing anything in flat file sis going to make it slow. Yeah there is good SNMP support in PHP but **** support in access points. What hardware is it?

Best to do your own maps but that complicates things. Id break it up in to sections

1\ location detection
2\ map handling
3\ spatial data
4\ tie it together in an LBS

Would be nice to have 2 UI's one for laptops and one for PDA's. Dont bother trying to use one UI that adapts, they dont work well.

For my XDA app (did u see that?) i thew it all in to a DB and just used the last line of the DB as the current pos. Frontend and detection were independant of each other. Would have to be adapted for multiple users though.

U going production with this or just a project?

Evo

U going production with this or just a project?

its part of my bt young scientist project for 06..

So how do I get a users location in relation to an AP layout?

Its based on signal strengths ?

Rew

Thats the 10 mil dollar question really. Coiming up with a system to do that your self is very difficult trust me

Placelab is your best bet. It uses signal strengths to calcualte position. If you don't want accurate positioning you can just assume a position in proximity to the crurrent AP.

Evo

ok.. what I'm thinking of doing because I'm stuck for time is just create a db table with an IP for the AP and then a list of services ( library, cateen, sports hall, etc.. ) to that AP and then see if I can get SNMP to report users ip connected to it ( becuase when a user logs in their IP address is logged ) so then I can match an AP to the user... but what if the user connects to another AP.. DHCP should be setup for clients.. not static ?

Rew

If you can work of MAC addresses that would be better as they are unique for both AP's and clients. What you can get via SNMP depends on the make/model of the AP. If it has a web interface you should be able to screen scrape as a 2nd option.