SMS Gateway

You can take either of two routes. The first is to use a commercial SMS gateway or the second is to completely develop your own gateway software. From your post, you indicate an interest in the second method.

Sending (and receiving) SMS messages basically involved sending sequences of commands through a port to either a GSM modem or a mobile phone.

Your requirements are as follows:

(1) Choose your programming language. This may well be limited by your choice of platform. For web applications, you may well be restricted to Java, C++ or similar languages that are supported on your hosting platform.

(2) Get either a suitable GSM modem or a mobile phone with a PC connection. I would strongly suggest a Nokia.

(3) Become familiar with connectivity issues, error handling, AT GSM commands and the sending and receiving of SMS messages. The best resource I have seen is here http://www.developershome.com/sms/

More information here http://www.activexperts.com/activcomport/tutorials/sms/
ActiveExperts supply their own API but do not disregard their site even though their API does not interest you. They have a great deal of information on their site that will help you.

More resources that will help you are:
http://www.activexperts.com/xmstoolkit/atcommands/nokia/
http://www.parallax.com/Portals/0/Education/custapps/Nokia_AThelp.pdf
http://tuxmobil.org/phones_linux_sms.html
http://www.developershome.com/sms/smsLinux.asp
http://www.gnokii.org/

(4) Develop and troubleshoot your software


What you are undertaking is not a simple task but it is something that you can build on over time once you get a basic version working.

Just a follow up to my post above... having looked at your profile, you could develop your software in VB as long as your web hosting platform supports it.

Hi Mike

and thanks for replying.

Yes i am well aware that it is a huge task to develop a sms gateway. But this is what i am going to do.
And yes my host supports asp.net 3.0 and up

But let me hear your recommendations regarding hardware requirements

1) i am talking bulk sms 5000+ a day and accross scandinavian and europe
2) I want to route the sms through smtp (email to sms) "that would only one way direction". and only a very
    little string of text in each sms            

What type of GSM modem are we talking here ? (one from Nokia ?)    
and are you familiar with which telecompanies that providing as to their telenet (i assume that is through sim card)
Can you recommend a european telecom ? (again excuse my lack of experience)

Thanks

sorry

to quick to submit

What type of GSM modem are we talking here ? (one from Nokia ?)  and the size of it  
and are you familiar with which telecompanies that providing access to their telenet (i assume that is through sim card)