Patrick Mignott wrote: >hi all, >what is the best AT modem to work with kannel? and the reasons for you >opinion please. >
There are no good GSM modems to use to handle incoming SMS messages. The way SMS is implemented prohibits it. While I realize that many people here regularly use GSM modems to receive SM's, and that the ability to do so is an attractive feature for many developers, please consider what happens if your service is a raging success. Your user's SMS-MO is accepted by an operator's SMSC, and stored for future forwarding. It will then be forwarded to the GSM modem as an SMS-MT. Since the SMSC can only deliver 1 message every few (3-6) seconds with NO windowing whatsoever, if messages come in more quickly, they will be stuck in the operator's SMSC. Depending on the SMSC vendor, the storage space may be shockingly limited, and the behavior of the SMSC may become rather pathological once the database gets 'too full'. (Ahem... I am thinking of a certain... umm.. Finnish vendor as I write this.) Using the AT modules for development is not a problem -- the problem is that a successful SMS service, especially a "quiz show" type application, will cause spikes of activity that can disable SMS on some or all of an operator's network. Be careful. You do not want to break the networks you are using, and you do not want to be disconnected because you came up with a service everybody wants to use. HTH, David WHITE CONNECT AUSTRIA
