Hello there,

We're using ActiveSMS 5.0 to receive SMS and convert them into e-mails.

We get up to 2000 per day, mainly between 2-10 AM, but somehow feel that some of them might not reach us, and among our different hypothesis, we think of a bottleneck effect somewhere.

If I understand properly, all the GPRS modem does is receive the SMS and queues it into the queue database. Only then ActiveSMS really kicks in, reads the queue DB, convert the stored SMS into e-mails and forward them to the SMTP server.

Am I right about this ?


If I am, that means ActiveSMS is not limited to the computing power of its host (since it does not processes SMS on the fly, but stored ones), but rather the throughput of the modem, right ?


If so, can anyone recommend me a very good and reliable modem ? We're using a Siemens MC75-based one with RS232 connection, but fear it might sometimes not be up to the task. But then again, is there any tool to measure this insufficiency ?


Regards,
Aurélien

This diagram show how ActiveSMS works:



ActiveSMS obtains the message from the GSM modem and stores the message in the Message Queue. ActiveSMS that takes the messages from the queue and send the message to the email server.

The bottleneck will be the GSM Network. You can expect to be able to receive 20 messages per minute at the maximum. When messages get congested you can expect performance to fall lower.

Change the GSM modem or Computer hardware will have very little effect on the throughput. The through put is a technical limitation of the GSM network.

Hi and thanks for your quick reply !

I understand there is a throughput limit caused by the GSM network when *sending* SMS, but what about *receiving* them ? Do you know of any similar limitations regarding reception ?

Regards,
Aurélien

Sorry there was an error in my last post (which I have now corrected).

To confirm:

The typical throughput rate for sending SMS messages from a GSM device is around 10 messages per minute. Receiving SMS messages is around 20 messages per minute. If you are both receiving and sending through the transport the throughput rate will reduce significantly. Please note, this is not a limitation of ActiveSMS but a limitation of the GSM network/device.

If you have being sent more messages that can be received through the GSM device, message will be queued on the network. Please note, in an overload situation
the actual effected throughput rate may fail well below 20 message per minute.

Okay, so we ought to be able to receive up to 1200 SMS per hour (60 x 20 SMS) in good conditions... but so far, our peak SMS reception has been 669 messages per hour.

Do you have any idea whether this limit is GSM protocol-related, or phone operator-related (or both, which I presume) ?

EDIT :
I forgot to add (just in case) : we're based in France and mostly using SFR as our phone op.

The 20 messages per minute figure is just a guide.

The overall throughput limit is related to the GSM device and the network.

Also make sure that you have good signal strength.