reg GSM Modem vi RS232

Is TCP/IP Stack necessary in the GSM modem we connect to Mikrotik routerboard via RS232 port to send alert and other sms?

There are multiple models available some with TCP/IP and some without TCP/IP stack.
Also lot of chipset wavecom, Siemens, Motorola, BENQ etc., any specific chipset that Mikrotik recommends in general for optimum performance.

Also is it possible to send alert via sms (using script) if wireless signal falls below a particular RSSI level

Thanks in advance

Vishal,
Go thru this
http://wiki.mikrotik.com/wiki/Monitoring_Network_thru_SMS_Alerts

I have tested ad working fine

Well we have already seen that, however our question is regarding the need of TCP/IP stack support for such GSM modem.

Does GSM modem need TCP/IP Stack support to send sms alert via routerboard.

Also the wiki script shows alert for timed out clients using netwatch, however we need to send alert if the wireless signal degrades beyond a particular RSSI Level

if the cell modem allows you access to the AT command set it will work… ask the vendor if you have direct access to the AT commands on those modems or not.