SIM900A to Server Communication

I have given the following command AT+CIPSTART=“TCP”,“”,“747”. I got the following as the response.



But at the SocketTest nothing is showing.
(It is expected to show a message that new client is connected right?).
Can you please help me figure it out?

Hi Geetha,

Nowadays the IP address are shared , If you are having a static IP then only you can access the port.
If you are using a hotspot based internet or anything based out of mobile network or LAN then its not going to work. You need static IP to get it working.

Which network are you using?

Also, BSNL provides static IP if you want to get one.


Hi Ravi, I did the following to make static IP . Control Panel>Network and Internet>Network Connections>“Selected the network to which it is connected”>Properties>IPV4>Properties>“Use the folllowing IP”. the screenshot is as given below

I am using JioFi to connect to internet.

In that case what all measure I need to take care to establish the communication?..

Thank you in advance.

You cant make IP static yourself. You are just changing the LAN IP.
Your Public IP which is shown by google needs to be made static. Only your network provider can give it at a extra cost.
Type my IP in google to find out your public IP.

Dear Ravi,

Whether the port forwarding can solve this issue?

with regards,

I have not tried it. But you can see if it works. Also there are firewall problems in Windows 8+ OS.
I had better luck with Windows 7.

ok. whatever happens we need to use public IP.(which is showing when we give myipaddress ) of the PC on which the server is runnning, to connect GSM to server…

i.e we need to give as follows AT+CIPSTART=“UDP”,“PublicIP”,“PortNumber”.

Is my understanding correct?

Correct. You should use Public IP.