Bug with multipart and SMPP

Bug with multipart and SMPP SearchSearch
Author Message
Nikos Mavrakis
New member
Username: Nmavra

Post Number: 42
Registered: 05-2007
Posted on Wednesday, February 24, 2010 - 02:38 pm:   

I think I have found a bug regarding multipart messages on SMPP. I run wireshark to capture the network traffic between the SMSC and NowSMS and I submit the following long message:

http://localhost/?PhoneNumber=123123&SMSCRoute=SMSC1&user=test&password=test&Rec eiptRequested=Yes&Text=111111111122222222223333333333444444444455555555556666666 6667777777777888888888899999999990000000000AAAAAAAAAABBBBBBBBBBCCCCCCCCCCDDDDDDD DDDEEEEEEEEEEFFFFFFFFFFGGGGGGGGGG

The message arrives on the phone scrambled. When I take a look on the captured network traffic I see that the submit_sm contains exactly the same scrambled message as I received it on the phone. I can provide you with network traffic capture file.
Des - NowSMS Support
Board Administrator
Username: Desosms

Post Number: 1841
Registered: 08-2008
Posted on Wednesday, February 24, 2010 - 04:21 pm:   

Hi Nikos,

Select your SMPP connection in the "SMSC" list and press "Properties".

Under "Advanced Settings" there is a configuration option that says "Encode long text messages with 7-bit packed encoding". If this setting is checked, UNcheck it, and press Ok, Ok, Apply to save the change. (If the setting is UNchecked, check it.)

Basically, the SMPP standard is not clear about which encoding should be used, so it works differently with different SMPP service providers. Some want 8-bit encoding, others want 7-bit packed encoding.

There's no way to know which one to use with a provider other than trying both.

--
Des
NowSMS Support
Nikos Mavrakis
New member
Username: Nmavra

Post Number: 44
Registered: 05-2007
Posted on Thursday, February 25, 2010 - 10:49 am:   

Hello Des, thanks for your reply, however it seems that this setting didn't have any effect on our long message.

The "Encode long text messages with 7-bit packed encoding" was already checked, and even unchecking it didn't seem to have any effect either.
Des - NowSMS Support
Board Administrator
Username: Desosms

Post Number: 1853
Registered: 08-2008
Posted on Thursday, February 25, 2010 - 04:20 pm:   

Hi Nikos,

Make sure you restart the NowSMS server after changing this setting. Also exit out of the configuration program, and make sure that the setting change was saved. (It is confusing to change this setting, because you must press OK twice to save it, and then Apply.)

Next, since you have used Wireshark to previously capture a trace, try it again. You should see that the text is encoded differently when the setting is unchecked. When this setting is unchecked, you will see the regular text of the message in the capture file.

If the message is still garbled, then this provider might not support long messages. There is one more encoding that you can try. Leave the 7-bit packed encoding setting UNchecked, but check "Use TLV parameters for port numbers and segmentation". This uses yet another, less widely supported in the real world, encoding technique.

--
Des
NowSMS Support
Nikos Mavrakis
New member
Username: Nmavra

Post Number: 45
Registered: 05-2007
Posted on Friday, February 26, 2010 - 09:51 am:   

Hello Des,
This actually worked by having the "Encode long text messages with 7-bit packed encoding" UNCHECKED, and then restarting the NowSMS setting.
I did not need to check "Use TLV parameters for port numbers and segmentation", it worked without it without problems!

Thank you!