Audience: Technical Staff validating an SMS channel in preparation for use. This is not easy to do from Surveda directly.

When a mobile connection is established via a new mobile operator or channel, it is useful to perform certain tests to make sure things work as expected, or to get information about how things fail (e.g. user experience, error codes).

SMS Checklist

These are basic tests to verify the connection works:
  • SMS can be sent to a working phone number.
  • Message is received within a short timeframe.
  • "From" in the SMS message is not blank. 
  • "From" in the SMS message is the expected shortcode.
  • SMS message can be replied.
  • Reply gets back to server in a short timeframe.

SMS Content

The following tests validate message length, concatenation, and encoding:
  • Send an SMS that is over 170 characters long.
  • Test maximum length of a message with one accentuated character (e.g. "á"). To test, you can send a long message such as: 

  • Refer to the table in GSM 03.38 Standard to see which characters specifically trigger changes in message length.
  • Test maximum length of a message with at least one local non-western language (e.g. putting the following as the first characters of the sample message above "مرحبا" or "你好").

  • Test messages in a local script or accentuated content and make sure it appears correctly. For example, "aló" could appear as "al[]".

  • Test a long message and see if it is delivered as one or two messages. This can be dependent on the respondent's phone, so test with both a feature phone and a smartphone.

  • Test very long messages - up to 4 concatenated, if you have them - as some phones will truncate messages and just replace with "=more text=".

Failure Mode Tests

The following tests indicate the types of error codes a channel can provide under situations that aren't expected to work:
  • Send to an invalid number (e.g. "111111111111111").
  • Send to an invalid MNO number (e.g. "016-000-00000").
  • Send to an invalid MNO number, of a different MNO than the sender (e.g. "017-000-00000").
  • Send SMS to a landline
  • Send SMS to a nonexistent mobile number
  • Send SMS to a fax line