From AAISP Support Site
Revision as of 10:29, 22 March 2024 by RevK (talk | contribs) (Remove SIP2SIM, add forwarding and tooting)

This page gives an overview to using our services for SMS.

Inbound SMS

This is where text messages are sent to us to deliver to our customers. We provide VoIP numbers in mobile range (07) and in all UK area codes and some special services (e.g. 0800). However, at present, only mobile numbers, and a few of the numbers starting 01 and 02 can receive SMS messages properly from most networks. All of our 01, 02 and 03 numbers can receive SMS messages from Three properly. Attempts to send SMS messages to other geographic numbers (i.e. those starting 01 and 02) cause a call to be made and the SMS message read out by an automated system.

Where SMS messages can be received properly, and this includes all cases where A&A customers send SMS messages through us, the SMS message will be sent on to you by your choice of means. This is based on the incoming SMS message setting in the control pages for your number.

You can put multiple targets separated by a space.

Click to Access the Control Pages

Accessing This Feature

Access is via the Control Pages as follows:

  1. Log in to the Control Pages with your xxx@a login
  2. Click on the number you want to manage
  3. Click the Incoming tab, scroll to the bottom of the page
  4. Enter the details into the SMS Inbound box
Inbound SMS option on Control Pages


If you simply put in an email address, then the SMS message is emailed to you. Additional email headers may be present to specify fields such as User Data Header if present, etc. This is also the default if you do not fill in any incoming SMS handling information in the control pages, but you have an email address defined for the number.


If you put an entry starting http:// or https:// then we will attempt to send the SMS message to you using HTTP (or HTTPS). If the URL ends with a ? or & then an HTTP GET is done with a set of form fields (i.e. name=value) containing information about the SMS message. If the URL does not, then an HTTP POST is done using URL encoded form data. See: SMS API


If you put an entry starting @ and a username and another @ and a hostname, in the format of a fediverse/mastodon account, we will send a direct message to you. Be aware that this is not private from administrators of your instance, and you cannot reply to such messages.


If you put a mobile number (no spaces in it) we will forward the SMS to that number. This is charged to you at our usual SMS rate.

Outbound SMS

Any of our VoIP Numbers can be used to send SMS messages. Just beware that not all numbers can receive an SMS message.

You can send in the following ways:

Multipart texts

Where possible multi-part SMS messages are automatically handled, concatenated before being passed to you, or split from your message into parts. Unfortunately, not all of the systems to which we interconnect handle multi-part messages sensibly, and this can result in a multi-part message being delivered as multiple separate messages.

Itemised billing

Your bill will show the number of SMS messages sent and received per number. The optional XML version of your bill contains detailed information for each message sent or received, including the text content of the message (unless the private setting was used).

Multipart texts are itemised and billed as a single text but billed for the number of parts sent. The XML identifies the number of parts.


The originator field is used to set where the message is from. Normally this is only your phone number. Exceptions are:-

If you have a presentation number set up for your VoIP, this will be used unless you specify an originator. You can specify the presentation number, or the main number. If you ask us, we can allow sending of text-based originators on a per account basis. You will need to be an established customer. This can be withdrawn at any time.

UTF8 Character Sets

The SIP2SIM service does handle all of the GSM character set options, including the 7 bit character set with escaping, the 8 bit binary messages (assuming latin1 character set), and the 16 bit character set with UCS16 surrogates for full unicode.

Internally we convert all messages to UTF-8. If we are sending messages to your own gateway or email they will be in UTF-8.

Our outgoing SMS carriers to external mobiles do not support everything, sadly, and so some characters may get lost on the way. We can only suggest testing yourself to confirm.

SMS error codes

This is a list of internal error codes which may be shown on CDRs if something went wrong:

  • -201 no target found for incoming SMS to customer
  • -204 error while HTTP posting to customer's server
  • -202 and -203 invalid destination email address
  • -301 no destination number
  • -302 and -303 no SMS content to deliver
  • -304 this is a status report, not a normal SMS
  • -305 message billing error - eg we won't send the message as we don't know who to bill
  • -306 too many message parts
  • -702 failed to route message - possible if sending to a totally invalid number
  • -801 and -802 are decoding errors while packing to TPDUs
  • -803 originator address not allowed