We do this mainly to bypass proxies, especially transparent proxies - your ISP will often have a transparent proxy intercepting traffic on port 80, which you may be unaware of. Such proxies can cause various anomalies, like poor throughput/outages, DNS resolving problems, and even duplicate submissions. Additionally we can offer better performance ourselves via direct access to, say, port 5567.

You can fall back to port 80 if you have firewall-related problems connecting to us (but we recommend that you rather take the time to allow outgoing access to ports 5567 and 7512 via your firewall). To do so, simply remove :5567 (or similar) from the URL.

http://www.bulksms.co.uk:5567/eapi/submission/send_sms/2/2.0?username=john
&password=xxxxxxxxx&dca=16bit&msisdn=441231234&message=004200430044

0042 is in hexadecimal, which is 66 in decimal, and corresponds to ASCII 66, or B. Do not leave out the zeros from this example. This example should display correctly on almost every phone, but will appear no different to you than just sending BCD as a normal SMS.

Here's an example with some Arabic characters: 0600060106020603060C. Don't expect it to display correctly unless your phone supports Arabic characters (which is only likely if you are in an Arabic-speaking country).

You will find Unicode charts (which map characters to codes) at www.unicode.org/charts.

If you need to find out how to encode smart messages (ringtones, operator logos, picture messages, etc) for Nokias, the best place to look is at www.forum.nokia.com. You can create an account for free. Log in and go to Developer Home: Resources: Technologies: Messaging: Short Messaging: Support / FAQs: Smart Messaging FAQ. This is the best resource we know of.

Similarly, under Short Messaging: Documents, look for Smart Messaging Specification, Revision 3.0.0, which also has some useful examples.

For free (non-commercial) software to do encoding for you, have a look at Mike Kohn's Ringtone Tools - a great set of very useful utilities for ringtones, logos, etc with support for multiple cell manufacturers' products. Note: SCKL headers are not used in 8-bit mode, so we recommend using, for ringtones for example, ringtonetools -u -s 280. Your resultant 8-bit messages should have up to 280 characters (or more correctly put, up to 140 octets, where FF is an octet, and not 140 characters as the Ringtone Tools software implies. Thereafter (if you need to support concatenated messages), we recommend that you vary the message id in the headers for each set of messages produced. So, if your output from ringtonetools was 0B0504158100000003010201..., you could cycle the message id of 01, in the range from 00 to FF. Therefore, your next pair of messages' headers could be:
0B0504158100000003020201...
0B0504158100000003020202...
where the id 01 has been cycled to 02. This will prevent your multiple messages from the same source number to the same mobile causing problems (through delayed or non-delivery of the concatenated parts for instance, and/or multiple submissions to the same mobile over a short period).

URL: http://192.168.0.1/blah
message displayed: push

Here's a complete breakdown of the message:

UDH

WSP headers

WBXML section

You will find the OMA Wireless Session Protocol Specification and WAP Service Indication Specification here.

WBXML is a binary representation of an XML document. The specification is here, but you should rather look at a library to do the encoding for you, e.g. libwbxml - a C library for creation and decoding WBXML, plus command-line programs. An encoder will allow you to automatically generate the WBXML from e.g.:
<si><indication href="http://192.168.0.1/blah">push</indication></si>

Note that the example above excludes an si-id, in which case the si-id defaults to the href parameter. A mobile will typically overwrite an already-stored message which exists with the same si-id (which in this case above means the same href, effectively). At the same time, it will typically notify the user that a new push was received, but be aware that some handsets might not do so.

Breakdown:

06050423F40000: Standard User Data Header (port 23F4) for a vCard.

The rest of the hex above is simply the following text (as per the vCard specification), encoded to hexadecimal octets:
BEGIN:VCARD<CR><NL>
VERSION:2.1<CR><NL>
N:Doe;John<CR><NL>
TEL;PREF:+441231234<CR><NL>
END:VCARD<CR><NL>

(note the termination of each line with a carriage return-newline pair).

Compatibility: vCards should work on most Nokias. We're not sure about other makes. However, vCards are not based on a proprietary (or even a Nokia-specific) specification.

For more on vCard (and vCalendar) see www.imc.org.

See the Nokia Smart Messaging FAQ (at forum.nokia.com) for examples.