[asterisk-users] improved SMS?

[Tim Panton]

On 17 Jul 2007, at 11:26, Steve Kennedy wrote:

> On Tue, Jul 17, 2007 at 11:56:35AM +0200, Anselm Martin Hoffmeister  
> wrote:
>
>> Am Donnerstag, den 12.07.2007, 16:57 -0700 schrieb Russ McBride:
>>> Newbie question(s):
>>>  From what I can determine it sounds like the SMS messaging isn't as
>>> robust as it could be (?).  I'm wondering if there's active work on
>>> that right now or if it's more of an issue about PSTN carrier that
>>> one would be using who would be responsible for passing the messages
>>> into the PLMN.
>>> Background-- I'm looking into the possibility of setting up an
>>> emergency messaging system here at the University that would send  
>>> out
>>> voice, SMS, and emails.  Any input relevant to that goal would
>>> probably be appreciated.
>> Hi Russ,
>> my personal experience with short messages is that the system  
>> sometimes
>> chews on them for minutes, sometimes several hours, even inside one
>> mobile network, from cell phone to cell phone. This surely screws  
>> using
>> it as a primary tier emergency system, but as a backup after e- 
>> mail and
>> automated phone-out that could be OK. Sending from web-interfaces  
>> or via
>> Uwhatever-that-protocol-is-called will not improve the overall
>> performance.
>
> SMS was never designed for guaranteed delivery (or guaranteed timed
> delivery). There are options for messages to time out if they're not
> delivered in a specified time, or new messages can override old  
> messages
> that haven't been read yet - but delivery isn't guaranteed.
>
> A phone sending an SMS will try and establish a connection (sort  
> of) all
> the way through to the receiving phone and then deliver the  
> message, if
> it cant it will be sent to the receiving network's SMSC which will  
> then
> try and deliver it. If it gets put into a queue then the delivery time
> will vary drastically depending on the load on the SMSC and other
> network characteristics.
>
> Fixed to SMS always goes through an SMSC, so delivery times vary.
>
> Steve

Just to add, that there is a delivery receipt option you can set on
the sending message. If your code watches for this receipt , it can tell
when/if an SMS has been delivered to the destination phone.

Tim.