How reliable is SMS text messaging?

[neilrr]

I hardly ever text anybody so don't know a whole hell of a lot about the way it works.

Has anybody who is familiar with it ever come across this sort of thing before?

Recently I drove 100 miles one way to look at a car with a friend & his elderly mother for whom the car was intended. We had an appointment for 7.30 p.m.

We arrived at the venue at 7.35 p.m. to find nobody there & a note on the door saying "Sorry, closed today due to illness."

At 7.50 p.m. while standing outside the place I received a text message cancelling the appointment. The text message had been sent at 8.30 that morning, 11 hours before I received it.

I'm furious with the bloke for not calling me & sending us on a fool's errand. His attitude is 'I sent a text, if you didn't get it that's tough & not my fault. Take it up with your mobile co.'

Is it normal for these things to get lost or delayed occasionally / regularly or was I just unlucky?

 

[Sp!ke]

Text messages cannot be relied upon. 99% get through but no mobile provider provides service levels on text messages and thats why they never get used by business for critical applications or alerting mechanisms.

(see how long your own text takes at midnight on new year)

 

[Dieselman]

There should normally be a receipt sent to the sender to confirm the text has been delivered though.

 

[MBManInKen]

The point to remember is that SMS is not a conversational medium, like voice telephony. It is a message based system, similar to email, based on a store-and-forward principle.

Sending someone an SMS comes with no guarantees about delivery times. Furthermore, it's a "best effort" service as opposed to guaranteed delivery and indeed networks can delay and even drop SMS messages when under heavy load or in specific bottlenecks.

On the other hand, SMS sits in the signalling and does not require much network resources, so if you're in an area with patchy signal, you might find that an SMS actually was able to get through even though you could not establish a voice channel.

The weakest point is the radio link between the handset and the core network. Once a message gets onto the core network, is has a good chance of getting there.

The best advise is: by all means use SMS, but if the message is critical and you haven't received an answer from the other party, then seek alternative ways of contact.

 

[Sp!ke]

There should normally be a receipt sent to the sender to confirm the text has been delivered though.

Only if the sender requests it by turning on that option.

 

[MBManInKen]

There should normally be a receipt sent to the sender to confirm the text has been delivered though.

Unfortunately, some SMSC equipment does return a delivery receipt, even if the message is buffered in the SMSC but not yet delivered to the handset. This is getting rarer though as the protocol has been tightened up.

Obviously, the sender must have his/her handset configured to request and process such receipts.

 

[evdok]

I've had tex's that we're sent hours ago! But then i am with orange

 

[Dieselman]

I've had tex's that we're sent hours ago! But then i am an orange

 

[Mark300SL]

I have had real problems with Vodafone recently, Calls are takign a lot longer to set up - almost 30-40 seconds at times and text messages are hit and miss. I sent an important one (and a voicemail!) to DorianT on Wednesday and he still hadnt received either tonight!
Whilst I know they are using IP based backbones it almost looks like talktalk has taken over running the network.

If we were not tied in for another year I would be seriously considering swapping providers and thats after 10 years almost faultless service with them. My account manager cant do anything as it appears to be network wide - but assures me Vodafone are looking in it!

 

[whitenemesis]

Unfortunately, some SMSC equipment does return a delivery receipt, even if the message is buffered in the SMSC but not yet delivered to the handset. This is getting rarer though as the protocol has been tightened up.

Obviously, the sender must have his/her handset configured to request and process such receipts.

I was assured by Orange that I should never receive a false positive i.e. delivered receipt when in fact sms was not received by handset of receipient.

But it is possible (and fairly common) to receive false negatives i.e. delivery pending / failed when in fact the sms has been received.

 

[Dieselman]

I sent an important one (and a voicemail!) to DorianT on Wednesday and he still hadnt received either tonight!

In my experience Vodafone are the worst provider for corporate mobile systems. Voicemail can regularly take 24Hrs, the coverage is seriously patchy and the mobex system is seriously unreliable.

I thought Celnet were bad until experiencing Vodafone.

 

[MBManInKen]

I was assured by Orange that I should never receive a false positive i.e. delivered receipt when in fat sms was not received by handset of receipient.

It should be pretty rare, but I can still think of scenarios where the above would be theoretically possible. On the other hand, current equipment and updated protocols should indeed prevent the above from happening. At least within the UK, when a foreign network is involved, all bets are off.

But it is possible (and fairly common) to receive false negatives i.e. delivery pending / failed when in fact the sms has been received.

Agreed - quite possible to think up scenarios where this would happen, in fact the recipient could end up with mutliple copies of the same message as a consequence.

 

[MBManInKen]

Interesting comments! Vodafone ought to be much better, their network in many respects has been better than that of others, but of course they might be letting things slip. Worth bearing in mind that the experience different people get can vary greatly depending on where in the country you are.

If I had to nominate the worst network in the UK, I'd put T-Mobile forward, even worse than the dire lot of 3 in may respects .

 

[neilrr]

Sending someone an SMS comes with no guarantees about delivery times. Furthermore, it's a "best effort" service as opposed to guaranteed delivery and indeed networks can delay and even drop SMS messages when under heavy load or in specific bottlenecks.

The best advise is: by all means use SMS, but if the message is critical and you haven't received an answer from the other party, then seek alternative ways of contact.

Thanks. It seems obvious to me too.

 

[whitenemesis]

Curiously sms have no position legally. They cannot be cited as evidence. Whereas voice communications can!?

 

[Rory]

Not sure if it's still the same but I don't think O2 has receipts for texts sent (although I vaguely recall that you can send a code with the text so the receiving phone will send a receipt).
I guess 99.9% or whatever work fine without thinking about it, but you really notice the 0.1% that are time critical and don't work. We had a problem when our daughter was regularly travelling by train and she'd text to say she was 15mins away and then she'd arrive at the station and we weren't there. That happened a couple of times then she switched to just calling us.

 

[evdok]

LOL

 

[Sp!ke]

I have had real problems with Vodafone recently, Calls are takign a lot longer to set up - almost 30-40 seconds at times and text messages are hit and miss. I sent an important one (and a voicemail!) to DorianT on Wednesday and he still hadnt received either tonight!
Whilst I know they are using IP based backbones it almost looks like talktalk has taken over running the network.

If we were not tied in for another year I would be seriously considering swapping providers and thats after 10 years almost faultless service with them. My account manager cant do anything as it appears to be network wide - but assures me Vodafone are looking in it!

Really?

I have the opposite experience. I have a personal vodaphone and a company O2 handset and the O2 one is not a patch on the Vodaphone on so many levels.

Really surprised by your post tbh and wondering if its handset of SIM related rather than network.

 

[stevesey]

Text messages cannot be relied upon. 99% get through but no mobile provider provides service levels on text messages and thats why they never get used by business for critical applications or alerting mechanisms.

Yep basically they are not guaranteed delivery - which is why the Westiminster parking pay by text scheme seems so stupid - did they not involve a Telecoms consultant?

My daughter has a habit of texting me when she wants picking up etc - and I'm always telling her to phone a) because it's not guatanteed and b) simple common sense that my phone may off, in another room etc and she won't known I haven't got the message.

Likewise delivery receipts don't tell you message has been read, just arrived at the phone (of even that).

 

[KillerHERTZ]

You can force refresh your phone to pick up any pending messages

If you have a Nokia and you think that you havent recived a txt message that should have arrived.

Go into Settings > Phone > Nework > Operator selection.

Set it to manual, it will search the avaible Networks. Select yours and any pending messages will arrive straight away.

Or, for newer Nokia's, simply set your phone to offline & then back to General.