Gchat SMS? How the fsck does it work?
April 5, 2011 1:03 PM Subscribe
How does the SMS feature in Gmail work? I know there's some kind of base of phone numbers used for it, but I assume those numbers send out thousands of texts per day; how does a reply end up at my account, instead of someone else's? If someone replies to one of my SMS messages sent from Gmail in a month, will the reply still be connected to me?
I am curious about this as well, as I use Google Voice and I expect that it is handled the same way. Google Help implies that the answer to your last question is yes. I have texted replies by reusing a 617-xxx-xxxx number and they have made it to my intended recipient, even weeks later.
I would guess that Google uses a combination of the destination number and the number of the replying phone (by caller ID) to link the reply to you.
posted by UsernameGenerator at 3:07 PM on April 5, 2011
I would guess that Google uses a combination of the destination number and the number of the replying phone (by caller ID) to link the reply to you.
posted by UsernameGenerator at 3:07 PM on April 5, 2011
There's additional metadata in SMS beyond just your number and the message.
While I don't know the specifics, I'm pretty sure the info needed for reply is encoded in there somewhere.
Note that when you use Google Voice to send an SMS (like from the web app), it shows up as being from your GV number on the recipient side, so there it's easy to handle replies. Gchat doesn't give you a specific phone number, so they're either using a message id in the sms, account id, something like that so they can tie it back in the reply.
posted by wildcrdj at 5:22 PM on April 5, 2011
While I don't know the specifics, I'm pretty sure the info needed for reply is encoded in there somewhere.
Note that when you use Google Voice to send an SMS (like from the web app), it shows up as being from your GV number on the recipient side, so there it's easy to handle replies. Gchat doesn't give you a specific phone number, so they're either using a message id in the sms, account id, something like that so they can tie it back in the reply.
posted by wildcrdj at 5:22 PM on April 5, 2011
kaibutsu, I'm assuming that you are asking about the Gmail Labs feature "SMS (text messaging) in Chat" and you are asking about the perspective of the individual who receives the SMS from Google.
I tried this out myself on a new Google account and my own phone. I sent an SMS to my phone from Google Chat and received a text message with my Chat message from 406-205-xxxx. I sent an SMS to 406-205-xxxx from my phone and it showed up in Google Chat. I sent an SMS to 406-205-xxxx from a different phone number and it did not show up in Google Chat. I wanted to try to spoof caller ID information from my personal phone to test my theory (that Google made the association by the incoming phone number), but I couldn't get Skype to cooperate.
Relevant for my experiment: I am in the US and used a different Google account that is not linked to my Google Voice account.
wildcrdj, I wasn't very clear, but when I mentioned Google Voice, I was talking about receiving a text message from one of my contacts on one of my (GV-associated) forwarding phones. I believe it operates the same way as a recipient of a GChat SMS: Google uses a dummy number as the caller ID of the SMS so that users can directly reply to that dummy number and have it travel to the right destination.
I know in my experience this works, but I'm not sure what metadata is used. Maybe the how question should be asked on Google's forums.
posted by UsernameGenerator at 9:12 PM on April 5, 2011
I tried this out myself on a new Google account and my own phone. I sent an SMS to my phone from Google Chat and received a text message with my Chat message from 406-205-xxxx. I sent an SMS to 406-205-xxxx from my phone and it showed up in Google Chat. I sent an SMS to 406-205-xxxx from a different phone number and it did not show up in Google Chat. I wanted to try to spoof caller ID information from my personal phone to test my theory (that Google made the association by the incoming phone number), but I couldn't get Skype to cooperate.
Relevant for my experiment: I am in the US and used a different Google account that is not linked to my Google Voice account.
wildcrdj, I wasn't very clear, but when I mentioned Google Voice, I was talking about receiving a text message from one of my contacts on one of my (GV-associated) forwarding phones. I believe it operates the same way as a recipient of a GChat SMS: Google uses a dummy number as the caller ID of the SMS so that users can directly reply to that dummy number and have it travel to the right destination.
I know in my experience this works, but I'm not sure what metadata is used. Maybe the how question should be asked on Google's forums.
posted by UsernameGenerator at 9:12 PM on April 5, 2011
This thread is closed to new comments.
posted by madcaptenor at 2:06 PM on April 5, 2011