Computer networks have redundant links between machines so that if one fails others can take over to guarantee deliverability. However, as we move up the stack to Person to Person communication protocols via the net, this redundancy gets dropped. Fallback messaging is a means to allow communication between two people to continue even if some of the underlying service providers fail. Opensource clients like ayttm, eb, gaim, kopete, and transports like jabber have the edge here, let's find out how and why. More info here: http://tech.bluesmoon.info/2004/09/fallback-messaging.html

1. Fallback Messaging
Philip Tellis / philip@bluesmoon.info
Yahoo!
Linux Bangalore 2004 / 2004-12-02
Linux Bangalore 2004 / 2004-12-02 Fallback Messaging

2. $ whoami
Philip Tellis
philip@bluesmoon.info
@bluesmoon
yahoo
geek
Linux Bangalore 2004 / 2004-12-02 Fallback Messaging

3. How do you chat?
Which IM programs do you use?
How many accounts on each?
Do you communicate with the same people over multiple
services?
How often do you use email/SMS to communicate with
these people?
Linux Bangalore 2004 / 2004-12-02 Fallback Messaging

4. Does the server decide whether you can chat or not?
How often has a service gone down for maintenance while
you’re in a conversation?
What happens to your conversation?
What happens to your train of thought?
What happens to logs of the conversation – if any?
Linux Bangalore 2004 / 2004-12-02 Fallback Messaging

5. Do you know your friends by their names or their handles?
Linux Bangalore 2004 / 2004-12-02 Fallback Messaging

6. Act 1, Scene 1, Take 1
Philip and Manish are chatting on MSN about their project
MSN server goes down
Start Y!M, continue conversation
Net goes down, only email working
Send email/SMS saying that we can’t chat anymore
Philip combines all the logs to post to the website
Linux Bangalore 2004 / 2004-12-02 Fallback Messaging

7. Act 1, Scene 1, Take 1
Philip and Manish are chatting on MSN about their project
MSN server goes down
Start Y!M, continue conversation
Net goes down, only email working
Send email/SMS saying that we can’t chat anymore
Philip combines all the logs to post to the website
Linux Bangalore 2004 / 2004-12-02 Fallback Messaging

8. Act 1, Scene 1, Take 1
Philip and Manish are chatting on MSN about their project
MSN server goes down
Start Y!M, continue conversation
Net goes down, only email working
Send email/SMS saying that we can’t chat anymore
Philip combines all the logs to post to the website
Linux Bangalore 2004 / 2004-12-02 Fallback Messaging

9. Act 1, Scene 1, Take 1
Philip and Manish are chatting on MSN about their project
MSN server goes down
Start Y!M, continue conversation
Net goes down, only email working
Send email/SMS saying that we can’t chat anymore
Philip combines all the logs to post to the website
Linux Bangalore 2004 / 2004-12-02 Fallback Messaging

10. Act 1, Scene 1, Take 1
Philip and Manish are chatting on MSN about their project
MSN server goes down
Start Y!M, continue conversation
Net goes down, only email working
Send email/SMS saying that we can’t chat anymore
Philip combines all the logs to post to the website
Linux Bangalore 2004 / 2004-12-02 Fallback Messaging

11. Act 1, Scene 1, Take 1
Philip and Manish are chatting on MSN about their project
MSN server goes down
Start Y!M, continue conversation
Net goes down, only email working
Send email/SMS saying that we can’t chat anymore
Philip combines all the logs to post to the website
Linux Bangalore 2004 / 2004-12-02 Fallback Messaging

12. The idea behind fallback messaging
People care about people, not protocols
Conversations should not be service dependent
Conversation should be continuous even if the service
changes
Person-person messaging approaches pc-pc messaging
Linux Bangalore 2004 / 2004-12-02 Fallback Messaging

13. So what does fallback messaging do?
Automatically pick a protocol to use for messaging
Automatically switch protocols if one goes down without
worrying the user
A single log file irrespective of protocol
Represent a person as a single entity rather than a bunch
of different handles
Linux Bangalore 2004 / 2004-12-02 Fallback Messaging

14. What’s needed?
A single client that talks multiple protocols
The client should group different accounts of a contact into
a single entity
The client should be able to switch between accounts
Perhaps an ability to prioritise the order of fallback
Linux Bangalore 2004 / 2004-12-02 Fallback Messaging

15. Act 1, Scene 1, Take 2
Philip and Manish are chatting on MSN about their project
MSN server goes down
The client switches to Y!M
Net goes down, only email working
Client switches to email/sms
User is notified that he’s now in async mode
The client has a combined log of everything communicated
Linux Bangalore 2004 / 2004-12-02 Fallback Messaging

16. Act 1, Scene 1, Take 2
Philip and Manish are chatting on MSN about their project
MSN server goes down
The client switches to Y!M
Net goes down, only email working
Client switches to email/sms
User is notified that he’s now in async mode
The client has a combined log of everything communicated
Linux Bangalore 2004 / 2004-12-02 Fallback Messaging

17. Act 1, Scene 1, Take 2
Philip and Manish are chatting on MSN about their project
MSN server goes down
The client switches to Y!M
Net goes down, only email working
Client switches to email/sms
User is notified that he’s now in async mode
The client has a combined log of everything communicated
Linux Bangalore 2004 / 2004-12-02 Fallback Messaging

18. Act 1, Scene 1, Take 2
Philip and Manish are chatting on MSN about their project
MSN server goes down
The client switches to Y!M
Net goes down, only email working
Client switches to email/sms
User is notified that he’s now in async mode
The client has a combined log of everything communicated
Linux Bangalore 2004 / 2004-12-02 Fallback Messaging

19. Act 1, Scene 1, Take 2
Philip and Manish are chatting on MSN about their project
MSN server goes down
The client switches to Y!M
Net goes down, only email working
Client switches to email/sms
User is notified that he’s now in async mode
The client has a combined log of everything communicated
Linux Bangalore 2004 / 2004-12-02 Fallback Messaging

20. Act 1, Scene 1, Take 2
Philip and Manish are chatting on MSN about their project
MSN server goes down
The client switches to Y!M
Net goes down, only email working
Client switches to email/sms
User is notified that he’s now in async mode
The client has a combined log of everything communicated
Linux Bangalore 2004 / 2004-12-02 Fallback Messaging

21. Act 1, Scene 1, Take 2
Philip and Manish are chatting on MSN about their project
MSN server goes down
The client switches to Y!M
Net goes down, only email working
Client switches to email/sms
User is notified that he’s now in async mode
The client has a combined log of everything communicated
Linux Bangalore 2004 / 2004-12-02 Fallback Messaging

22. Can we do this today?
FOSS clients like gaim and ayttm can do it
Still needs some work
FOSS clients have the edge
Linux Bangalore 2004 / 2004-12-02 Fallback Messaging

23. Do we really need it?
Probably in very few situations, but we sure want it :P
Data transfer over IM is an application
Linux Bangalore 2004 / 2004-12-02 Fallback Messaging

24. The future of IM
Everyone’s talking about IM interoperability
Sending structured data and not just human readable
conversations over IM
IM transports as a commodity with value added services
above it
Linux Bangalore 2004 / 2004-12-02 Fallback Messaging

25. Thank you
http://tech.bluesmoon.info/2004/09/fallback-messaging.html
Linux Bangalore 2004 / 2004-12-02 Fallback Messaging