1. Interoperability: Making devices talk to each other CSE481M: Home Networking Capstone April 13 th, 2011

2. Devices on an island Need a language in common if they want to talk to each other

3. More devices on an island Standardized languages reduce the number of languages each device needs to know

4. Designing a language (standard) A big challenge: making it future proof New devices and functionality will emerge

5. How to design a future-proof language? Define the basics that everyone understands Implement extension dialects DLNA, Z-Wave, ZigBee, … What is the Speakeasy approach?

6. Can there be one universal language? Has not happened so far …. Unlikely: different concerns and capabilities

7. Interpretation Allows devices that speak different languages to talk Without requiring them to learn new languages

8. Another dimension of being future proof Being able to talk to devices with new languages

9. Enabling interpretation in practice Ship interpreters with the system Acquire dynamically From the cloud (as in Windows) From the device (as in Speakeasy) Successful model? Bootstrapping problem Discovering devices Establishing some common basis

10. Systems perspective: The ability to talk is not enough Restricting communication Simultaneous (conflicting) talking Need equivalents of social rules

11. Implementing communication rules Closed systems (monolithic) Easy to implement the first time but difficult to extend Extensible systems Need rule specification and enforcement mechanisms

12. The ugly truths of designing standards Technical fights E.g., how many bytes for device type? Non-technical fights To give edge to your company Example: Stories of Cisco filling IETF rooms Just coz Example: point vs. comma in ALGOL => Long drawn out process Compromises can render the final product unusable ZigBee  Z-Wave

13. Each company makes a selfish decision Even if involved in the standardization process Chicken-and-egg problem Little first-mover advantage Testing is hard  Major teething issues Most never take off The hard facts of adopting standards