The document discusses the challenges of building cloud and hybrid applications and positions Azure Service Bus as a reliable enterprise messaging service. It covers key messaging concepts such as asynchronous message delivery, pub/sub functionality, and cross-entity transactional processing. The conclusion highlights that while messaging provides benefits, it cannot solve all issues inherent to distributed systems, such as outages and eventual consistency.

1. Azure Service Bus: The Messaging
Backbone for Cloud Applications
Sean Feldman

2. What we’ll cover today
• What are the challenges building cloud and hybrid applications?
• What makes Azure Service Bus a good enterprise messaging service?
• Messaging concepts supported by Azure Service Bus
• Conclusions

3. What are the challenges
building cloud and hybrid
applications?

4. The evolution of a simple app
from a single server hosting
everything

5. Multi-server world

7. Scaling out vs scaling up

10. Does a user need to wait?

11. Leveling the load

12. Example: Amazon order

13. Applications evolving into systems

14. Messaging

15. Why Azure Service Bus

16. Cloud native messaging
service

17. Reliable asynchronous
message delivery

18. At least once delivery of a
message

19. Boundaries and trust

20. Better positioned compared
to other messaging services

21. Messaging concepts supported by
Azure Service Bus

22. Disclaimer
.NET 5 Azure.Messaging.ServiceBus

23. Queues: send and receive

24. Receive mode

25. Payload and metadata

26. Competing consumers

27. Competing consumers (seeding queue)

28. Competing consumers (processor)

29. Competing consumers (processor events)

30. Pub/Sub
Topic
Subscription
Rule
- Filter
Boolean, correlation or SQL
- Action
…

31. Pub/Sub (example)
topic
all-messages
BooleanFilter(true) / SQL(1=1)
important-messages
Correlation(Label=‘important’)
Action(SET level=‘vip’)
regular-messages
SQL(Label NOT in (‘important’))
Action(SET level=‘regular’)

32. Pub/Sub (creation of topic/subscriptions/rules)

33. Pub/Sub (publishing)

34. Delivery count and dead-lettering
Max Delivery
Count
DLQ

35. Dead-lettering (queue setup)

36. Dead-lettering (results)

37. Batching

38. Sessions

39. Sessions (enabling sessions)

40. Sessions (receiving)

41. Cross-entity transactional processing (Send-Via)
c
B
A
Incoming

42. Cross-entity transactional processing
c
B
A
transfer
Incoming

43. Cross-entity transactional processing

44. Cross-entity transactional processing
bQueue
aQueue
test

45. And much
more…
• Scheduling
• Forwarding
• De-Duplication
• Large message support
• etc.

46. CONCLUSIONS
• Messaging is not a silver bullet
• No distributed transactions
• Outages and downtime are guaranteed
• Spikes
• Eventual consistency
• 24/7 operational status (system never sleeps)
• Standard vs Premium namespace

47. THANK YOU
@sfeldman feldman.sean@gmail.com weblogs.asp.net/sfeldman