Computing in the cloud is fashionable and in many cases extremely cost-effective. But - considering a flawed execution model of rich Web 2.0 applications - will Web applications in the cloud fail to live up to the promise due to performance and security issues? In this presentation - I discuss security and performance issues of Web 2.0 apps in the cloud and talk about the kind of mistakes people make. I wrap up with some thoughts on the game changers

1. Rich Web applications 2011
Crashing in the cloud
Danny Lieberman
dannyl@software.co.il
http://www.software.co.il/wordpress/
Copyright Creative Commons Attribution License by Danny Lieberman

2. Course Content
 Preface
 Security
 Performance
 The future
 Summary

3. Preface
Cloud computing
is fashionable.
Ralf Lauren Fall 2010

4. Preface
But what about
performance &
security?
Coco Chanel circa 1920

5. Cloud and the “security problem”
 Why is security so hard to sell today?
 Complex
 Hard to understand
 Economic benefit to business unclear

6. Cloud and the “security problem”
 Computing as a utility
– Simple
– Easy to measure economic benefit
– Security is built-in

7. Cloud and the “security problem”
 The good news
– The Tier 1 providers are better at security
than you or me
 The bad news
– You still have application software
– Just with a bigger threat surface

8. The cloud threat surface
 CIO mistakes
 Application software

9. The top 3 mistakes CIOS make
 No knowing how much your assets are worth
 asset.val()== undefined
 Writing procedures while attackers exploit
your software
 $p != security.software
 Confusing compliance with
data security
 $c != security.data

10. Rich Web 2.0 applications 2011
2-5 languages
Server stack Message passing in the UI
PC Browser Smartphone Device
3-5 languages
Message passing in the UI

11. Message passing in the UI?
Very bad idea.
Worst dressed at BET Awards 2010

12. Rich Web 2.0 entry points
DB Servers
Interfaces
Server stack PHP, C#, Ruby, J2EE
HTML/Javascript/CSS
Web servers
HTML
XML
PC CSS
Browser Smartphone Device
Javascript
Java
Flash

13. Rich Web 2.0 attack scenarios
 Any kind of code injection
 Server or client returns invalid HTML
 Pages contain dead links
 HTML forms don't match field types expected by controllers
 Client side makes bad assumptions about AJAX services
 Server may attempt to execute invalid SQL queries
 Improper marshaling/un-marshaling
– DB server to Web server
– DB server to application tier
– Web server to browser

14. Rich Web 2.0 vulnerabilities
 Heterogeneous stacks
– Too much chewing gum
 PHP, Ruby, Python
– Flexibility, no static type guarantees
 C#, Java
– Static typed, but only at Web server
– Code complexity increases threat surface
 Redundant code on servers and clients
 Redundant data on servers and clients
 Client-server latency
– Slow HTTP POST attacks

15. Cloud security reference model

16. Security summary

Security Control model looks great

But doesn't mitigate core vulnerabilities

Typing issues

Interface issues

Redundant code, data and tiers

Client-server latency

17. Performance - time is money
 Amazon.com
 100 ms of latency costs Amazon 1% of sales
(http://highscalability.com)
 Google.com
 500ms delay in delivery is a 20% drop in
traffic
(Google VP Marissa Mayer)
 Competing stock trading platforms
 5ms delay is $4M in losses / ms.

18. Web servers 2011
Browser opens
connection.
Server forks a thread
for each connection,
using blocking IO.
Ajax latency:
200-600ms

19. Hardware 2011

What about multiple-processor
concurrency?

Threads don't scale well with multi-cores

Processes are necessary to scale to multi-
core computers, not memory-sharing
threads.

20. Threads are a bad idea

The mixture of threads and modern multi-
core systems add up to some serious race
condition potential.
http://blogs.msdn.com/b/david_leblanc/archive/2007/04/19/why-threads-are-a-bad-idea.aspx

Thread-based networking is inefficient and
very difficult to use.
http://www.kegel.com/c10k.html and http://bulk.fefe.de/scalable-networking.pdf

21. The future of apps in the cloud
The fundamentals of scalable systems are
fast networking and non-blocking design—
.The fundamentals of scalable systems are fast networking and non-blocking design—the rest is message passing
the rest is message passing.
3 technologies will be game changers,I think...
●
Web sockets
●
Node JS
●
Couch DB

22. The future of apps in the cloud
Web sockets

Open a connection to Web
server

It stays open

Pass messages

Eliminates at least 2
processes for every
connection.
(Browser-Server &
Server-Database)

Low Latency:
20-60ms instead of
200-600ms

23. The future of apps in the cloud
Node.js

Javascript on
client and server

No threads

No blocks or locks

UI is HTML & CSS

Asynchronous
message passing
with Web sockets

24. The future of apps in the cloud
CouchDB

Application served out of CouchDB

CouchApp lives in the browser.

No middle tier

Javascript on client and server

UI is HTML & CSS

CouchDB uses Ajax to shove
JSON back and forth.

CouchDB replicates on smart phones

25. Summary

Application vulnerabilities are expensive

100x more expensive to fix after implementation

Potential data loss in the cloud

Security controls don't come cheap
 Time is money

High latency applications less responsive

Your cloud provider charges per CPU cycle

Your costs go up, revenue goes down

Promising new technologies

No middle/data tiers, reduced threat surface

10x lower latency

Your costs go down, revenue goes up.