1.
WhatsApp Architecture
-BY MAHESH BITLA

2.
Why WhatsApp is Popular
2
A
B
C
D
Can send
Multimedia
Can send Location
Can send
Documents
Can send Text
messages
E
F
G
H
It is a Ad free application with Optimum performance.
Can Receive
Multimedia
Can Receive Location
Can Receive
Documents
It is a Ad free application with Optimum performance.
Can Receive Text
messages
Optimum
performance
A

3.
WhatsApp Server Platforms
Backend
 Erlang- programming language
 Jabber Open Source
 FreeBSD- Operating System
 Yaws – Web Server
 PHP
 BEAM - VM to run ErLang
 Custom XMPP
Frontend
 Seven client platforms: iPhone, Android,
Blackberry, Nokia Symbian S60, Nokia
S40, Windows Phone,
 SQLite

4.
How it actually works- Briefly
In whatsApp every user or contact is treated as ACTOR.
User the actor
Aardvark The actor
Aarivinci The actor
Aaronitch The actor

5.
Hi Hi
Tom’s mobile Brad’s mobile
Brad Tom
Tom
The
Actor
Brad
The
Actor
If offline- Stores
the message in
Server
If online –
Sends to Brad

6.
The actor principle in WhatsApp
• User tom wants to send a message to User Brad in through Whatsapp
• First user tom sends a message to tom The Actor and saves the message In user
Tom’s Inbox naming Brad.
• tom The Actor tries to send the message to Brad The Actor and saves the message
in server.
• Brad the Actor tries to send the message to user Brad, Until the user Brad receives
the message ,Brad the actor frequently send the message.
• As soon User Brad comes online, message will Deliver to Brad’s Inbox named Tom.

7.
SqLite
SqLite
Mnesia
Backend
DB
if
online offline
Stores the
message in the
database until he
comes online
Creates the actor
object here for
user1
Creates the actor
object here for
user2

8.
WhatsApp New feature- Encryption
Message Encryption
with a key as tag
Message Decryption By
matching with sender key
Sending through server
Key is the Message Authentication code for that user

9.
What things made Fb to buy WhatsApp
 Up to 2009 Facebook chat was written in ErLang, then moved to another
programming language. WhatsApp written in ErLang with optimum performance
that FB.
 Out of 100 users of FB and whatsapp, 75% are daily active on whatsapp but only
52% are active on FB.
 It can be useful for Facebook INTERNET.ORG initiative.
 Whatsapp framework can be used to increase the Facebook efficiency.

10.
Any Questions??????