The document discusses the evolution of middleware and integration platforms. It describes how middleware emerged to allow disparate systems to communicate by acting as "software glue". Early forms of middleware included homegrown, RPC-based, and object-oriented solutions. More recent approaches include message-oriented middleware, ESBs, and API-based integration using SOA. The WSO2 integration platform is presented as a lightweight, open source ESB and API management platform that supports REST, SOAP, and other integration styles in a configurable and scalable manner.

1. Kasun Indrasiri
Software Architect, WSO2
September 2015

2.  Middleware
 Evolution of Middleware
 Rise of SOA/Web Services/ESB
 Beyond ESB
 WSO2 Middleware Platform
 QnA

3.  What is ‘Middleware’
Image courtesy : http://xpedium.com/images/Bridge.jpg

4.  What is ‘Middleware’
 software that allows organizations to share data between
disparate systems that do not communicate easily
 “software glue” that ties different applications together
http://www.vita.virginia.gov/

5.  Why Middleware?
 Middleware enables applications running across multiple
platforms to communicate with each other .
 Middleware shields the developer from dependencies on
Network Protocols, OS and hardware platforms.
Image courtesy : http://www.technotec.com/images/middle.jpg

6.  Home grown middleware
 Remote Procedure Calls(RPC)
 Object Oriented Middleware
 MOM (Message Oriented Middleware)
 Transaction Processing Monitors

7.  Home grown middleware
 Customized for specific needs
 Extensibility, maintainability and scalability constrains
Image courtesy : http://r1.cygnuspub.com/files/cygnus/image/CGN/2013/JUN/640x360/efi-radius_10964116.jpg

8.  Remote Procedure Calls(RPC)
 Function oriented, synchronous, location transparency
 E.g: ONC RPC, DCE/RPC
Image courtesy : http://www.cl.cam.ac.uk/teaching/1011/CDSysII/12-middleware.pdf
5
Part I: Remote Procedure Call (RPC)
• Masks remote function calls as being local
• Client/server model
• Request/reply paradigm usually implemented with
message passing in RPC service
• Marshalling of function parameters and return value
Caller RPC Service RPC Service Remote
Function
call(…)
1) Marshal args
2) Generate ID
3) Start timer 4) Unmarshal
5) Record ID
6) Marshal
7) Set timer
8) Unmarshal
9) Acknowledge
fun(…)
message
Middleware

9.  Object Oriented Middleware
 Evolved from RPC, Language independent, sync/aync, IDL
 Automated marshalling and unmarshalling,
 CORBA, Java RMI
9
Part II: Object-Oriented Middleware (OOM)
• Objects can be local or remote
• Object references can be local or remote
• Remote objects have visible remote interfaces
• Masks remote objects as being local using proxy objects
• Remote method invocation
object A
proxy
object B
OOM OOM
skeleton
object B
object B
local remote
object
request
broker
/
object
manager
object
request
broker
/
object
manager
Middleware

10.  MOM (Message Oriented Middleware)
 Data transmission through messages, asynchronous
 Message, Queue / Message Queuing and Pub-Sub
 Java Message Service (JMS)
 IBM WebSphere MQ, Active MQ
Part III: Message-Oriented Middleware (MOM)
Communication using messages
Messages stored in message queues
message servers decouple client and server
Various assumptions about message content
Client App.
local message
queues
Server App.
local message
queues
message
queues
Network Network Network
Message Servers

11.  Transaction Processing Monitors
 coordinating and monitoring applications in a distributed
environment
 Leader election, failover
 Tuxedo, IBM CICS, Apache Zookeeper, Hazelcast

12.  Different middleware has different
advantages
 A ‘super-middleware’ is unlikely.
 Organizations can make their own decisions
 Legacy systems may live forever.

13.  Disparate systems (legacy, on-premise and cloud)
 Diverse business requirements

14.  P2P/Spaghetti integration

15.  Replace the direct connections between
systems
 Hub and spoke architecture
 Each system needs only one interface to the
central EAI server

16.  EAI Hub/spoke
 Avoid P2P integration, centralized, single point of failure

17.  EAI Bus

18.  Proprietary and heavyweight
 Support specific vendor's subset of technology
 Not standardized
 Extensibility and scalability issues
 Single point of integration

19.  The idea is to breaking up monolithic systems
into basic services that can be flexibly
orchestrated
 Platform/programming language-neutral
protocol and message format (XML)

20.  Each business functionality is implemented as a
Service and exposed via standard protocols.
 Web services vs SOA?
 Can SOA eliminate P2P Integration?

21.  An ESB is a middleware solution that enables interoperability
among heterogeneous environments based on SOA.
 Stateless and Seamless Integration
 Standard Protocols – SOAP, REST, JSON etc.
 Transports – HTTP/S, JMS, TCP etc.

22.  A simple ESB use case.

23.  Routing

24.  Traffic Filtering
Foo
Bar
Bar

25.  Service Virtualization

26.  Service Orchestration

27.  Transformations

28.  Protocol and Message Format Switching
 HTTP->JMS
 SOAP -> FIX (Financial Information eXchange)

29.  Load Balancing/Failover

30.  QoS : Security, Throttling, Caching
 WS-Security / REST Security
 Throttling – concurrency/rate
 Caching – local/distributed

31.  Exposing/Invoking web services

32.  Exposing/Invoking RESTful interfaces
HTTP Request
GET, POST, PUT, DELETE

33.  Store and Forward
 Guaranteed Delivery
Message Store

34.  Integrate with proprietary systems/protocols

35.  Tasks Coordination

36.  Integrate with web APIs

37.  De facto standard for enterprise integration
 http://www.eaipatterns.com/toc.html

39. The Business of APIs
Grow revenues…
… W ile reducing overhead
“$7bn worth of items on eBay through APIs”
Mark Carges (Ebay CTO)
The API which has easily 10 times more traffic then the
website, has been really very important to us.”
Biz Stone (Co-founder, Twitter)
“The adoption of Amazon’s Web services is
currently driving more network activity then
everything Amazon does through their
traditional web sites.”
Jeff Bar (Amazon evangelist) / Dion Hinchcliffe
(Journalist)
source: SOA and Apis – Impact2013
“The API which has easily 10 times more traffic than
the website, has been really very important to us.”
“The adoption of Amazon’s Web services is
currently driving more network activity than
everything Amazon does through their
traditional web sites.”

40. 88 © 2013 IBM Corporation
Apps, APIs and API Mgmt…
Business
Owner IT
Developer
Consumers
New business opportunities
• New markets
• Increase customers
• Enhance branding
• Competitive advantage
Extend development team
•Increase innovation
•Increase scale
Partner/supplier
alignment
Benefits
Challenges
Business strategy
Infrastructure
• Security
• Creation
• Scalability
Operational control
• Publish
• Analyze
• Monitor
source: SOA and Apis – Impact2013

41.  Managed, monitored, monetized and
versioned business functionalities are
exposed as APIs.
 Exposing business functions to Internal and
external parties (Open APIs, Internal APIs,
Partner APIs)
 Eg: https://dev.twitter.com/docs/api#88

44.  Building a ‘Connected Business’
 Changing an organization to a connected
organization
 Internally and externally connected
 Interactions through services, systems, APIs etc.
Image courtesy : http://www.mydrivingseat.com/the-blog/profound-practical-proven-system-of-business-agility/

48.  The heart of the WSO2 Integration Platform
 A light weight, high performance ESB
 Comprehensive REST, SOAP, WS-* support
 Zero code/completely configuration driven
 100% compliant with EIPs
 Extensible and Scalable

50.  Only Open Source API Management Platform
 API Publisher
 Starting point of API creation
 Control API Lifecycle
 Documentation, Versioning, Authorization, Throttling
 API Store
 Store of published APIs
 Enterprise API Store
 API Gateway ( ESB Features + API-M Handlers)
 Runtime for API calls
 Routing API Traffic

51.  High volume – 6 billion transactions per day

52.  Hybrid Integration

54.  http://www.slideshare.net/ibmapimgmt/soa-and-apis
 http://www.omg.org/news/meetings/workshops/WebServEurope_Manu
al/01-1_Baker.pdf
 http://wso2.com/whitepapers/wso2-whitepaper-soa-and-api-
convergence-strategy-and-tactics/
 http://www.omg.org/news/meetings/workshops/MDA-SOA-
WS_Manual/04-A1_Brown.pdf
 http://www.slideshare.net/udaysaikia/12-middleware
 Evolution of Integration http://wso2.com/whitepapers/the-evolution-of-
Integration-a-comprehensive-platform-for-a-connected-business