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Jumat, 29 Agustus 2014

Roadmap: Becoming an Enterprise Java Developer

Roadmap: Becoming an Enterprise Java Developer

Spending time in a classroom learning the different facets of Java programming is interesting, but my students inevitably ask, "Where is the money to be made in Java programming?" A quick perusal of Monster.com or Dice.com will show you a current state of the employment market. The requirements may be different depending where you live, but by and large the bulk of the higher paying jobs in the Java industry are in the enterprise domain (J2EE).
You like Java and you want a selection of good paying jobs, so you are on board to become a J2EE architect. But where do you start? There are so many Java technologies, which ones should you learn? In what order should you learn them? What are the dependencies? What path will give you the best understanding?
The answers to these questions are subjective, but in this article I want to share my opinion of a roadmap to follow and a listing of resources that you can use to meet each objective in becoming a strong Enterprise Java Developer. If you are already a proficient Java programmer, read through each section and make sure that you have satisfied each objective and then start working at your level. This article categorizes your skill sets into the following areas:
  • Java Programmer
  • Java Applied Technologies
  • Java Web Technologies
  • Enterprise JavaBeans
  • Enterprise Architecture

Java Programmer

A Java programmer understands the basics of the syntax and semantics of the Java programming language. You must be proficient in object-oriented concepts, such as inheritance and polymorphism, as well as Java's specific notion of interfaces. You must understand Java exception handling and be able to implement your own custom exceptions.
Familiarize yourself with the Abstract Window Toolkit (AWT) and how to develop applications and applets. Understand the Event Delegation Model and how Graphical User Interface (GUI) objects pass event notifications to interested parties.
Pay attention to Java's implementation of its Collection classes (universal data structures and algorithms) and its basic input/output classes (such as Streams and Readers/Writers). Conclude your Java overview with a deep understanding of multi-threaded Java programming. Be sure to not only understand how to create a thread and execute it, but also to understand synchronization and object locks.
This overview describes two eight-week courses that I taught to prepare new Java students for certification. I outline all of these topics in my latest book, Java 2 Primer Plus, along with the topics covered in the "Java Applied Technologies" and "Java Web Technologies." (This is the first, last, and only plug for my book in this article; it was based off of four courses that I architected to evolve Java programmers to Java Developers, so I mention it only because of its relevance to this discussion.)
Once you have this information under your belt, take the Sun Certified Java Programmer exam. At the end of this program, you will have several certifications, each taken as specific skills are mastered. This is the best time to take the programmer certification. The information in the test is very specific, and you may forget it later and have to refresh yourself before the test. So take the exam while it is fresh in your mind!

Java Applied Technologies

Understanding the Java programming language is your starting point, but you must do something with it to solve real-world problems. To solidify your foundation, Java provides several core technologies that you should understand and be able to apply. The key technologies that I identify are:
  • Swing
  • JDBC
  • Network Programming
  • Remote Method Invocation (RMI)
  • XML
As an Enterprise Java Developer, you will not do a whole lot of GUI development, but Swing is among the fundamentals that you should understand. You should be able to use advanced Swing controls to build a GUI that can display and monitor your Enterprise framework. Not to mention that the basis of Swing's architecture will help you design strong enterprise architectures later; this includes the concept of separating your data from the presentation of your data, or in Swing terms, the "Separable Model View Architecture." The book that I am currently using to Swing is Java Swing, 2nd Edition.
Almost all enterprise applications talk to a database in the background. The method of communication is through the Java Database Connectivity API (JDBC). You need to understand the basis of the Structured Query Language (SQL) and how to use JDBC to connect to a database, execute queries, update data, remove data, etc. JDBC is so fundamental that I cannot emphasize its importance to you enough. An exhaustive reference for JDBC is the JDBC API Tutorial and Reference, Second Edition: Universal Data Access for the Java 2 Platform and a good streamlined overview can be found in Core Java 2: Volume II – Advanced Features (The latter is a good overall Java book that you might want to have on your shelf or add to your Safari virtual library.)
The mechanism for communicating between Java programs is through the java.net.Socket class. You will experience a couple iterations of network communication, but the place to start is the java.net package. Learn how to connect to a server and then how to implement your own server. Pay particular attention to receiving a connection from a client, passing that connection off to another thread for processing, and then listening for additional connections. You need to understand how to develop a high-volume multi-user server. As an example, you could write a chat server and chat client; this demonstrates this skill set nicely. Core Java 2: Volume II provides good information on both network programming as well as RMI.
Remote Method Invocation, or RMI, is the basis for Java distributed computing, and the foundation upon which J2EE builds. Although as an Enterprise Java developer you may never write RMI code directly, learning RMI serves two purposes:
  • Introduces you to distributed computing
  • Provides an understanding of the underlying communication infrastructure of your J2EE application server
Finally, J2EE relies heavily on XML, so it serves you well to understand how to manipulate it. Furthermore, as service-centric applications are being built on top of Web Services, XML becomes even more important, as it is the communication protocol that encapsulates messages being passed between components. The key things to understand here are SAX (Simple API for XML) parsing and the DOM (Document Object Model). A good understanding of these two concepts and Java's implementation through the Java API for XML Parsing (JAXP) will help you in the industry.
But for your own use, you may consider looking at JDOM, which is an open-source Java-centric approach to XML manipulation. My favorite Java XML book is Brett McLaughlin's Java and XML, 2nd Edition.
After you have completed the "Java Applied Technologies" objectives, you should get your Java Certified Developer certification (see the certification section of the reference guide for more information.)

Java Web Technologies

The next step in your journey is to understand Java's Web Technologies, namely Servlets and JavaServer Pages (JSP) and how they work together. It will help you to understand the history of dynamic Web page generation from the early days of CGI scripts to the latest JSP technologies.
Some books teach you JSP right out of the gate because it is easier to develop JSP files than it is to write Servlets, but I do not subscribe to this methodology. The reason is that learning JSP syntax shows you how to use a technology without properly understanding what it is doing. There are too many black boxes that your code passes through. Therefore, I strongly recommend that you become a good Servlet programmer first.
Focus on how to read information from a Web Browser, both through HTTP GETs and POSTs, and the process of building and sending a response back to the browser. Understand session management, forwarding and including requests to and from other Servlets, and how to implement Servlet Filters. Learn the lifecycle of a Servlet and the various security mechanisms that are built into the Servlet API to secure access to your Servlets. My favorite book in this arena is Jason Hunter's Java Servlet Programming, 2nd Edition.
Once you have a good understanding of Servlet technologies, then focus your attention on JSPs. Be sure to understand the following:
  • JSP syntax
  • JSP Scriptlets (although you will not use them in production code)
  • JSP built-in tags
  • Component-based JSP programming (using JavaBeans)
  • Building Custom Tag Libraries
  • Integrating Servlets and JSP components to build a Model-View-Controller web architecture
First understand how to use JSPs individually and finally combine them with Servlets to build a robust architecture with the focus on: Servlets with no embedded HTML and JSP files with no embedded Java. A good book in this area is JavaServer Pages, 2nd Edition.
Now is a good time to take the Web Component Developer certification exam; it will exercise your knowledge of these technologies.
Before leaving this topic, you might want to familiarize yourself with some of the pre-built and open-source web architectures. The main one used in the industry is Jakarta Struts, so it is a great starting point. There are some good Struts books, but the one that I keep handy is Programming Jakarta Struts.

Java 2, Enterprise Edition

J2EE combines a Servlet container (in which Servlets and JSP files execute) with an Enterprise JavaBean (EJB) container and a host for various services (such as transaction management, JDBC connection pooling, and Java Messaging Service (JMS) Servers). The first focus in J2EE has to be EJB. Be sure to understand how to implement and the differences between Stateless and Stateful Session Beans, Bean Managed and Container Managed Entity Beans, and Message Driven Beans. Learn how to compile these beans, write deployment descriptors for them, and finally deploy them to an application server. My favorite book for learning EJB is Monson-Haefel's Enterprise JavaBeans, 3rd Edition.
Next, turn your attention to using and configuring JMS Servers. Understand the publish-and-subscribe and point-to-point messaging models and how JMS Servers relate to their destinations (topics and queues.) Post messages to JMS destinations and create Message Driven Beans to respond to them. JMS is a fundamental technology that is applied to implementing Web Services. A book that I really like on JMS is Java Message Service, but it has been out for over two years, so you might consider the more recent Java Message Service API Tutorial and Reference: Messaging for the J2EE™ Platform.
Choosing an application server is a key to finding a good job; most J2EE jobs will require experience with one of the two market leaders: BEA's WebLogic and IBM's WebSphere. I personally do my J2EE-specific development work inside JBoss because of its ease of use, and then target my application at one of the two aforementioned servers. There is a lot of controversy around JBoss, but I think it is the best environment to learn J2EE development; you write your deployment descriptors by hand, reinforcing their underlying meaning (the important part) and then deployment is made incredibly simple (the deployment of an application is not core to your understanding of the technology, so do not complicate it at this point.)
Application Server specific books that you might want to look through include:

Enterprise Architecture

Understanding how to use the J2EE technologies is not enough to prepare you for your J2EE Architect Certification, you must first know how to use the technologies together effectively (design patterns) and how to articulate your designs to your peers (UML).
Design patterns demonstrate solutions that have already been defined for classes, or categories, of problems; when faced with a problem it is better to see if someone has already solved the problem before solving it again. Sun's Web site is full of J2EE design patterns, as is the book Core J2EE Patterns: Best Practices and Design Strategies.
UML has become the standard Enterprise Architecture language for expressing an architecture to other architects and to your development team. UML was originally developed by Rational Software and applied through the Rational Unified Process (RUP), which was an entire software engineering model. The book Building J2EE Applications with the Rational Unified Process demonstrates how to integrate the RUP and UML diagrams with J2EE concepts.
The last thing that you need to do before taking getting your Enterprise Architect Certification is to review for this difficult exam, programming assignment, and second exam (essay-based). Prentice Hall released a study guide for this exam: Sun Certified Enterprise Architect for J2EE Study Guide to help you.

Summary

This article has outlined a roadmap that you can follow to become an Enterprise Java architect. In retrospect, the reason that Enterprise Java architects demand a high salary is because they are required to know a whole lot of information! The reading list and topics that I outlined for you could easily take you a year or more of dedicated study to accomplish. It is probably one of the most difficult positions to grow into, but it is also one of the most rewarding.
I would recommend following this path and then working at whatever skill set level you happen to be in to gain experience while you learn additional skills. Before someone will hire you as an Enterprise Architect, you'll need experience in the industry, so consider this a three year goal: work in the Java industry and keep adding skills as time permits. Before you know it, you will be at the bleeding edge of enterprise Java knowledge!
It has been several years since I first published a roadmap to becoming an enterprise Java developer, so in this 2007 installment, I want to review our humble beginnings and then review the hot topics that you need to understand in today's ever evolving industry. Much of my original article is still valid, so in this installment will review and build from that base

Selasa, 18 Maret 2014

Tahukah Anda, Problem Masyarakat Jakarta?

Sumber dari 

http://evello.co.id/tahukah-anda--problem-masyarakat-jakarta?

Hari ini (Jumat 17/01/14) hampir semua media online memberitakan tentang kejadian banjir yang menimpa Jakarta. Tidak seperti banjir pada tahun 2013 yang sampai menyebabkan jatuhnya korban jiwa, banjir tahun 2014 lebih dapat diantisipasi, terutama setelah dilakukannya pengerukan beberapa sungai besar di Jakarta dan normalisasi waduk pluit, riario, melati, bojana tirta dan lain sebagainya. Tentu saja, banjir bukanlah satu-satunya persoalan yang dihadapi masyarakat Jakarta. Masih terdapat isu-isu lain yang tentu saja menarik perhatian masyarakat.
Dalam menjaring isu-isu yang beredar Evello sebagai tools Intelligent Tagging System (ITS) digunakan untuk menjaring isu-isu yang menjadi perhatian masyarakat. Proses penjaringan dilakukan dengan melakukan crawling terhadap beberapa media online dan sosial media yang dilakukan mulai 1 Oktober 2013 sampai dengan saat tulisan ini dibuat pada 17 Januari 2014 seperti pada ulasan berikut ini.
Gambar berikut ini memperlihatkan Real Time Monitoring (RTM) yang dilakukan oleh Evello System pada media online dan sosial media terhadap beberapa isu di DKI Jakarta, seperti Banjir, Macet, Kriminalitas, Sampah, Transportasi dan Tawuran. Hasil RTM tersebut adalah berikut:
Real Time Monitoring (RTM) Media Online untuk Isu Paling Populer di DKI Jakarta
Pada gambar terlihat bahwa pergerakan pemberitaan dan pembicaraan untuk beberapa isu seperti Banjir, Kemacetan, Kriminalitas terlihat fluktuatif disesuaikan dengan tema yang menarik pada saat itu. Dari grafik-grafik di atas, jika dilakukan konversi perhitungan untuk Average Mention per Day, Average % dan Total Mention Post adalah sebagai berikut:
Resume, Trend and Average (RTA) untuk Isu yang Populer di DKI Jakarta Berdasarkan Media Online
Sementara Total Mention Post (TMP) untuk media sosial dari tanggal 1 Oktober 2013 sampai dengan 17 Januari 2014 adalah 6711 posting dengan Urutan Banjir 2012, Macet 1649, Kriminalitas 1124, Transportasi 1081, Sampah 705 dan Tawuran 140 posting.
Resume, Trend and Average (RTA) untuk Isu yang Populer di DKI Jakarta berdasarkan Media Sosial
Dari tabel di atas terlihat bahwa isu banjir menempati tempat teratas baik di pemberitaan Media Online dan pembicaraan di Media Sosial. Pembicaraan tentang kemacetan menempati urutan kedua di Media Sosial dibandingkan pemberitaan di Media Online yang menempatkan isu Kriminalitas pada urutan kedua.
Data-data tersebut dapat diolah lebih lanjut secara otomatis pada Evello dengan menampilkan kembali dalam bentuk grafik batang dan pie seperti terlihat pada gambar berikut ini:
Average Mention Per Day untuk Isu di DKI Jakarta berdasarkan Media Online
Berdasarkan analisis Share Index yang dilakukan oleh Evello System pada Media Online, Isu-isu yang menjadi perhatian masyarakat DKI adalah seperti:
  1. Banjir – 30%
  2. Kemacetan – 25%
  3. Kriminalitas 17%
  4. Transportasi 16%
  5. Sampah – 11% dan
  6. Tawuran 2%
 Share Index untuk Isu Populer di DKI Jakarta Berdasarkan Media Online
Untuk masing-masing isu di atas, dapat diperoleh aspek-aspek lainnya berupa sentimen. Dalam hal ini, Evello System melakukan pemetaan sentimen positif untuk stakeholder yang bertanggung jawab terhadap penyelesaian berbagai isu diatas dan sentimen negatif untuk masing-masing isu tersebut. Berdasarkan grafik sentimen di atas, maka diperoleh data-data sebagai berikut:
Sentimen Positif untuk Isu Yang Populer di DKI Jakarta
Berdasarkan grafik sentimen di atas, maka diperoleh data-data sebagai berikut:
  1. Jokowi mendapatkan isu positif sebagai orang yang bertanggung jawab untuk menyelesaikan beragam isu di DKI Jakarta dibandingkan dengan SBY.
  2. Pemerintah Pusat dianggap memiliki peran yang lebih dalam penanganan isu-isu di DKI Jakarta di bandingkan peran Pemda DKI
Sementara untuk grafik sentimen negatif, dapat diperoleh data-data sebagai berikut:
  1. Semua isu seperti Banjir, Macet, Kriminalitas, transportasi dan Sampah (kecuali tawuran) disebabkan karena adanya salah perencanaan.
  2. Hanya sedikit aspek negatif Salah Penanganan terjadi pada isu Banjir dan sampah.
  3. Terdapat sentimen negatif pada isu transportasi, yaitu Salah Urus Transportasi.
Sentimen Negatif untuk Isu Yang Populer di DKI Jakarta

Kamis, 25 Juli 2013

jodoh pasti bertemu

Andai engkau tahu betapa ku mencinta
Selalu menjadikanmu isi dalam doaku
Ku tahu tak mudah menjadi yang kau pinta
Ku pasrahkan hatiku, takdir kan menjawabnya

Jika aku bukan jalanmu
Ku berhenti mengharapkanmu
Jika aku memang tercipta untukmu
Ku kan memilikimu, jodoh pasti bertemu

Andai engkau tahu betapa ku mencinta
Selalu menjadikanmu isi dalam doaku
Ku tahu tak mudah menjadi yang kau pinta
Ku pasrahkan hatiku, takdir kan menjawabnya

Jika aku bukan jalanmu
Ku berhenti mengharapkanmu
Jika aku memang tercipta untukmu
Ku kan memilikimu, jodoh pasti bertemu

Jika aku (jika aku) bukan jalanmu
Ku berhenti mengharapkanmu
Jika aku memang tercipta untukmu
Ku kan memilikimu

(jika aku bukan jalanmu)
Ku berhenti mengharapkanmu
Jika aku memang tercipta untukmu
Ku kan memilikimu, jodoh pasti bertemu

" Memilih Setia "

T'lah banyak cara Tuhan menghadirkan cintaMungkin engkau adalah salah-satunyaNamun engkau datang di saat yang tidak tepatCintaku telah dimiliki…

Inilah akhirnya harus kuakhiriSebelum cintamu semakin dalamMaafkan diriku memilih setiaWalaupun ku tahu cintamu lebih besar darinya

Maafkanlah diriku tak bisa bersamamuWalau besar dan tulusnya rasa cintamuTak mungkin untuk membagi cinta tulusmuDan aku memilih setia…

Inilah akhirnya, harus aku kuakhiriSebelum cintamu semakin dalamMaafkan diriku memilih setiaWalaupun ku tahu cintamu lebih besar darinya

Seribu kali logika ku untuk menolakTapi ku tak bisa bohongi hati kecilkuBila saja diriku ini masih sendiriPasti ku memilih dan memilih mu

Inilah akhirnya, harus aku kuakhiriSebelum cintamu semakin dalamMaafkan diriku memilih setiaWalaupun ku tahu cintamuWalaupun ku tahu cintamu lebih besar darinya

Kamis, 27 Juni 2013

Tier Level pada Data Center Menurut TIA 942 (Telecommunication Industry Association)

DATA CENTER
Definisi Data Center
ü  . . . komponen penting dari infrastruktur yang mendukung Internet dan perdagangan digital Juga sektor komunikasi elektronik. Pertumbuhan sektor-sektor ini memerlukan infrastruktur yang handal karena. gangguan dalam layanan digital dapat memiliki konsekuensi ekonomi yang signifikan.
ü  Data Center adalah repositori terpusat, baik fisik maupun virtual, untuk manajemen penyebaran penyimpanan data dan informasi berkaitan dengan yang dikelola sesuai dengan keperluan  atau kepentingan suatu organisasi atau perusahaan.
Sekilas tentang Data Center
Hampir, setiap perusahaan memiliki satu atau lebih Data Center.
Beberapa telah berevolusi dengan cepat untuk mengakomodasi lingkungan aplikasi enterprise dengan memanfaatkan beragam platform sistem operasi atau perangkat keras.
Evolusi telah menghasilkan lingkungan yang kompleks dan berbeda yang mahal untuk dikelola dan dipelihara.

Enterprise Data Center

Bagan 1. Enterprise Data Center
Gambar menyajikan blok bangunan berbeda yang digunakan dalam jaringan perusahaan yang khusus dan menggambarkan lokasi Data Center dalam arsitektur tersebut.

Blok bangunan dari  jaringan perusahaan yang khusus ini,  yaitu:
   ü  Jaringan Komputer Lokal
   ü  WAN
   ü  Remote akses
   ü  Internet server farm
   ü  Extranet server farm
   ü  Intranet server farm
Contoh aplikasi enterprise, diantaranya:
ü  Customer Relationship Management (CRM)
ü  Enterprise Resource Planning (ERP)
ü  Supply Chain Management (SCM)
ü  Sales Force Automation (SFA)
ü  Order Processing (OP)
ü  Electronic Commerce (E-Commerce)
Fungsi Data Center
Berdasarkan fungsinya, data center dibagi menjadi 2  (dua) kategori umum yaitu:
1.       Internet Data Center: hanya untuk mendukung aplikasi terkait dengan Internet saja, biasanya dibangun dan dioperasikan oleh service provider atau perusahaan yang memiliki model bisnis berdasarkan pada Internet commerce.
2.       Corporate/Enterprise Data Center : mendukung semua fungsi yang memungkinkan berbagai model bisnis berjalan pada layanan Internet, intranet, dan keduanya.

Tujuan Data Center
Manfaat yang diberikan oleh Data Center termasuk  di dalamnya tujuan yang berorientasi bisnis tradisional seperti:
ü  Mendukungan untuk operasi bisnis sepanjang waktu (ketahanan) dan
ü  Menurunkan total biaya operasi dan pemeliharaan yang dibutuhkan untuk mempertahankan fungsi bisnis (total biaya kepemilikan).
ü  Waktu Development yang lebih cepat
ü  Konsolidasi Sumberdaya Komputasi
 Tujuan-tujuan bisnis tersebut menghasilkan sejumlah inisiatif teknologi informasi (TI), antara lain :
ü  Keberlanjutan Usaha (Bussiness Continuity)
ü  Peningkatan keamanan Data Center
ü  Aplikasi, server, dan konsolidasi Data Center
ü  Integrasi aplikasi.
       Apakah client/server dan multitier (n-tier), atau layanan web yang terhubung  dengan aplikasinya
ü  Konsolidasi tempat penyimpanan (storage)
Kriteria Perancangan Data Center
ü  Ketersediaan  (Availability)
ü  Skalabilitas  (Scalability)
ü  Keamanan  (Security)
ü  Kinerja (Performance)
ü  Pengelolaan (Manageability)
Komponen Utama Data Center
ü  Kapasitas Catu Daya (power capacity)
ü  Kapasitas Pendingin (cooling capacity)
ü  Pengkabelan (cabling)
ü  Pengaturan Suhu dan Kelembaban (temperature and humidity control)
ü  Sistem pengaman kebakaran (fire and smoke system)
ü  Keamanan Fisik (physical security)
ü  Penataan ruang rak dan lantai (rack space and raised floor)

Tier Level pada Data Center
Aspek Penilaian Tier Level Data Center
ü  Aspek Umum pada Data Center
ü  Telekomunikasi
ü  Arsitektural dan Struktur
ü  Elektrik
ü  Mekanikal

Jumlah Tingkatan
Menurut TIA 942 (Telecommunication Industry Association).
ü  Terdapat 4 (empat) tingkatan/tier dalam perancangan data center yang setiap tier-nya menawarkan tingkat availabilitas yang berbeda, disesuaikan dengan kebutuhan suatu data center.
ü  Sesuai standarisasi, tier level yang elegible adalah tier level terendah dari setiap aspek; namun di lapangan lebih populer penggunaan aspek umum, sebagaimana Tabel dibawah ini

Tier Untuk Aspek Umum Pada Data Center
ü  Tier 1 (Basic)
ü  Tier 2 (Redundant Components)
ü  Tier 3 (Concurently Maintainable)
ü  Tier 4 (Fault Tolerance)
Tabel 1, Tabel Kriteria Tier Data Center menurut TIA 942 (Telecommunication Industry Association).
 Interaksi Aplikasi Client/Server dan n- Tier

Bagan 2: (a) Client Server; (b) n-tier

Istilah Tier Pada Implementasi Aplikasi
Client-Server dan n-Tier Pada Implementasi Aplikasi
ü  Perubahan yang paling mendasar  thick client dan single-server model dimulai ketika aplikasi berbasis web pertama kali muncul. Aplikasi berbasis web bergantung pada standar antarmuka dan format pesan dimana aplikasi lebih mudah untuk berbagi.
ü  HTML dan HTTP menyediakan kerangka kerja standar yang memungkinkan klien umum seperti browser web untuk berkomunikasi dengan aplikasi umum selama mereka menggunakan Web Server  untuk fungsi presentasi.
ü  HTML menggambarkan bagaimana client harus membuat data; HTTP adalah protokol transport  yang digunakan untuk membawa data HTML;
ü  Microsoft Internet Explorer, FireFox, Chrome, Opera adalah contoh Clien (Web Browser);
ü   Apache web Server, Websphere,Bealogic, Glashfish , dan Microsoft Internet Information Server (IIS) adalah contoh dari Web Server.
ü  Migrasi dari klasik client/server ke arsitektur berbasis web menggambarkan penggunaan thin client (web browser), web server, server aplikasi, dan database server.
ü  Web Browser berinteraksi dengan Web Server dan server aplikasi, dan web server berinteraksi dengan server aplikasi dan database server.
ü  Perbedaan fungsi ini  didukung oleh server disebut sebagai tier, yang selain untuk klien tier, juga sesuai dengan model n-tier.



Model N-Tier 

Bagan 3. Contoh N-Tier

ü  Model n-tier menggunakan thin client dan web browser untuk mengakses data dalam berbagai cara. Sisi server model n-tier ini dibagi menjadi area fungsional yang berbeda termasuk web, aplikasi, dan database server.
ü  Model n-tier tergantung pada arsitektur web standar dimana format web browser merepresentasikan informasi yang diterima dari Web Server . Sisi server dalam arsitektur web terdiri dari beberapa server dan berbeda yang secara fungsional terpisah.
ü  Model n-tier dapat berupa client dan web server, atau client, web server, dan server aplikasi; atau client, web, aplikasi, dan server database.
ü  Model ini lebih terukur dan dikelola, dan meskipun lebih kompleks dibandingkan dengan model client/ server klasik, memungkinkan lingkungan aplikasi untuk berkembang ke arah lingkungan komputasi terdistribusi.
ü  Model n-tier menandai langkah penting dalam evolusi dari komputasi terdistribusi.