NetCentric Computing Overview 2110472 Computer Networks Natawut Nupairoj

Net-Centric Computing Overview 2110472 Computer Networks Natawut Nupairoj, Ph. D. Department of Computer Engineering Chulalongkorn University

“Network is Computer. ” -- Sun Microsystems. Net-Centric Computing Overview Natawut Nupairoj, Ph. D.

What is Net-Centric Computing ? “Distributed environments where applications and data are exchanged among peers across a network on as as-needed basis. ” l Applications on distributed environments ? l l l more than one machine / one user. multiple platform is possible. How can we exchange data ? l standard data formats. Net-Centric Computing Overview Natawut Nupairoj, Ph. D.

What is Net-Centric Computing ? “Distributed environments where applications and data are exchanged among peers across a network on as as-needed basis. ” l Are you my peers ? l l security issues. How soon is as-needed ? l l Real-time / batch data exchanging. Push / Pull. Net-Centric Computing Overview Natawut Nupairoj, Ph. D.

What is NCC, really ? l l l l Information system (applications). Multiple machines. Over the network. Seamlessly integrated. Using standard data formats. There are some securities. Example, anyone ? Net-Centric Computing Overview Natawut Nupairoj, Ph. D.

Why NCC ? l Stand alone system is not enough l l Collaborative among users l l Share disks, tapes backup, printers. Centralized management l l l All works are workflows by nature. Pool of resources l l Do you know “Starcraft” ? Application codes. Data consistencies. And much more… Net-Centric Computing Overview Natawut Nupairoj, Ph. D.

What will be taught in this class ? l Network application architectures and services l l l A touch on “here-and-there”. Application-level protocols. Network-level protocols (TCP/IP) – very minimal. Net-Centric Computing Overview Natawut Nupairoj, Ph. D.

What will NOT be taught in this class ? l l l How to write a Java (or other languages) program. How to create a web page. How to write a network game l l You should study Distributed System. Low-level protocols (e. g. physical layer). Net-Centric Computing Overview Natawut Nupairoj, Ph. D.

What should you know to enjoy this class ? l Use Internet for studying a lot l l Search engine. Programming. HTML. Database skills. Net-Centric Computing Overview Natawut Nupairoj, Ph. D.

The Revolution of NCC l “Tier”-based paradigms l l l Where the codes (or logics) are ? Presentation / Business / Data logics. Types of NCC architectures l l One-tier. Client/server (two-tier). Three-tier. Multi-tier. Net-Centric Computing Overview Natawut Nupairoj, Ph. D.

Single-Tier Architecture l Mainframe with “dumb” terminals. l Pros: Business Data Presentation l l Cons: l l Net-Centric Computing Overview Good security and management. Difficult to improve. Vendor “locked-in”. Natawut Nupairoj, Ph. D.

Client/Server Architecture l Database server with fat clients (PCs). l Pros: l l Cons: l l l Net-Centric Computing Overview Cheap and simple. Difficult to manage. Performance. Security problems. Natawut Nupairoj, Ph. D.

Three-Tier Architecture l Database + Web server with Browsers (Thin clients). B l Pros: l DB Svr Web Svr l B l l B Net-Centric Computing Overview Cheap and simple. Good performance. Simple to manage with good security. Cons: l Slightly difficult to develop. Natawut Nupairoj, Ph. D.

Multi-Tier – The Current Trends l Database + App + Web server with Browsers. B l App Svr DB Svr App Svr Pros: l Web Svr App Svr Net-Centric Computing Overview B l More flexible. Cons: l More expensive. B Natawut Nupairoj, Ph. D.

Basic Terminologies l Internet l l Intranet l l l Anyone don’t know ? Very important. Internal applications. Extranet l l Integrating with external parties. VPN. Net-Centric Computing Overview Natawut Nupairoj, Ph. D.

E-everything – Buzz Words l l l l E-Commerce. E-Business. E-Service. E-Learning. E-Billing. E-Government. EAI (Enterprise Application Integration). Net-Centric Computing Overview Natawut Nupairoj, Ph. D.

A-2 -Z l l l From who To who. B 2 C. B 2 B. B 2 E. G 2 G. B 2 G. Net-Centric Computing Overview Natawut Nupairoj, Ph. D.

Content Delivery l Client “Pull” l l Requested by client to get information. Usually imply manual control. “Smart pull”. Server “Push” l l Subscribe (or register) and update. Utilize better network bandwidth. Net-Centric Computing Overview Natawut Nupairoj, Ph. D.

Net-Centric Services l Locator Services l l l Data Repository Services l l User profiles (Database). Security Services l l Naming service (DNS). Directory service (LDAP). Authentication service (Login). And more … Net-Centric Computing Overview Natawut Nupairoj, Ph. D.

Summary l l NCC Architectures. Basic Terminologies. Net-Centric Computing Overview Natawut Nupairoj, Ph. D.

References l l l S. Tilley et al. , “The State of Net-Centric Computing in Early 2001”, The Proceeding of the 3 rd International Workshop in Net-Centric Computing, May 2001, pp. 57 -61. S. Tilley, “The Era of Net-Centric Computing”, SEI Interactive, Vol. 1, No. 1, June 1998. R. Peacock, “Distributed Architecture Technologies”, IEEE IT Professional, May/June 2000, pp. 58 -60. Net-Centric Computing Overview Natawut Nupairoj, Ph. D.