Slide 1Slide 2Slide 3Slide 4Slide 5Slide 6Slide 7Slide 8Slide 9Slide 10Slide 11Slide 12Slide 13Slide 14Slide 15Slide 16Slide 17Slide 18Slide 19Slide 20Slide 21Slide 22Slide 23Slide 24Slide 25Slide 26Slide 27Slide 28Slide 29Slide 30Slide 31Slide 32Slide 33Slide 34Slide 35Slide 36Slide 37Slide 38Slide 39Slide 40University of Southern CaliforniaCenter for Systems and Software EngineeringNDI and Services-Based Software Development ProcessSupannika KoolmanojwongPresented by Marilee Wheaton2010University of Southern CaliforniaCenter for Systems and Software EngineeringOutline•Non Developmental Item (NDI)•Net-Centric Services (NCS)•What are in the process?2@USC CSSEUniversity of Southern CaliforniaCenter for Systems and Software EngineeringWhat is NDI?•Non-Developmental Item–an item that is previously developed and available to use. –commercial-off-the-shelf, open source product, reuse library and customer-furnished package.–2 kinds of NDI•Application NDI : MS office•System NDI: MySQL–Related terms•COTS, GOTS, ROTS, •Reuse Code, Reuse library, Customer-furnished package 3@USC CSSEUniversity of Southern CaliforniaCenter for Systems and Software EngineeringCommon NDIs in CSCI577•Application-NDI–MS office, WordPerfect–OCR software–Joomla, Drupal, Wordpress–Coldfusion, Dreamweaver•System-NDI–Language: PHP, C++, Java, –Database: MySQL–Server: Apache–Others: Java Libraries11/02/2009 4@USC CSSEUniversity of Southern CaliforniaCenter for Systems and Software EngineeringWhat is COTS ? (1/2)•Commercial-off-the-shelf (COTS) definition by SEI–A product that is•Sold, leased or licensed to the general public.•Offered by a vendor trying to profit from it.•Supported and evolved by the vendor, who retains the intellectual property rights.•Available in multiple copies.•Used without internal modification by a consumer.•Source code may or may not be available.•No longer a COTS if the source code is modified internally511/02/2009 @USC CSSEUniversity of Southern CaliforniaCenter for Systems and Software EngineeringWhat is COTS? (2/2)•Can be tailored or extended using–An application programming interface (API).–Tailoring options•Graphical interface.•Parameter based interface.•Programmable interface.•Usually periodic releases with feature growth.•Commercial NDI products have a new release about every 10 months, and that old releases are supported by the vendor for about 3 releases. •Older versions eventually become obsolete.611/02/2009 @USC CSSEUniversity of Southern CaliforniaCenter for Systems and Software EngineeringCOTS Advantages and Disadvantages711/02/2009Advantages •Available now, earlier payback •Avoids expensive development & maintenance•Predictable license costs & performance•Rich in functionality•Broadly used, mature technology•Frequent upgrades often anticipate organization’s needs•Dedicated support organization•Hardware/software independence•Tracks technology trendsDisadvantages•Licensing and procurement delays•Up front license fees•Recurring maintenance fees•Reliability often unknown/ inadequate•Unnecessary features compromise usability, performance•Functionality, efficiency constraints•No control over upgrades/maintenance •Dependency on vendor•Integration not always trivial; incompatibilities among different COTS•Synchronizing multiple-vendor upgrades@USC CSSEUniversity of Southern CaliforniaCenter for Systems and Software EngineeringLessons Learned Using NDI (1/6)•Problems with vendors–Vendors promise and don’t deliver–Products don’t work as advertised–Don’t assume a quantity discount, negotiate price upfront•Need for flexibility in defining requirements–Distinguish between essential and negotiable requirements. Be flexible where you can.–What we did right - spent 14 out of a total of 22 months iterating between requirements, business processes and the marketplace–If you can bend your requirements, NDI is cheaper. Otherwise you’re better off with custom developed. (Not all projects may be flexible)811/02/2009 @USC CSSEUniversity of Southern CaliforniaCenter for Systems and Software EngineeringLessons Learned Using NDI (2/6)•Importance of operational demos–Spend a lot of time in detailed performance demonstrations with real users. –Up-front time is critical. That’s when you have leverage with vendors. Once you buy their product, they are a lot less willing to help out.•Assessment of specific attributes–Projects (COCOTS), in the past have expressed regret that they did not spend more time assessing portability, inter-component compatibility, flexibility (of user interface), and installation ease.911/02/2009 @USC CSSEUniversity of Southern CaliforniaCenter for Systems and Software EngineeringLessons Learned Using NDI (3/6)•Life-cycle issues–Supportability of NDI viewed as a major issue for safety-critical systems–Out of service is a critical problem•contractor purchased source code and will maintain NDI software–Projects, in past have expressed the view that NDI saved money during development but shifted costs to operational side of the life cycle–On-line software maintenance•How do you upgrade systems once they are in place and operating?1011/02/2009 @USC CSSEUniversity of Southern CaliforniaCenter for Systems and Software EngineeringLessons Learned Using NDI (4/6)•Life Cycle Issues (Upgrading)–What is an effective strategy for upgrading? Products reach end of life in two years.•Freeze and redo the system in 10 years?•Incorporate all versions from all vendors whenever they come out?•Refresh every 2 years?•Refresh a selected set of components every 2 years?–Should have an environment set up so you can load new versions onto the existing configuration and decide whether or not to upgrade.–Look at the entire life cycle realistically - not just development1111/02/2009 @USC CSSEUniversity of Southern CaliforniaCenter for Systems and Software EngineeringLessons Learned Using NDI (5/6)•NDI integrator experience–Important that they have experience integrating NDI.–Look carefully at their credentials. They will oversell themselves•Product maturity–Never use an untried OS–Maturity of the software was very important in NDI selection–If you have a safety-critical system, you don’t want state-of-the-art NDI1211/02/2009 @USC CSSEUniversity of Southern CaliforniaCenter for Systems and Software