From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: X-Spam-Status: No, score=-0.0 required=5.0 tests=BAYES_20 autolearn=ham autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 103376,3d892c006426c5e6 X-Google-Attributes: gid103376,public X-Google-ArrivalTime: 2003-04-24 11:10:00 PST Path: archiver1.google.com!postnews1.google.com!not-for-mail From: jimmaureenrogers@worldnet.att.net (Jim Rogers) Newsgroups: comp.lang.ada Subject: Re: Tools vs. Parts Date: 24 Apr 2003 11:10:00 -0700 Organization: http://groups.google.com/ Message-ID: <82347202.0304241009.55d9745d@posting.google.com> References: <6LidnfIK-pvMZjqjXTWcog@gbronline.com> NNTP-Posting-Host: 209.194.156.4 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8bit X-Trace: posting.google.com 1051207800 26036 127.0.0.1 (24 Apr 2003 18:10:00 GMT) X-Complaints-To: groups-abuse@google.com NNTP-Posting-Date: 24 Apr 2003 18:10:00 GMT Xref: archiver1.google.com comp.lang.ada:36491 Date: 2003-04-24T18:10:00+00:00 List-Id: Wesley Groleau wrote in message news:<6LidnfIK-pvMZjqjXTWcog@gbronline.com>... > A little imagination and analogy: > [snip] > (I could drag this on for a long time .....) > > I'm sure we all get the point, no matter which > side of personality spectrum we're on. But > just in case someone needs a hint, look at the > initials of all the names. > > (or make up an acronym for "carb off the shelf") The old "buy or build" issue has been around for a long time. In recent years the issue has become more important to U.S. Department of Defense projects because the Government officials have legislated the use of Commercial Off The Shelf products to save cost. The decision logic assumes that a product good enough for industry is good enough for the military. In some cases the logic holds, and COTS products are appropriate. There are other cases where the logic fails dramatically. COTS hardware has never been built to the usage specifications required by the military. These specifications include a very wide range of temperatures, humidity, and altitude. They also include resistance to shock and vibration beyond commercial standards. Finally, military equipment must be sealed against NBC exposure. (NBC stands for Nuclear, Biological, and Chemical). COTS software is very useful when used the same way it is in industry. COTS software is inappropriate in mission critical systems. Military systems tend to have lifetimes counted in decades, while commercial software tends to have lifetimes counted in months. This means that a military system built upon COTS software will be unsupported by the vendor within 18 to 24 months, while it must continue to operate for 30 years. COTS products also present a major challenge in reliability predictions. Few commercial vendors will share reliability data about their products, if they even keep such data. One of the factors that should be used to choose between COTS and custom products is reliability. A cheap initial COTS purchase may result in high maintenance and risk costs if it exhibits low reliability. Conversely, an expensive initial purchase of a custom product with high reliability can result in a low overall cost of ownership. Jim Rogers