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=-1.9 required=5.0 tests=BAYES_00 autolearn=unavailable autolearn_force=no version=3.4.4 X-Received: by 10.58.22.166 with SMTP id e6mr11321930vef.6.1397843938585; Fri, 18 Apr 2014 10:58:58 -0700 (PDT) Path: border2.nntp.dca.giganews.com!m5no3095181qaj.1!news-out.google.com!du2ni12275qab.0!nntp.google.com!border1.nntp.dca.giganews.com!nntp.giganews.com!local2.nntp.dca.giganews.com!news.giganews.com.POSTED!not-for-mail NNTP-Posting-Date: Fri, 18 Apr 2014 12:58:58 -0500 Date: Fri, 18 Apr 2014 13:58:57 -0400 From: Alan Browne User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.9; rv:24.0) Gecko/20100101 Thunderbird/24.4.0 MIME-Version: 1.0 Newsgroups: comp.lang.ada Subject: Re: Heartbleed References: <1ljwj8f.1wqbhvuabsdw1N%csampson@inetworld.net> <51c7d6d4-e3be-44d5-a4ce-f7e875345588@googlegroups.com> <%J32v.70539$kp1.45343@fx14.iad> In-Reply-To: Message-ID: X-Usenet-Provider: http://www.giganews.com X-Trace: sv3-z1X0t4+PaWraUSX+ML3vn9IIm256W9/Vr5+RgBITb5PB7IenuhiAkJNbR79V3hINQ7FfCX4udFfV2hN!IJFApUxEghePbTd0iiM3S1q2J5d6Xqe4lTBPuoChnFo8iga+UV+a6ISrDy43N3JTJIsrEtZVZA== X-Complaints-To: abuse@giganews.com X-DMCA-Notifications: http://www.giganews.com/info/dmca.html X-Abuse-and-DMCA-Info: Please be sure to forward a copy of ALL headers X-Abuse-and-DMCA-Info: Otherwise we will be unable to process your complaint properly X-Postfilter: 1.3.40 X-Original-Bytes: 4700 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: quoted-printable Xref: number.nntp.dca.giganews.com comp.lang.ada:185810 Date: 2014-04-18T13:58:57-04:00 List-Id: On 2014.04.12, 18:01 , Yannick Duch=C3=AAne (Hibou57) wrote: > Le Sat, 12 Apr 2014 06:58:29 +0200, Shark8 a= > =C3=A9crit: > >>> BTW, once you have people exposed to type safe programming, then mayb= e >>> you can introduce them to Ada for the large projects. One of the majo= r >>> revelations for me over Heartbleed was seeing people discuss the need= >>> for a safer language and immediately jump to languages like Java. >> >> Hm, good point. >> Ada has some *REALLY* good features when it comes to >> programming-in-the-large -- the YF-22 integration is astounding: >> 12 major avionics subsystems, across 650 Ada modules containing >> millions of lines of code, coded in 8 geographically distinct >> locations, took *three days!* >> >> Source: http://archive.adaic.com/docs/present/engle/comments/tsld033.h= tm > > While Ada certainly played an important role in this success story, > another as much important role was certainly humans=E2=80=A6 how did th= ey > communicate between each others? I mean, what documentation techniques > and systems was used? Was the style guide(s) homogeneous or > heterogeneous? Did they used some kind of maps to handle the big lines > before diving into the details? > > I would enjoy a lot to know the answers to these questions. Ada is an element to the described success. Before a line of code is=20 written, requirements and specs must be written and ICD's agree'd upon;=20 many, many, many details need to be agreed to before software code=20 design begins. Also, databuses have evolved tremendously - reducing the wiring and=20 eliminating often bizarre timings on board aircraft/weapons systems and=20 making everyone use similar data types and structures throughout. Further, back in the 80's, the internet and e-mail were not yet common=20 as a means to sharing requirements, specs, test plans and ICD's. Now=20 such can be edited by teams in realtime w/o worrying about which copy of = the Word file is up to date - everyone sees one single evolving copy no=20 matter where and when they are. (I recall our one of nav systems integrated on a USAF aircraft where it=20 had to output waypoint and position data in different formats to=20 different systems over the same databus (using different A-429 labels).=20 But in one case two destination systems used the same data label but=20 different representations of position (semi-circles for one of them and=20 radians for the other IIRC). Ugly solution: the LSBit of each lat/long=20 pair (separate labels) was set to a 0 or 1 to distinguish which format.=20 The target systems would use that 'data' bit to accept or ignore the=20 data. (The 2 bit sign matrix having been used (wrongly) to signal some=20 other state)). It only took a conference call to make the ICD change. But down the=20 pike, when our system and their systems were integrated into other=20 aircraft, we and they had to change code again and again and again for=20 each new integration. Imagine the above for many dozen parameters on similar data buses ... --=20 "Big data can reduce anything to a single number, but you shouldn=E2=80=99t be fooled by the appearance of exactitude." -Gary Marcus and Ernest Davis, NYT, 2014.04.07