Fred I assume that you question is to be interpreted as "Would someone be able to tell me whether NetView FTP uses hardware or software compression?"
- According to http://www-01.ibm.com/common/ssi/cgi-bin/ssialias?infotype=dd&subtype=sm&appname=ShopzSeries&htmlfid=897/ENUS5685-108 NetView FTP for MVS V2R2.1 is probably what you have. I downloaded some of the product manuals and I see that, assuming you are not using the OSI interface, your NetView FTP will be using the VTAM API. By finding references to compression in various of the manuals, it becomes evident that the three types of compression used by NetView FTP mean the following: - NONE - No compression is used - actually the easiest to work out! - SNA - SNA-type compression is used which, anywhere else in the world would be described as "Run-Length Encoding (RLE) or Compaction" - ADAPT - Adaptive compression is used - strong hints that the good gentlemen Lempel, Ziv and Welch were the authors of the technique Nothing is said in the NetView FTP manuals about whether there is any use of the hardware capability to assist with compression which I would tend to assume means that there is no use of hardware. Note that, if hardware were used, there would need to be a statement somewhere in the documentation regarding the appropriate processor I happen to have some presentation notes on when this hardware capability became available and the notes are as follows: <quote> Note: Hardware compression is available with certain ES/9000 models from February 1993. It also requires a minimum MVS level of SP V4R3 with PTF UY91011. </quote> What I think has happened is that the IBM developers in one of those Baden-Württemberg locations implemented this pair of compression options in their product without having checked with their colleagues in the Research Triangle Park location whether or not the product managing the API they were using was going to set about implementing the self-same pair of compression options in the very near future thus making their efforts essentially pointless! Thus what I actually recommend is that you abandon using the NetView FTP options, that is specify "NONE", and arrange for VTAM to do what you were thinking of asking NetView FTP to do. I realise this is not very patriotic but may be more sensible. What I can now say is that the VTAM mechanisms *do* use the hardware capability where it seems appropriate. Furthermore there is a VTAM start option, CMPMIPS, which must be set in order to indicate when hardware compression "switches in". I'm pretty sure there would need to be specification of a similar parameter by NetView FTP if it were to be capable of using hardware compression. I'm sending you my presentation on the topic which I happen to have converted to a document from a GML form. It is intended to cover everything you need to know. - I find this technique of starting the question with "Anyone know ...", already an abbreviation of "Does anyone know ...", most curious! In many cases, such as this one, a perfectly valid reply, answering the question fully, would be "I imagine the developers of the product would know."! - Chris Mason On Wed, 2 Nov 2011 11:28:44 +0100, Fred Schmidt <fred.schm...@db.com> wrote: >Anyone know whether Netview FTP uses hardware or software compression? > >Regards, Fred Schmidt ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
