Re: ISA 2004: Web Publishing disabling HTTP Compression

From: Wayne Berry (wayne_at_berryintl.com)
Date: 09/21/04

  • Next message: Adina Hagege [MSFT]: "Re: September 22 Chat: ISA Server 2004 Enabling Remote Client (VPN) Access" 
    Date: Tue, 21 Sep 2004 15:02:44 -0700

    What is Server Publishing? Either way you should be able to use XCompress
    for ISA

    -Wayne

    "Michael J. Carter" <michael@volcanictech.com> wrote in message
    news:OkTuVHCoEHA.744@TK2MSFTNGP10.phx.gbl...
    > Wayne, thanks for the confirmation. I had a feeling that was the case.
    >
    > Unfortunately, I can't use Server Publishing because I need to publish
    > multiple web servers on a single IP.
    >
    > I just seems kind of dumb to disable this. It would have been nice if they
    > mentioned this anywhere in their documentation.
    >
    > Thanks again.
    >
    > "Wayne Berry" <wayne@berryintl.com> wrote in message
    > news:ODekNvBoEHA.3900@TK2MSFTNGP10.phx.gbl...
    > > Michael,
    > >
    > > Basically compression doesn't work with ISA 2004. ISA 2004
    > >
    > > - Strips the compression header when the browser sends it, preventing
    the
    > > web server from "knowing" that the client supports compression
    > > - Doesn't Cache Compressed Responses
    > > - Doesn't Send Compressed Responses
    > >
    > > We (XCache Technologies http://www.xcache.com) write a compression
    filter
    > > for ISA 2000 and are working on a Compression filter for ISA 2004. It
    > > will:
    > >
    > > - Ask the web server for a compressed response.
    > > - Enable ISA 2004 to cache that response
    > > - Send a compressed response to the browser when the browser asks for
    it.
    > >
    > > -Wayne
    > >
    > >
    > > "Michael J. Carter" <michael@volcanictech.com> wrote in message
    > > news:uRmeKfBoEHA.3876@TK2MSFTNGP15.phx.gbl...
    > >> I'm using ISA 2004 and publishing internal web servers using Web
    > > Publishing.
    > >> I have enabled HTTP Compression (IIS6) on these sites, and everything
    > > works
    > >> if I access the server internally (directly).
    > >>
    > >> However, external clients that go through ISA are not getting HTTP
    > >> Compression.
    > >>
    > >> I did some experiments and this is what I found out:
    > >>
    > >> I created a test page on my internal server that dumps the headers. If
    I
    > >> access the site internally, I see this header:
    > >>
    > >> Accept-Encoding: gzip, deflate
    > >>
    > >> And all is well.
    > >>
    > >> However, if I access it from an external site, the header is no longer
    > >> there.
    > >>
    > >> I then created a simple Web Filter and installed it on the ISA Server.
    > > This
    > >> filter simply logs the Accept-Encoding header during the
    PREPROC_HEADERS
    > >> notification. The logs show that the Accept-Encoding header is present.
    > >>
    > >> Therefore, somewhere between the time my filter executes and ISA
    > > dispactches
    > >> the request to my web server, the Accept-Encoding header is stripped. I
    > >> understand that HTTP Filtering of the response body and HTTP
    compression
    > >> don't mix. However, I have disabled every Web Filter (except the one I
    > >> added) and I'm still seeing this problem.
    > >>
    > >> Is this normal behavior?
    > >>
    > >> Am I going to have to implement HTTP Compression in my filter and not
    use
    > >> the one built in to IIS 6?
    > >>
    > >> Oddly, I found this quote on Microsoft site:
    > >>
    > >
    http://www.microsoft.com/technet/prodtechnol/isa/2004/plan/httpfiltering.mspx
    > >>
    > >> Q. Can I cache compressed content?
    > >> A. In a Web publishing scenario, ISA Server allows the traversal
    of
    > >> compressed responses from the Web server to the client, if the client
    > > sends
    > >> an Accept-Encoding header indicating that it will accept compressed
    > > content.
    > >> However, compressed content will not be cached. Note that ISA Server
    does
    > >> not support traversal of compression responses in a forward proxy
    > > scenario,
    > >> and does not support inspection of compressed response bodies in any
    > >> direction.
    > >>
    > >>
    > >>
    > >>
    > >> So it appears that this is supposed to work. What am I missing here?
    > >>
    > >> BTW: I disabled HTTP Caching, and it is still not working.
    > >>
    > >> Michael
    > >>
    > >>
    > >
    > >
    >
    >

  • Next message: Adina Hagege [MSFT]: "Re: September 22 Chat: ISA Server 2004 Enabling Remote Client (VPN) Access"
    Loading