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<DIV><SPAN class=905193211-17092002><FONT face=Arial color=#0000ff size=2>Here's
the feedback. I'll be working on this in the background, but input is
encouraged. Clearly there is a disconnect and we have to get our story
straight so we can answer these questions. The nuts and bolts of the issues
have to support our claims, or we're wasting our and Tony's
time.</FONT></SPAN></DIV>
<DIV><SPAN class=905193211-17092002><FONT face=Arial color=#0000ff
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=905193211-17092002><FONT face=Arial color=#0000ff
size=2>--Ivan</FONT></SPAN></DIV>
<DIV> </DIV>
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<P><FONT size=2></FONT> </P>
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style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #0000ff 2px solid; MARGIN-RIGHT: 0px">
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<DIV class=OutlookMessageHeader lang=en-us dir=ltr align=left><FONT
face=Tahoma size=2>-----Original Message-----<BR><B>From:</B> Michael Daw
[mailto:mike.daw@man.ac.uk] <BR><B>Sent:</B> Tuesday, September 17, 2002 3:24
AM<BR><B>To:</B> Sue Rogers; Stewart Macneill; Stephen Booth; Richard Ansorge;
Paul Jeffreys; Mike Giles; Mark Hayes; Mark Cavanagh; Malcolm Atkinson; Liz
Carver; Kate Caldwell; John Gordon; John Brooke; Jeremy Sharp; Ivan R. Judson;
Henry Hughes; David Salmon; David Hutchison; David De Roure; David Boyd; Chris
Osland; Brian Gilmore; Alan J. Flavell; Peter Clarke<BR><B>Cc:</B>
galvez@hep.caltech.edu<BR><B>Subject:</B> The return of the
report<BR><BR></FONT></DIV>
<DIV><FONT face=Arial color=#0000ff size=2><SPAN class=734344315-16092002>Dear
team,</SPAN></FONT></DIV>
<DIV><FONT face=Arial color=#0000ff size=2><SPAN
class=734344315-16092002></SPAN></FONT> </DIV>
<DIV><FONT face=Arial color=#0000ff size=2><SPAN class=734344315-16092002>It's
not over yet!</SPAN></FONT></DIV>
<DIV><FONT face=Arial color=#0000ff size=2><SPAN
class=734344315-16092002></SPAN></FONT> </DIV>
<DIV><FONT face=Arial color=#0000ff size=2><SPAN
class=734344315-16092002>Below is Tony's second e-mail on the subject of the
report forwarding a response from the VRVS team at Caltech. (Just so you know,
his first e-mail said </SPAN></FONT><FONT size=+0><SPAN
class=734344315-16092002><FONT face=Arial><FONT color=#0000ff><FONT
size=2><SPAN class=734344315-16092002>"</SPAN>I liked your report very much
and hope we can take something forward from your recommendations<SPAN
class=734344315-16092002>".) </SPAN></FONT></FONT></FONT></SPAN></FONT></DIV>
<DIV><FONT size=+0><SPAN class=734344315-16092002><FONT face=Arial><FONT
color=#0000ff><FONT size=2><SPAN
class=734344315-16092002></SPAN></FONT></FONT></FONT></SPAN></FONT> </DIV>
<DIV><FONT size=+0><SPAN class=734344315-16092002><FONT face=Arial><FONT
color=#0000ff><FONT size=2><SPAN class=734344315-16092002>So - Tony wants the
report revised in light of these comments. While we're at it, we should also
incorporate some concerns expressed by a couple of other people. Then the
report can be disseminated widely, as Tony
says.</SPAN></FONT></FONT></FONT></SPAN></FONT></DIV>
<DIV><FONT size=+0><SPAN class=734344315-16092002><FONT face=Arial><FONT
color=#0000ff><FONT size=2><SPAN
class=734344315-16092002></SPAN></FONT></FONT></FONT></SPAN></FONT> </DIV>
<DIV><FONT size=+0><SPAN class=734344315-16092002><FONT face=Arial><FONT
color=#0000ff><FONT size=2><SPAN class=734344315-16092002>What I suggest is
that those of you who are interested in helping with the re-draft let me know.
I'll then co-ordinate some kind of meeting to discuss how to take this
forward. I'd like to keep the current contributors on this
distribution list so that they can comment on revisions and remain on the
contributor list. I've cc-ed Phillippe too so that he - or someone at Caltech
- can be a full member of the re-draft
team.</SPAN></FONT></FONT></FONT></SPAN></FONT></DIV>
<DIV><FONT size=+0><SPAN class=734344315-16092002><FONT face=Arial><FONT
color=#0000ff><FONT size=2><SPAN
class=734344315-16092002></SPAN></FONT></FONT></FONT></SPAN></FONT> </DIV>
<DIV><FONT size=+0><SPAN class=734344315-16092002><FONT face=Arial><FONT
color=#0000ff><FONT size=2><SPAN class=734344315-16092002>Please tell me if
you can think of better ways forward, or have questions or comments on
anything related (or unrelated, for that
matter).</SPAN></FONT></FONT></FONT></SPAN></FONT></DIV>
<DIV><FONT size=+0><SPAN class=734344315-16092002><FONT face=Arial><FONT
color=#0000ff><FONT size=2><SPAN
class=734344315-16092002></SPAN></FONT></FONT></FONT></SPAN></FONT> </DIV>
<DIV><FONT size=+0><SPAN class=734344315-16092002><FONT face=Arial><FONT
color=#0000ff><FONT size=2><SPAN
class=734344315-16092002>--Mike</SPAN></FONT></FONT></FONT></SPAN></FONT></DIV>
<DIV><FONT face=Tahoma><FONT size=2><SPAN class=734344315-16092002><FONT
face=Arial></FONT></SPAN></FONT></FONT> </DIV>
<DIV class=OutlookMessageHeader dir=ltr align=left><FONT face=Tahoma><FONT
size=2><SPAN class=734344315-16092002></SPAN></FONT></FONT> </DIV>
<DIV class=OutlookMessageHeader dir=ltr align=left><FONT face=Tahoma><FONT
size=2><SPAN class=734344315-16092002> </SPAN>-----Original
Message-----<BR><B>From:</B> Tony Hey
[mailto:Tony.Hey@epsrc.ac.uk]<BR><B>Sent:</B> 16 September 2002
13:44<BR><B>To:</B> 'mike.daw@man.ac.uk'<BR><B>Cc:</B> Tony Hey; Ray Browne
(Ray.Browne@dti.gsi.gov.uk); James Fleming; Anne Trefethen<BR><B>Subject:</B>
FW: FW: Background Document for JCSR<BR><BR></DIV></FONT></FONT>
<P><FONT size=2>Mike</FONT> </P>
<P><FONT size=2>Thanks for your note - I am forwarding some comments from the
VRVS team at Caltech which seem to me to have some merit! And this answers my
strategy as to publication - I would like your team to consider these comments
and produce any revisions (if necessary - but I will require an answer from
you to their points!) to your paper. Then we would like it circulated widely.
There is also every possibility that JCSR will be willing to fund some of your
recommendations ...</FONT></P>
<P><FONT size=2>Best wishes</FONT> </P>
<P><FONT size=2>Tony</FONT> </P>
<P><FONT size=2>Professor Tony Hey</FONT> <BR><FONT size=2>Director e-Science
Core Programme</FONT> <BR><FONT size=2>Engineering and Physical Sciences
Research Council (EPSRC)</FONT> <BR><FONT size=2>Polaris House</FONT>
<BR><FONT size=2>North Star Avenue</FONT> <BR><FONT size=2>SWINDON</FONT>
<BR><FONT size=2>Wiltshire SN2 1ET</FONT> <BR><FONT
size=2>ENGLAND</FONT> <BR><FONT size=2>Tel: +44(0)1793 444022 Fax:
+44(0)1793 444505</FONT> <BR><FONT size=2><A href="http://www.epsrc.ac.uk"
target=_blank>http://www.epsrc.ac.uk</A> </FONT><BR><FONT size=2><A
href="http://www.research-councils.ac.uk/"
target=_blank>http://www.research-councils.ac.uk/</A> </FONT><BR><FONT
size=2><A href="http://www.escience-grid.org.uk"
target=_blank>http://www.escience-grid.org.uk</A> </FONT><BR><FONT
size=2><A href="http://umbriel.dcs.gla.ac.uk/NeSC/general/"
target=_blank>http://umbriel.dcs.gla.ac.uk/NeSC/general/</A>
</FONT></P><BR>
<P><FONT size=2>-----Original Message-----</FONT> <BR><FONT size=2>From:
Philippe Galvez [<A
href="mailto:galvez@hep.caltech.edu">mailto:galvez@hep.caltech.edu</A>]
</FONT><BR><FONT size=2>Sent: 15 September 2002 21:48</FONT> <BR><FONT
size=2>To: Harvey Newman</FONT> <BR><FONT size=2>Cc: Tony Hey; Philippe
Galvez; Alan J. Flavell</FONT> <BR><FONT size=2>Subject: Re: FW: Background
Document for JCSR</FONT> </P>
<P><FONT size=2>Dear Tony,</FONT> </P>
<P><FONT size=2>Harvey and I went over the document and made additional
comments. I hope</FONT> <BR><FONT size=2>you will find it useful and
constructive. feel to contact us for more</FONT> <BR><FONT size=2>detail. I
will be glad to discuss any topics that you will find</FONT> <BR><FONT
size=2>appropriated.</FONT> </P>
<P><FONT size=2> Regards,</FONT>
<BR><FONT size=2> Philipps</FONT>
</P>
<P><FONT size=2>cc: Harvey Newman, Alan Flavell</FONT> </P><BR>
<P><FONT size=2>------------------------------------</FONT> </P>
<P><FONT size=2> o My first comment concerns the list of
contributors. I see on the</FONT> <BR><FONT size=2>list Ivan Judson (from
ANL/AG, AG's architect) and Jim Miller from</FONT> <BR><FONT size=2>InSORS. In
this regard, I am a bit surprised that the people preparing</FONT> <BR><FONT
size=2>the report didn't contact us directly if they wanted a
balanced</FONT> <BR><FONT size=2>evaluation, while avoiding technical errors
and misconceptions.</FONT> <BR><FONT size=2>Hopefully, Alan Flavell
contributed to the VRVS parts as he is one</FONT> <BR><FONT size=2>person who
understands for the most part what VRVS is.</FONT> </P>
<P><FONT size=2> o The executive Summary is good.</FONT>
</P>
<P><FONT size=2> Comments by Section follow:</FONT> </P>
<P><FONT size=2> o 2.1: Technically speaking, I don't
understand the planned usage of</FONT> <BR><FONT size=2>openMCU to enable
interoperability between H.323 and AG. First of all,</FONT> <BR><FONT
size=2>VRVS has done it -- completely. Second, it is definitely not the
right</FONT> <BR><FONT size=2>technical solution. I already informed the AG
guys about it but looks</FONT> <BR><FONT size=2>like they want to insist on
using it without first understanding the</FONT> <BR><FONT size=2>openMCU
architecture and its limitations..</FONT> </P>
<P><FONT size=2> o 2.4: The interoperability between AG and
VRVS is already done. The</FONT> <BR><FONT size=2>further deployment of
AG/VRVS in UK and other countries could be done</FONT> <BR><FONT
size=2>easily, as well as full support for more AG virtual venues.</FONT>
<BR><FONT size=2>Something that people didn't get is that the current
AG/VRVS Gateway</FONT> <BR><FONT size=2>has never been in the "Funded Tasks
development list". We simply did it:</FONT> <BR><FONT size=2>because there was
a need, and because our architecture was flexible</FONT> <BR><FONT
size=2>enough so that we were able to do it with minimal resources. This
is</FONT> <BR><FONT size=2>just one of several examples where people do not
quite realize the</FONT> <BR><FONT size=2>potential of our realtime software
infrastructure, and conversely assume</FONT> <BR><FONT size=2>limitations in
the VRVS system that don't exist.</FONT> <BR><FONT size=2>In this case if
people think that VRVS/AG gateway improvements are</FONT> <BR><FONT
size=2>needed right now, then we could do it in return for a moderate amount
of</FONT> <BR><FONT size=2>funding -- to improve the gateway GUI, to deploy
it, and to provide a</FONT> <BR><FONT size=2>bit of support. The funding is
only needed because we would have to push</FONT> <BR><FONT size=2>other tasks
on our long in-progress development list; or (better) we</FONT> <BR><FONT
size=2>would take on another engineer to keep all of our milestones
(including</FONT> <BR><FONT size=2>the VRVS/AG ones) on schedule.</FONT> </P>
<P><FONT size=2> o 2.4: I don't understand "It is not possible for
an Access Grid to</FONT> <BR><FONT size=2>participate in a VRVS session". This
is not true. And the solutions</FONT> <BR><FONT size=2>proposed do not take in
account the current technique used in the</FONT> <BR><FONT
size=2>gateway.</FONT> <BR><FONT size=2>It would be better to ask us is there
is a presumed problem: (a) to</FONT> <BR><FONT size=2>find out if it is
already done, (b) to allow us to propose solutions,</FONT> <BR><FONT
size=2>which in the great majority of cases will be quite straightforward
for</FONT> <BR><FONT size=2>us.</FONT> </P>
<P><FONT size=2> o 3.4, H.323/H.320: These are Not
broadcast quality as mentioned</FONT> <BR><FONT size=2>here. CIF (352 X
288) is half the resolution of broadcasts. In</FONT> <BR><FONT
size=2>continuous presence (4 videos on a screen) one has QCIF for each
video</FONT> <BR><FONT size=2>which is 4 times less resolution per video
than broadcast.</FONT> </P>
<P><FONT size=2> o 3.7 AG: A solution purely multicast based
is surely not "the only</FONT> <BR><FONT size=2>fully scalable solution for
large-scale collaboration" as it is</FONT> <BR><FONT size=2>mentioned in the
report. It has been demonstrated since the early</FONT> <BR><FONT
size=2>1990's that the opposite is true. In contrast, it has been
recognized</FONT> <BR><FONT size=2>(e.g. at high performance network meetings
organized by DOE this Summer)</FONT> <BR><FONT size=2>that using unicast
tunnels where needed to interconnect mulitcast</FONT> <BR><FONT
size=2>domains is demonstrably scalable. This is why VRVS has
spread to 60+</FONT> <BR><FONT size=2>countries, and precisely why VRVS
is architected the way it is.</FONT> <BR><FONT size=2> The claim that
pure multicast is scalable in this section is in</FONT> <BR><FONT
size=2>contradiction with the following sentence, that mentions that it
will</FONT> <BR><FONT size=2>take few years for having all UK academic
LANs with multicast</FONT> <BR><FONT size=2>capability. We must point
out that multicast at network level, with</FONT> <BR><FONT size=2>large TTL is
now considered dead by leading experts such as Linda</FONT> <BR><FONT
size=2>Winkler and Matt Matthis. VRVS's unicast tunnels
inter-connecting</FONT> <BR><FONT size=2>multicast domains has been
recognized as the "obvious" globally</FONT> <BR><FONT size=2>scalable
solution; in contrast to what is said in this report.</FONT> </P>
<P><FONT size=2> o 3.7 H323: Here it is not mentioned that
H.323 devices are very</FONT> <BR><FONT size=2>sensitive to packet loss. The
adaptive/predictive protocols used by</FONT> <BR><FONT size=2>H.323,
while bringing higher interactivity and quality per unit</FONT> <BR><FONT
size=2>bandwidth, also are more sensitive to persistent "artifacts" on
the</FONT> <BR><FONT size=2>screen. Especially if packet loss is above a few
tenths of one percent.</FONT> </P>
<P><FONT size=2> o 3.9 AG: An ACL list do not provide
a secure way to operate.</FONT> <BR><FONT size=2>Multicast is definitely not
the best technique for providing security</FONT> <BR><FONT size=2>since almost
anyone on the network can sniff the packets. In this</FONT> <BR><FONT
size=2>particular case, the only solution is encryption from the
applications</FONT> <BR><FONT size=2>and today this could be done via the
Mbone tools (Vic/Rat). This is not</FONT> <BR><FONT size=2>particular to
the AG, but only related to the Mbone tools. In addition,</FONT> <BR><FONT
size=2>the encryption provided in the Mbone tools is very basic,
and anyone</FONT> <BR><FONT size=2>enough competence will be able to decrypt
it.</FONT> </P>
<P><FONT size=2> o 3.13: I don't understand what is meant by
"The AG configuration</FONT> <BR><FONT size=2>applied at the e-Sciences
Centers makes them unsuitable for VRVS</FONT> <BR><FONT size=2>conferences".
Are the AG nodes there different from all the other AG</FONT> <BR><FONT
size=2>nodes elsewhere; if so, in which ways ?</FONT> </P>
<P><FONT size=2> o 5.2: I am surprised by the cost for the
AG. Platinum 30,000 LS</FONT> <BR><FONT size=2>(UK), One could equip a whole
site with desktop cameras !.</FONT> </P>
<P><FONT size=2> o 8.1: Again, we see an incorrect
comparison of VRVS (a realtime</FONT> <BR><FONT size=2>software
infrastructure integrated with many clients) with the</FONT> <BR><FONT
size=2>application tools themselves: Netmeeting, QT, CUSeeMe,...etc..
Once</FONT> <BR><FONT size=2>again this is a failure to understand that VRVS
is not a client</FONT> <BR><FONT size=2>application, but rather provide the
infrastructure upon which many</FONT> <BR><FONT size=2>client
applications can run, and interoperate. It is like comparing</FONT>
<BR><FONT size=2>Cisco routers and the Cisco IOS software, with FTP or
Telnet.</FONT> </P>
<P><FONT
size=2>-----------------------------------------------------------</FONT>
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