October 2007 - ogsa-d-wg

Reminder: Architecture Document in Public Comment
by Allen Luniewski 22 Oct '07

22 Oct '07

The OGSA Data Architecture architecture document is nearing the end of its 30 day public comment period. Please take a look at it and submit your comments, even if it is little more than "I read it". You can make public comments at http://forge.gridforum.org/sf/discussion/do/listTopics/projects.ggf-editor/… . You have to be logged in to be able to leave comments. Thanks. Allen Luniewski IBM Cross Brand Services IBM Silicon Valley Laboratory 555 Bailey Ave. San Jose, CA 95141 408-463-2255 408-930-1844 (mobile)

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OGSA-DAI workshop at OGF21
by Mario Antonioletti 12 Oct '07

12 Oct '07

Hi, Apologies if you receive this multiple time. This originates from Richard Sinnott the OGSA-DAI User Group chair. ................. Dear All, I am putting a workshop at OGF21 together which you may wish to attend. The basic idea is to consider the complete spectrum of data work across OGF, from the higher level vision being defined by the OGSA data architecture group; the data standards being produced such as DAIS and ByteIO; the technologies realising these standards such as OGSA-DAIv3 and then to the end user developers trying to building applications with these technologies. Think of it as microcosm of OGF as a whole. This workshop will take place at OGF21 in the Leonesa-1 room on Tuesday from 3-4.30pm. The agenda for the workshop is: 3pm INTRODUCTION - Richard Sinnott (NeSC Glasgow) 3.05pm The BIG PICTURE::OGSA Data architecture in a nutshell - Allan Luniewski (IBM) 3.25pm THE STANDARDS::OGSA Data standards (DAIS/ByteIO) - Ally Hume (EPCC) 3.45pm THE DEVELOPERS::Applying OGSA-DAIv3 in the Clinical Domain - A.Stell (NeSC Glasgow) 4.0pm WRAP UP/DISCUSSION 4.30pm CLOSE If like me you get a little lost in how OGF the different activities hang together, the idea behind this workshop is to provide a snapshot of what is going on and a reality check of the work in the data area. Rich -- Professor Richard O. Sinnott Technical Director National e-Science Centre University of Glasgow, Glasgow G12 8QQ Tel: +44-(0)141-330-8606 Fax: -8625 Mob: 0795-2376627 Email: r.sinnott(a)nesc.gla.ac.uk

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New version of Data Architecture
by Dave Berry 11 Oct '07

11 Oct '07

I've uploaded a new version of the Data Architecture, modified with responses to all the public comments received so far. This is in the Working Documents folder. Dave

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Re: [OGSA-D-WG] Fw: Definition of data consistency
by Dave Berry 11 Oct '07

11 Oct '07

I like this approach. Is it worth embellishing it as follows: Data consistency: An instance of data in one resource in a distributed system is said to be "consistent" with one or more other instances of that data elsewhere in the system if it is up-to-date with respect to those instances. In a given system a policy may define the rules for determining the extent to which data is up-to-date, and for maintaining that degree of consistency. The changes are: paragraph 1 - to talk about different resources in a distributed system (putting some context on "data instances", which is not a term we define). paragraph 2 - to introduce the notion of a degree of consistency rather than simply consistent/inconsistent. I don't feel strongly about either of these - what do others think? Dave. _____ From: ogsa-d-wg-bounces(a)ogf.org [mailto:ogsa-d-wg-bounces@ogf.org] On Behalf Of Allen Luniewski Sent: 09 October 2007 17:50 To: ogsa-d-wg(a)ggf.org Subject: [OGSA-D-WG] Fw: Definition of data consistency Please see Jem's note below - he can not post to this DL. I think that his suggestion is a good one. Allen Luniewski IBM Cross Brand Services IBM Silicon Valley Laboratory 555 Bailey Ave. San Jose, CA 95141 408-463-2255 408-930-1844 (mobile) ----- Forwarded by Allen Luniewski/Almaden/IBM on 10/09/2007 09:49 AM ----- "Treadwell, Jem" <jem.treadwell(a)hp.com> 10/09/2007 09:40 AM To Dave Berry <daveb(a)nesc.ac.uk>, Allen Luniewski <luniew(a)almaden.ibm.com> cc Subject FW: [OGSA-D-WG] ***SPAM*** Definition of data consistency Allen/Dave, I can't mail the data mailing list, so please feel free to pass this on if you think it's worthwhile. I agree with Allen about sounding specific, and this is a hard thing to turn into a direct definition without using some term such as "indication." You might think about using an indirect form: Data consistency: An instance of data is said to be "consistent" with one or more other instances of that data if it is up-to-date with respect to those instances. That may be enough, but you could also add something like: In a given system a policy may define the rules for determining whether data is up-to-date, and for maintaining consistency. - Jem Jem Treadwell Software Engineer HP ESS Software 856.638.6021 office | 856.638.6190 fax | jem.treadwell(a)hp.com <mailto:jem.treadwell@hp.com> 6000 Irwin Road | Mount Laurel | NJ 08054 http://www.hp.com/go/vse <http://www.hp.com/go/vse> <http://www.hp.com/go/software> _____ From: Allen Luniewski [mailto:luniew@us.ibm.com] Sent: Monday, October 08, 2007 5:20 PM To: Dave Berry Cc: Treadwell, Jem; ogsa-d-wg(a)ogf.org Subject: Re: [OGSA-D-WG] ***SPAM*** Definition of data consistency Dave, I think that I am okay with that suggested change. I am a little bit worried about using the word "measure" as it can be taken to imply things that we really do not want to address (e.g., a means to measure and a quantifiable scale for measurement). I thought about suggesting changing "A measure" to "An indication" but that seems just a bit too vague to me. I don't have a better suggestion right now. Allen Luniewski IBM Cross Brand Services IBM Silicon Valley Laboratory 555 Bailey Ave. San Jose, CA 95141 408-463-2255 408-930-1844 (mobile) "Dave Berry" <daveb(a)nesc.ac.uk> "Dave Berry" <daveb(a)nesc.ac.uk> Sent by: ogsa-d-wg-bounces(a)ogf.org 10/08/2007 02:11 PM To <ogsa-d-wg(a)ogf.org> cc "Treadwell, Jem" <jem.treadwell(a)hp.com> Subject [OGSA-D-WG] ***SPAM*** Definition of data consistency Jem queried our definition of data consistency, which is currently: A policy that specifies or describes how up-to-date an instance of data is in one service of a distributed system, with respect to one or more instances of that data elsewhere in the system. Jem said (in e-mail): my thought was that data consistency would be a state of the data - it's consistent w.r.t. some other set of data or it isn't; the policy would be the rules that determine whether it is, and what the requirements are. I've had a look through our document and I agree. We refer to data consistency policies but also to data consistency requirements, mechanisms and strategies. So, how about this as a revised definntion: "A measure of how up-to-date an instance of data is in one service of a distributed system, with respect to one or more instances of that data elsewhere in the system." Best wishes, Dave Berry Deputy Director, Research & E-infrastructure Development National e-Science Centre 15 South College Street, Edinburgh, EH8 9AA +44 131 651 4039 www.nesc.ac.uk <http://www.nesc.ac.uk/> -- ogsa-d-wg mailing list ogsa-d-wg(a)ogf.org http://www.ogf.org/mailman/listinfo/ogsa-d-wg <http://www.ogf.org/mailman/listinfo/ogsa-d-wg>

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Fw: Definition of data consistency
by Allen Luniewski 09 Oct '07

09 Oct '07

Please see Jem's note below - he can not post to this DL. I think that his suggestion is a good one. Allen Luniewski IBM Cross Brand Services IBM Silicon Valley Laboratory 555 Bailey Ave. San Jose, CA 95141 408-463-2255 408-930-1844 (mobile) ----- Forwarded by Allen Luniewski/Almaden/IBM on 10/09/2007 09:49 AM ----- "Treadwell, Jem" <jem.treadwell@hp .com> To Dave Berry <daveb(a)nesc.ac.uk>, 10/09/2007 09:40 Allen Luniewski AM <luniew(a)almaden.ibm.com> cc Subject FW: [OGSA-D-WG] ***SPAM*** Definition of data consistency Allen/Dave, I can’t mail the data mailing list, so please feel free to pass this on if you think it’s worthwhile. I agree with Allen about sounding specific, and this is a hard thing to turn into a direct definition without using some term such as “indication.” You might think about using an indirect form: Data consistency: An instance of data is said to be “consistent” with one or more other instances of that data if it is up-to-date with respect to those instances. That may be enough, but you could also add something like: In a given system a policy may define the rules for determining whether data is up-to-date, and for maintaining consistency. - Jem Jem Treadwell Software Engineer HP ESS Software 856.638.6021 office | 856.638.6190 fax | jem.treadwell(a)hp.com 6000 Irwin Road | Mount Laurel | NJ 08054 http://www.hp.com/go/vse hp From: Allen Luniewski [mailto:luniew@us.ibm.com] Sent: Monday, October 08, 2007 5:20 PM To: Dave Berry Cc: Treadwell, Jem; ogsa-d-wg(a)ogf.org Subject: Re: [OGSA-D-WG] ***SPAM*** Definition of data consistency Dave, I think that I am okay with that suggested change. I am a little bit worried about using the word "measure" as it can be taken to imply things that we really do not want to address (e.g., a means to measure and a quantifiable scale for measurement). I thought about suggesting changing "A measure" to "An indication" but that seems just a bit too vague to me. I don't have a better suggestion right now. Allen Luniewski IBM Cross Brand Services IBM Silicon Valley Laboratory 555 Bailey Ave. San Jose, CA 95141 408-463-2255 408-930-1844 (mobile) Inactive hide details for "Dave Berry" <daveb(a)nesc.ac.uk>"Dave Berry" <daveb(a)nesc.ac.uk> "Dave Berry" <daveb(a)nesc.a c.uk> Sent by: ogsa-d-wg-bou To nces(a)ogf.org <ogsa-d-wg(a)ogf.org> 10/08/2007 cc 02:11 PM "Treadwell, Jem" <jem.treadwell(a)hp.com> Subject [OGSA-D-WG] ***SPAM*** Definition of data consistency Jem queried our definition of data consistency, which is currently: |--------------------------------------------------------------------------| | A policy that specifies or describes how up-to-date an instance of data | | is in one service of a distributed system, with respect to one or more | | instances of that data elsewhere in the system. | |--------------------------------------------------------------------------| Jem said (in e-mail): my thought was that data consistency would be a state of the data - it's consistent w.r.t. some other set of data or it isn't; the policy would be the rules that determine whether it is, and what the requirements are. I've had a look through our document and I agree. We refer to data consistency policies but also to data consistency requirements, mechanisms and strategies. So, how about this as a revised definntion: "A measure of how up-to-date an instance of data is in one service of a distributed system, with respect to one or more instances of that data elsewhere in the system." Best wishes, Dave Berry Deputy Director, Research & E-infrastructure Development National e-Science Centre 15 South College Street, Edinburgh, EH8 9AA +44 131 651 4039 www.nesc.ac.uk -- ogsa-d-wg mailing list ogsa-d-wg(a)ogf.org http://www.ogf.org/mailman/listinfo/ogsa-d-wg

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***SPAM*** Definition of data consistency
by Dave Berry 08 Oct '07

08 Oct '07

Jem queried our definition of data consistency, which is currently: A policy that specifies or describes how up-to-date an instance of data is in one service of a distributed system, with respect to one or more instances of that data elsewhere in the system. Jem said (in e-mail): my thought was that data consistency would be a state of the data - it's consistent w.r.t. some other set of data or it isn't; the policy would be the rules that determine whether it is, and what the requirements are. I've had a look through our document and I agree. We refer to data consistency policies but also to data consistency requirements, mechanisms and strategies. So, how about this as a revised definntion: "A measure of how up-to-date an instance of data is in one service of a distributed system, with respect to one or more instances of that data elsewhere in the system." Best wishes, Dave Berry Deputy Director, Research & E-infrastructure Development National e-Science Centre 15 South College Street, Edinburgh, EH8 9AA +44 131 651 4039 www.nesc.ac.uk <http://www.nesc.ac.uk/>

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Definition of data consistency [RESEND]
by Dave Berry 08 Oct '07

08 Oct '07

[As my first attempt got flagged as spam, I'm resending this] Jem queried our definition of data consistency, which is currently: "A policy that specifies or describes how up-to-date an instance of data is in one service of a distributed system, with respect to one or more instances of that data elsewhere in the system." Jem said (in e-mail): "My thought was that data consistency would be a state of the data - it's consistent w.r.t. some other set of data or it isn't; the policy would be the rules that determine whether it is, and what the requirements are." I've had a look through our document and I agree. We refer to data consistency policies but also to data consistency requirements, mechanisms and strategies. So, how about this as a revised definntion: "A measure of how up-to-date an instance of data is in one service of a distributed system, with respect to one or more instances of that data elsewhere in the system." Best wishes, Dave Berry Deputy Director, Research & E-infrastructure Development National e-Science Centre 15 South College Street, Edinburgh, EH8 9AA +44 131 651 4039 www.nesc.ac.uk

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OGSA Data Telcon Minutes
by Mario Antonioletti 05 Oct '07

05 Oct '07

OGSA Data Working Group Telcon - 04/10/07 ========================================= Agenda: - OGF21 - Public Comments Attendees: Dave Berry, NeSC Mario Antonioletti, EPCC Allen Luniewski, IBM o OGF21 Allen found out he could go to OGF21 during the call so the OGSA Data Architecture session at OGF21 can go ahead. o Public Comments http://forge.gridforum.org/sf/discussion/do/listTopics/projects.ggf-editor/… Comment by Peter Kunszt about affiliation is straightforward to fix. Comment by Jem Treadwell about data consistency, we need to check how we are using the term or whether we should associate the term policy with that. Comment by Dave Berry about typos in the glossary should be trivial to fix. Comments by Hiro Kishimoto, first one is easy to deal with, some text got cut off in the figure and numbering of services (using letters), and rewording of ByteIO to OGSA ByteIO and DMI to OGSA DMI. Question about moving data transfer paragraph to an earlier section may require some rewording and some shifting. Should use client as opposed to consumer - generally agreed. Comment in section 2.5 will require rephrasing. We do not use italics consistently (not in the glossary) Consistency about capitalisation of bullet points. We need to look at the comment: '"Secure channel" is Security Profile instead of Basic Security Profile.' (HK7) - maybe remove the word Basic from "OGSA Basic Security Profile". HK8 should be a straightforward change to move normative document to a set of profiles. HK9 - add a table caption. Need to change the associated text too to reference the table. HK10 - this will have to be added into the text. HK11 & HK12 - may not want to use bold but the point is taken. A number of in-lined changes are ok'ed. change "services -> interface and protocols" is ok but it should be interfaces. HK13 - requires discussion - we remove the current suggested recommendation OASIS CIM TC that is already there. HK14 - needs to be updated, check references to WS Policy. HK15 - yep HK16 - yes but may require some word smithing. HK17 - requires discussion, don't want to talk about workflow. HK18 - needs to be discussed, should probably be done via EMS. Need to discuss Reservation with an OGSA Person. Add a section on 3.13 on Information services: Please add Information Service (e.g. repository, catalog or directory) here. Data services can use information service. On the other hand, Information Service use data service for its storage. Allen will chase this one up. +-- Try to get more people to comment on the document. DONM: 2 Nov 07, 4pm BST. +-----------------------------------------------------------------------+ |Mario Antonioletti:EPCC,JCMB,The King's Buildings,Edinburgh EH9 3JZ. | |Tel:0131 650 5141|mario@epcc.ed.ac.uk|http://www.epcc.ed.ac.uk/~mario/ | +-----------------------------------------------------------------------+

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Re: [OGSA-D-WG] [ogsa-wg] OGSA Glossary v1.6: Final call for comments
by Mario Antonioletti 04 Oct '07

04 Oct '07

Message from Jem Treadwell - his posting to this list bounced so forwarding on: ---------- Forwarded message ---------- Date: Wed, 3 Oct 2007 23:12:05 -0400 From: "Treadwell, Jem" <jem.treadwell(a)hp.com> To: Mario Antonioletti <mario(a)epcc.ed.ac.uk>, guru prasad <guru_bn(a)yahoo.com> Cc: ogsa-d-wg(a)ggf.org, ogsa-wg <ogsa-wg(a)ogf.org>, felixehm(a)mail.cern.ch Subject: RE: [ogsa-wg] OGSA Glossary v1.6: Final call for comments Guru, thanks for your comment. Dave Berry has been keeping the definitions in the OGSA Glossary in step with the Data Architecture definitions, and in fact they are in line with the public-comment version of that document. I have a placeholder in the Glossary for a reference to the final version of the Data document, and I'll work with Dave to make sure the definitions remain in sync. It's probably helpful that we'll be a couple of weeks behind the Data doc. Thanks! - Jem Jem Treadwell Software Engineer HP ESS Software 856.638.6021 office | 856.638.6190 fax | jem.treadwell(a)hp.com 6000 Irwin Road | Mount Laurel | NJ 08054 www.hp.com/go/software hp > -----Original Message----- > From: ogsa-wg-bounces(a)ogf.org [mailto:ogsa-wg-bounces@ogf.org] On Behalf > Of Mario Antonioletti > Sent: Wednesday, October 03, 2007 10:21 AM > To: guru prasad > Cc: ogsa-d-wg(a)ggf.org; ogsa-wg; felixehm(a)mail.cern.ch > Subject: Re: [ogsa-wg] OGSA Glossary v1.6: Final call for comments > > > Guru, > I am a little disappointed that you are not cc'ing the OGSA Data > Working Group where this discussion would be of particular interest. > It would be invaluable though, if you think there are deficiencies, in > these definitions or in the OGSA Data Architecture in general for you > to comment on the OGSA Data Architecture document at: > > http://www.ogf.org/gf/docs/?public_comment > > which is where these originated from. Thanks in advance, > > Mario > > On Wed, 3 Oct 2007, guru prasad wrote: > >> Sure I was more under the impression that these definitions are being > finalized. >> >> BTW I am guruprasad. >> >> Andreas Savva <andreas.savva(a)jp.fujitsu.com> wrote: Hi, >> >> Since the Data Architecture document itself has gone to public comment I >> see no reason to stop the Glossary from moving to that state. We can fix >> the definitions as part of the public comment discussion. >> >> Andreas >> >> guru prasad wrote: >>> Hello Jem, >>> >>> A parallel discussion on Data Service, Data Source, Data Resource is >>> happening and we have not reached a common grounds for these > definitions >>> yet. >>> >>> NOTE: I am cc'ing donal and felix who were a part of those dicussions. >>> >>> So in my opinion this glossary cannot be finalized until we come up > with >>> agreeable definition for these terms. >>> >>> Thanks, >>> Guru >>> >>> "Treadwell, Jem" wrote: >>> >>> Hi, >>> >>> The OGSA Glossary v1.6 is now available for any final comments >>> before submission to the OGF Editor. Youâ€™ll find a copy of the > document >>> (draft 8) at http://tinyurl.com/2t4on2. If you have comments please let >>> me have them by the end of Sunday, October 7th. >>> >>> Thanks! >>> >>> - Jem >>> >>> >>> >>> Jem Treadwell >>> Software Engineer >>> >>> HP ESS Software >>> 856.638.6021 office | 856.638.6190 fax | jem.treadwell(a)hp.com >>> 6000 Irwin Road | Mount Laurel | NJ 08054 >>> http://www.hp.com/go/vse >>> >>> hp >>> >>> >>> -- >>> ogsa-wg mailing list >>> ogsa-wg(a)ogf.org >>> http://www.ogf.org/mailman/listinfo/ogsa-wg >>> >>> >>> */"Treadwell, Jem" /* wrote: >>> >>> Hi, >>> The OGSA Glossary v1.6 is now available for any final comments >>> before submission to the OGF Editor. Youâ€™ll find a copy of the >>> document (draft 8) at http://tinyurl.com/2t4on2. If you have >>> comments please let me have them by the end of *Sunday, October > 7^th *. >>> Thanks! >>> - Jem >>> >>> **Jem Treadwell** >>> Software Engineer >>> *HP ESS Software* >>> 856.638.6021 office | 856.638.6190 fax | jem.treadwell(a)hp.com >>> >>> 6000 Irwin Road | Mount Laurel | NJ 08054 >>> http://www.hp.com/go/vse >>> hp >>> >>> -- >>> ogsa-wg mailing list >>> ogsa-wg(a)ogf.org >>> http://www.ogf.org/mailman/listinfo/ogsa-wg >>> >>> >>> ----------------------------------------------------------------------- > - >>> Fussy? Opinionated? Impossible to please? Perfect. Join Yahoo!'s user >>> panel >>>>> and lay it on us. >>> >>> >>> ----------------------------------------------------------------------- > - >>> >>> -- >>> ogsa-wg mailing list >>> ogsa-wg(a)ogf.org >>> http://www.ogf.org/mailman/listinfo/ogsa-wg >> >> >> >> >> --------------------------------- >> Tonight's top picks. What will you watch tonight? Preview the hottest > shows on Yahoo! TV. > > +-----------------------------------------------------------------------+ > |Mario Antonioletti:EPCC,JCMB,The King's Buildings,Edinburgh EH9 3JZ. | > |Tel:0131 650 5141|mario@epcc.ed.ac.uk|http://www.epcc.ed.ac.uk/~mario/ | > +-----------------------------------------------------------------------+

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Re: [OGSA-D-WG] [ogsa-wg] OGSA Glossary v1.6: Final call for comments
by Mario Antonioletti 04 Oct '07

04 Oct '07

Guru, I am a little disappointed that you are not cc'ing the OGSA Data Working Group where this discussion would be of particular interest. It would be invaluable though, if you think there are deficiencies, in these definitions or in the OGSA Data Architecture in general for you to comment on the OGSA Data Architecture document at: http://www.ogf.org/gf/docs/?public_comment which is where these originated from. Thanks in advance, Mario On Wed, 3 Oct 2007, guru prasad wrote: > Sure I was more under the impression that these definitions are being finalized. > > BTW I am guruprasad. > > Andreas Savva <andreas.savva(a)jp.fujitsu.com> wrote: Hi, > > Since the Data Architecture document itself has gone to public comment I > see no reason to stop the Glossary from moving to that state. We can fix > the definitions as part of the public comment discussion. > > Andreas > > guru prasad wrote: >> Hello Jem, >> >> A parallel discussion on Data Service, Data Source, Data Resource is >> happening and we have not reached a common grounds for these definitions >> yet. >> >> NOTE: I am cc'ing donal and felix who were a part of those dicussions. >> >> So in my opinion this glossary cannot be finalized until we come up with >> agreeable definition for these terms. >> >> Thanks, >> Guru >> >> "Treadwell, Jem" wrote: >> >> Hi, >> >> The OGSA Glossary v1.6 is now available for any final comments >> before submission to the OGF Editor. You’ll find a copy of the document >> (draft 8) at http://tinyurl.com/2t4on2. If you have comments please let >> me have them by the end of Sunday, October 7th. >> >> Thanks! >> >> - Jem >> >> >> >> Jem Treadwell >> Software Engineer >> >> HP ESS Software >> 856.638.6021 office | 856.638.6190 fax | jem.treadwell(a)hp.com >> 6000 Irwin Road | Mount Laurel | NJ 08054 >> http://www.hp.com/go/vse >> >> hp >> >> >> -- >> ogsa-wg mailing list >> ogsa-wg(a)ogf.org >> http://www.ogf.org/mailman/listinfo/ogsa-wg >> >> >> */"Treadwell, Jem" /* wrote: >> >> Hi, >> The OGSA Glossary v1.6 is now available for any final comments >> before submission to the OGF Editor. You’ll find a copy of the >> document (draft 8) at http://tinyurl.com/2t4on2. If you have >> comments please let me have them by the end of *Sunday, October 7^th *. >> Thanks! >> - Jem >> >> **Jem Treadwell** >> Software Engineer >> *HP ESS Software* >> 856.638.6021 office | 856.638.6190 fax | jem.treadwell(a)hp.com >> >> 6000 Irwin Road | Mount Laurel | NJ 08054 >> http://www.hp.com/go/vse >> hp >> >> -- >> ogsa-wg mailing list >> ogsa-wg(a)ogf.org >> http://www.ogf.org/mailman/listinfo/ogsa-wg >> >> >> ------------------------------------------------------------------------ >> Fussy? Opinionated? Impossible to please? Perfect. Join Yahoo!'s user >> panel >>>> and lay it on us. >> >> >> ------------------------------------------------------------------------ >> >> -- >> ogsa-wg mailing list >> ogsa-wg(a)ogf.org >> http://www.ogf.org/mailman/listinfo/ogsa-wg > > > > > --------------------------------- > Tonight's top picks. What will you watch tonight? Preview the hottest shows on Yahoo! TV. +-----------------------------------------------------------------------+ |Mario Antonioletti:EPCC,JCMB,The King's Buildings,Edinburgh EH9 3JZ. | |Tel:0131 650 5141|mario@epcc.ed.ac.uk|http://www.epcc.ed.ac.uk/~mario/ | +-----------------------------------------------------------------------+

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