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Brian Gilmore Computing Services, University of Edinburgh. Edinburgh’s Experiences. Edinburgh - The History. April 98 - University Management Committee reverses the expectation of a top-slice. Bill must be devolved to ‘Planning Units’.
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Brian GilmoreComputing Services,University of Edinburgh Edinburgh’s Experiences JISC Charging W/S
Edinburgh - The History • April 98 - University Management Committee reverses the expectation of a top-slice. • Bill must be devolved to ‘Planning Units’. • University Computing Policy Committee refuses to accept bills based on number of ports • Committee also very worried about ‘overheads’ (centrally generated traffic such as email) • Therefore, UKERNA itemisation service had to be used to devolve the bills • July, then August, gave us the first indication of traffic levels to either PUs or central items JISC Charging W/S
August Traffic from the Transatlantic Links JISC Charging W/S
Charged Directly • Direct Departmental Traffic • Charged to Planning Unit (60 in Univ.) or Dept. • just over 80% of the total traffic • Most areas of the University use IP addresses that can be reasonably mapped to their PU • 2 areas have caused difficulties - Medicine & Administration • Some aggregation and network re-numbering is being done. • However, over 750 UKERNA itemisation ‘bins’ are in use (about 120 billing points) JISC Charging W/S
Open Access Labs • Open Access Labs under Computing Services Management. • Not Teaching Labs - they are Departmental. • Academics very reluctant to accept open-ended bills from this area • Very difficult/expensive to tie individual student usage to traffic usage. • Computing Services will bear this charge for the time being (figure will grow in term time). • Intention is to police this area strongly, ie force use of national cache, ban real audio, video etc. JISC Charging W/S
Dialup Traffic • Dialup is a central service run by the Computing Services • Charging individual usage is again very difficult/expensive • Policy body reluctant to carry the charge as an ‘overhead’ unless small • So, force use of national cache etc (90% of browsers will break!) • Some detailed monitoring to stop outright abuse is being performed • Or, seriously consider an annual charge for the service to cover these costs JISC Charging W/S
Central Services • This item covers: • Central email hubs • Central time sharing services • Other centrally managed boxes • Policy body will carry as overhead (so long as it is small!) • Have instituted policy options on central time sharing system which has constrained the traffic JISC Charging W/S
Charged Proxy Caches • We decided to install 2 caches (actually 2x2). One set would be ‘free’ (ie use national cache) and the other charged. • ‘Free’ cache is generating a tiny bill -> overheads • Charged cache (ie: it fetches uncached pages) • Usual problem: what is a fair algorithm for charging? • Fairly arbitrary decision taken: Count the number of requests and divide into the cache bill. Common IP tables used to allocate bill. JISC Charging W/S
Future Challenges • National Caches • When they are no longer free, the itemisation in bills will need to be as good as UKERNA’s! • Our strategy, re ‘restraint of the overhead portion’ will need to be revisited • In particular, students could become a substantial part of the total bill. • Size of the Bill • We are told that the bill will rise substantially - users will question their bills more! • Will need individual itemisation ? JISC Charging W/S