Case 5:18-cv-05198-BLF Document 14-2 Filed 10/04/18 Page 1 of 63
`Case 5:18—cv-05198—BLF Document 14-2 Filed 10/04/18 Page 1 of 63
`
`EXHIBIT 2
`EXHIBIT 2
`
`

`

`Case 5:18-cv-05198-BLF Document 14-2 Filed 10/04/18 Page 2 of 63
`
`ilililillllilil lllil lilillill lllll lllll lllll lllll llll lllll lll llll llll
`us00692844282
`1ro; Patcnt No.: US 6,928,442 82
`(+s) Date of Patent: Aug. 9,2005
`
`FOREIGN PAIENT DOCUMENTS
`
`EP
`
`0592045
`
`411994
`
`OTHER PUBLICATIONS
`
`Gwertzman, James, et al. "The Case for Geographical Push-
`Caching." Techlical Reporl I{U TR 34-94 (excerpt), Har-
`vard University, DAS, Cambridge, MA 02138, 1994,2 pgs.
`Grigni, Michelangelo, et a1. "Tight Bounds on Minimum
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`Computcr Systems, vol. 8, No. 2,May 1990, pp. 85-110.
`
`(Continued)
`
`ABSTRACT
`
`Prinary Examiner-1tke S Wossum
`Assistant Examiner--Xhanh Pham
`(74) Anorney, Agert, or Ftnn--Javidson Berquist Jackson
`& Gowdey, l.l,P
`(s7)
`Data files are distributed across a plurality of computers. The
`computers may form a network such as a conlent delivery
`network (CDN) or a peer-to-peer network. The network may
`operate as a TCP/IP network such as the Internet. Data files
`may represent may rcpresenl digital messages, images,
`videos or audio signals. For content--{ala items or liles in
`the systcm-a namc is obtained (or dctcrmincd), wherc lhc
`name is basecl, at least in part, on a given funclion of the data
`in a data item or fi1e. The given function may be a message
`digest or hash function, and it may be MD4, MD5, and SHA.
`A cony of a requested fi1e is only provided to licensed (or
`authorized) parties. The system may check one or more
`computers for unauthorized or unlicensed contenl. Content
`is served based on a measure of availability of servers.
`
`56 Claims, 31 Drawing Sheets
`
`('z) United States Patent
`Farber et al.
`
`(s4) ENFORCEMENT AND POLICING OF
`I,ICENSED CONTENT USING
`CONTENT-BASED IDENTIFIERS
`(75) lnventors: David A. Farber, Ojai, (lA (US);
`Ronnld l). Lachman, Norlhbrook, IL
`(US)
`(73) Assignees: Kinetech, Inc., Northbrook, IL (US);
`Savviq Inc,,'lirwn & (buntry, Mo
`(US)
`( - ) Notice: Subject to any disclaimer, the term ofthis
`patent is extended or adiusted uncler 35
`U.S.C. 154(b) by 0 days.
`
`(21) Appl. No.: 091987,723
`(22) Filed: Nov. 15' 2001
`(65)
`Prior Publicntion l)atrr
`IJS 200210052&34 Al May 2,2002
`
`Related U.S. ApPlication Data
`
`(63) Continuation of application No. 091283,160. filed on Apr. 1,
`1999, now Pat. No. 6.41.5.280, which is a division of
`application No. 08i960,079, filed on Oct. 24, 1991. now Pat'
`No. -s.qlS,Zql, which is a continuation of application No.
`Ct81425,160, filcd on Apr. 11. 1995, now abandoned.
`Int. Cl.7
`G06F 17130
`7 07 I lO; 7 07 I 3; 7 O7 I I0I;
`u.s. ct.
`7 07 l2o0; 7 09 203 ; 7 09 l2t9 ; 709 1229
`(58) Field of Search
`70713,6,9, rO,
`707 l lC1, 2OO: 709 t203. 2 19. 229
`
`(s1)
`(s2)
`
`(s6)
`
`References Cited
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`(Continued)
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`A AA A
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`3,668,647
`4,215,402
`4,290,705
`4,376,299
`4,405,829
`4.412,28s
`
`","I
`
`DAfA I|EM
`
`COMPUTE''D FUNCTION ON
`DAIA TTEM
`
`LENGTH MODULO 12 OF
`DATA IIEM
`
`It
`
`EXHIBIT 2 . 1
`
`

`

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`12/'1984
`2/1986
`j1 1986
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`211988
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`121.989
`121 1989
`51990
`5,11990
`1t/1990
`61991.
`911991.
`91991.
`10,i 1sq1
`t2lr9q1
`'tll992
`'711992
`9 1992
`l/t993
`4L993
`5//199-3
`1/1994
`211994
`4/1994
`4/1994
`811994
`8/r994
`10/1994
`1/t995
`4/1995
`9/1995
`70/1995
`7/1996
`12/1996
`6/199'7
`6/ 1997
`7/1998
`9/1998
`9/ 1998
`11/1998
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`t2/1999
`10/2000
`
`Sumnrer,.Ir.
`Fletcher
`Benhase
`Dixon
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`Meaden
`Gmner
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`Bendert
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`Colwell
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`
`A
`
`A AAA AA AA AA A A A
`
`AA AAAAA A AA AA
`
`4.414.624
`4,441,155
`4,464,113
`4"490,"182
`4,57t,700
`4,57'7,293
`4,642,793
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`

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`
`EXHIBIT 2 - 3
`
`

`

`Case 5:18-cv-05198-BLF Document 14-2 Filed 10/04/18 Page 5 of 63
`
`LJ.S. Patent
`
`Aug. 9,2005 Sheet 1 of 31
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`us 6,928,442 B2
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`Case 5:18-cv-05198-BLF Document 14-2 Filed 10/04/18 Page 6 of 63
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`LJ,S. Patent
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`Aug. 9,2005 Sheet 2 of 3l
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`Case 5:18-cv-05198-BLF Document 14-2 Filed 10/04/18 Page 7 of 63
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`Case 5:18-cv-05198-BLF Document 14-2 Filed 10/04/18 Page 8 of 63
`
`LJ.S. Patent
`
`Aug. 9,2005 Sheet 4 of 31
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`us 6,928,442 B2
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`FIG.3
`ion ID
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`access
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`EXHIBIT 2 - 7
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`

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`Case 5:18-cv-05198-BLF Document 14-2 Filed 10/04/18 Page 9 of 63
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`EXHIBIT 2 - 8
`
`

`

`Case 5:18-cv-05198-BLF Document 14-2 Filed 10/04/18 Page 10 of 63
`
`LJ.S. Patent
`
`Aug. 9,2005 Sheet 6 of 31
`
`us 6,928,442 82
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`EXHIBIT 2 . 9
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`SIM
`DATA ITEM
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`12
`COMPUTE MD FUNCTION ON
`DATA ITEM
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`tI I I I I II Il II IIII IItIII III
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`

`

`Case 5:18-cv-05198-BLF Document 14-2 Filed 10/04/18 Page 11 of 63
`
`LJ.S. Patent
`
`Aug. 9, 2005 Sheet 7 of 31
`
`us 6,928,442 82
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`s216
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`EXHIBIT 2 - IO
`
`

`

`Case 5:18-cv-05198-BLF Document 14-2 Filed 10/04/18 Page 12 of 63
`
`LJ.S. Patent
`
`Aug. 9,2005 Sheet 8 of 31
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`Case 5:18-cv-05198-BLF Document 14-2 Filed 10/04/18 Page 13 of 63
`
`IJ.S. Patent
`
`Aug. 9,2005 Sheet 9 of 31
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`us 6,928,442 B2
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`Case 5:18-cv-05198-BLF Document 14-2 Filed 10/04/18 Page 14 of 63
`
`[I.S. Patent
`
`Aug. 9,2005 Sheet 10 of 31
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`us 6,928,442 82
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`

`

`Case 5:18-cv-05198-BLF Document 14-2 Filed 10/04/18 Page 15 of 63
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`LJ.S. Patent
`
`Aug. 9, 2005 Sheet 11 of 31
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`

`

`Case 5:18-cv-05198-BLF Document 14-2 Filed 10/04/18 Page 16 of 63
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`Aug. 9,2005 Sheet 12 of 31
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`Case 5:18-cv-05198-BLF Document 14-2 Filed 10/04/18 Page 17 of 63
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`Aug. 9,2005 Sheet 13 of 31
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`Case 5:18-cv-05198-BLF Document 14-2 Filed 10/04/18 Page 18 of 63
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`LJ.S. Patent
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`Aug. 9,2005 Sheet 14 of 31
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`Case 5:18-cv-05198-BLF Document 14-2 Filed 10/04/18 Page 19 of 63
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`Aug. 9,2005 Sheet 15 of 31
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`Case 5:18-cv-05198-BLF Document 14-2 Filed 10/04/18 Page 20 of 63
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`Case 5:18-cv-05198-BLF Document 14-2 Filed 10/04/18 Page 21 of 63
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`Case 5:18-cv-05198-BLF Document 14-2 Filed 10/04/18 Page 22 of 63
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`Case 5:18-cv-05198-BLF Document 14-2 Filed 10/04/18 Page 23 of 63
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`Aug. 9,2005 Sheet 19 of 31
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`Case 5:18-cv-05198-BLF Document 14-2 Filed 10/04/18 Page 24 of 63
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`Aug. 9,2005 sheet 20 of 31
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`Case 5:18-cv-05198-BLF Document 14-2 Filed 10/04/18 Page 25 of 63
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`LJ.S. Patent
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`Aug. 9,2005 Sheet 21 of 3l
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`Case 5:18-cv-05198-BLF Document 14-2 Filed 10/04/18 Page 26 of 63
`
`LJ.S. Patent
`
`Aug. 9,2005 Sheet 22 of 3l
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`us 6,928,442 82
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`EXHIBIT 2 .25
`
`

`

`Case 5:18-cv-05198-BLF Document 14-2 Filed 10/04/18 Page 27 of 63
`
`[I.S. Patent
`
`Aug. 9,2005 Sheet 23 of 3l
`
`us 6,928,442 82
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`EXHIBIT 2 - 26
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`

`

`Case 5:18-cv-05198-BLF Document 14-2 Filed 10/04/18 Page 28 of 63
`
`LJ.S. Patent
`
`Aug. 9,2005 Sheet 24 of 3l
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`us 6,928,442 82
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`EXHIBIT 2 - 27
`
`

`

`Case 5:18-cv-05198-BLF Document 14-2 Filed 10/04/18 Page 29 of 63
`
`LJ.S. Patent
`
`Aug. 9,2005 Sheet 25 of 31
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`us 6,928,442 82
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`EXHIBIT 2 - 28
`
`

`

`Case 5:18-cv-05198-BLF Document 14-2 Filed 10/04/18 Page 30 of 63
`
`LJ.S. Patent
`
`Aug. 9,2005 Sheet 26 of 31
`
`us 6,928,442 82
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`EXHIBIT 2 - 29
`
`

`

`Case 5:18-cv-05198-BLF Document 14-2 Filed 10/04/18 Page 31 of 63
`
`IJ.S. Patent
`
`Aug. 9,2005 Sheet 27 of 31
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`Case 5:18-cv-05198-BLF Document 14-2 Filed 10/04/18 Page 32 of 63
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`Aug. 9,2005 Sheet 28 of 31
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`Case 5:18-cv-05198-BLF Document 14-2 Filed 10/04/18 Page 33 of 63
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`LJ.S. Patent
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`Aug. 9,2005 Sheet 29 of 3l
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`us 6,928,442 82
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`

`Case 5:18-cv-05198-BLF Document 14-2 Filed 10/04/18 Page 34 of 63
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`LJ.S. Patent
`
`Aug. 9,2005 Sheet 30 of 31
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`Case 5:18-cv-05198-BLF Document 14-2 Filed 10/04/18 Page 35 of 63
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`Aug. 9,2005 sheet 31 of 31
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`Case 5:18-cv-05198-BLF Document 14-2 Filed 10/04/18 Page 36 of 63
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`us 6,928,442 B2
`
`I
`I,NFORCEMBNT AND POLICING OF
`LICENSBD CONTENT USING CONTBNT-
`BASED IDENTIFIERS
`
`This is a continuation of application Scr. No. 091283,160,
`filed Apr. I, 1999, nou'U.S. Pat. No. 6,415,280, which is a
`division of application Ser. No. 08/960,079, filed Oct. 24,
`1997, now U.S. Pat. No. 5,918,791liled Oc1. 24, 2001 which
`is a continuation of Ser. No. 081425,160, filed Apr. 11, 19S5,
`now abandoned.
`
`BACKGROUND OF THE INVENTION
`1. Field of the Invenlion
`'lhis invention relates to data processing syslems and,
`more particularly, 1o data proccssing systcms whcrcin data
`items are identified by substantially unique identifiers which
`depend on a1i of the dala in lhe data items and only on the
`data in the data items.
`2. Background of the Invention
`Dala processing (DP) systems, compulers, networks of
`computers, or the 1ike, typically offer users and programs
`various ways to identity the clata in the systems.
`Users typically identify data in the data processing system
`by giving the data some form of name. For example, a
`typical operating system (OS) on a computer provides a lile
`system in which data items are named by alphanumeric
`identifiers. Programs typically identify data in the data
`processing systcm using a location or address. For cxamplc,
`a program may identiS, a record in a file or database by using
`a record number which serves to locate lhat record.
`In all but the most primitive operating systems, users and
`programs are able to creale and use collections of named
`data ilems, these colleclions themselves being named by
`identifiers. These named collections can then, themselves,
`tre made part of other named collections. For example, an
`OS may provicle mechanisms to group files (data items) into
`directories (colleclions). These directories can then, them-
`selves be made parl of other directories. A data item may
`thus be idcntificd rclativc to thesc ncstcd dircctorics using a
`sequence of names, or a so-called pathname, which defines
`a path through the directories to a particular data item (file
`or directory).
`As another example, a dalabase management system may
`group data records (data items) into tables and then group
`these tables into database files (collections). The complete
`addrcss of any data rccord can thcn bc specifled using the
`database flle name, the table name, and the record number of
`that clala record.
`Other examples of idenlifying data items include: identi-
`fying liles in a netrvork lile system, identilying objects in an
`objecl-oriented database, identifying images in an image
`databasc, and identifying articlcs in a text databasc.
`In general, thc terms "data" and "data ilcm" as uscd hcrein
`refer to sequences of bits. Thus a data item may be the
`contents of a flle, a portion of a file, a page in memory, an
`object in an object-orientecl program, a digital message, a
`digital scanned image, a part ol a video or audio signal, or
`any other entity which can be represented by a sequence of
`bits. The tcrm "data processing" hercin rcfers to thc pro-
`cessing of data items, and is somelimes dependent on the
`type of data item being processed. For example, a dala
`pncessor for a digital image may differ lrom a dala pro-
`cessor ibr an auclio signal.
`In all of the prior data processing syslems lhe names or
`identiliers provided to identifu data items (the data items
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`being files, directories, records in the clatatrase, otrjects in
`object-oriented programming, locations in memory or on a
`physical device, or the like) are always defined relalive to a
`specific context. For instance, the fi1e identified by a par-
`s ticular file name can only be delermined wlien the directory
`containing the Iile (the context) is known. The lile iclenlifled
`by a pathname can be determined only when the lile system
`(context) is known. Simiiarl,v, thc addrcsscs in a proccss
`address space, the keys in a database tab1e, or domain names
`i0 on a globai compuler network such as the Internet are
`meaningful only because they are specilied relative to a
`conlext.
`In prior art syslems for identifying data items lhere is no
`direct relationship between the data names and the clata iten-r.
`The same clata name in two different contexts may refer to
`differenl data ilems. and two different data names in the
`samc contcxl may rcfcr lo thc samc dala ilcm.
`In addition, because there is no correlation between a dala
`name and the data it rel'ers to, there is no a priori way ttl
`conlirm that a given data ilem is in fact the one named lry a
`data namc. For instancc, in a DP systcm, if onc proccssor
`requests that another processor deliver a data item with a
`given data name, the requesting processor cannot, in
`general, verify that the dala delivered is lhe correct data
`(given only the name). Therefore it may require ftrrther
`processing, typically on the part of the requesler, lo verify
`that the data item it has obtained is, in fact, the item it
`requcstecl.
`A common operation in a I)P system is adding a new data
`item to the system. When a new data item is aclded to the
`system, a name can be assigned to it only by updating the
`context in which names are deflned. Thus such systems
`require a centralized mechanism for the management of
`names. Such a mechanism is required even in a multi-
`processing system rl'hen data items are created and identified
`at separale processors in distincl locations, and in s'hich
`there is no other need for communication when data items
`are added.
`In many data processing systems or environments, data
`items are transfered lrelween different localions in the
`system. These locations may be processors in the data
`processing system, storage devices, memory, or the like. For
`example, one processor may obtain a data item from another
`processor or from an external storage device, such as a
`floppy disk, and may incorporate that data item into its
`system (using the name provided u,ith thal data ilem).
`However, when a pr<rcessor (or some krcatitln) obtains a
`data ilem fiom another location in the DP system, il is
`possiblc that this obtaincd data item is already prcscnt in thc
`system (either at the location of the processor or at some
`olher location accessible by the processor) and therefore a
`duplicate of the data ilem is created. This situation is
`common in a nelq,ork data processing environmenl where
`propriclary soflu,arc products are installcd from floppy disks
`onto several processors sharing a common flie server. In
`these systems, it is often the case that the same product will
`be installed on several systems, so that several copies of
`each Iile will reside <in the common Ille server.
`ln some dala processing systems in which several pro-
`cessors are connected in a network, one system is designated
`as a cachc server to mainlain master copics of data items,
`and other systems are designated as cache clients to copy
`local copies of the master data items into a local cache on an
`as-needed basis. Before using a cached item, a cache client
`must either reload the cached item, be infbrmed of changes
`to the cached item, or confirm thal lhe master item corre-
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`sponding to the cached item has not changed. In other rvords,
`a cache c1ienl must synchronize its dala items with those on
`the cache server. This synchronization may involve reload-
`ing clata items onto the cache client. The need to keep tlre
`cache synchronized or reload it adds significant overheacl to s
`existing caching mechanisms.
`In view of the above and other problems with prior art
`systcms, it is thcrcfore dcsirablc to havc a mcchanism which
`ailows each processor in a multiprocessor system to deter-
`mine a common and subslantialiy unique identifier for a data 10
`item, using onlv the clala in the data item and not relying on
`any sort of context.
`Il is further desirable to have a mechanism for reclucing
`multiple copies of data items in a dala processing system and
`to have a mechanism which enablei the iclentification of 15
`identical data items so as to reduce mulliple copies. It is
`further desirable to determine *.hether trvo instances of a
`data item are in fact the same data item, and lo perform
`various olher systems' lunctions and applications on dala
`ilems rvithout rellng on any conlext intbrmation o. p.op- 20
`crtics of thc data itcm.
`It is also desirable lo provide such a mechanism in such
`a way as 1o make it transparent to users oi the data
`processing system, and it is desirable that a single mecha- ^.
`nism bc used to addrcss cach of thc problcms dcscribcd
`above.
`
`SUMMARY OF TTIE INVT,NTION
`This invention provides, in a clata processing system, a
`method and apparatus for iclentifying a data item in tbe
`system, where the identity of the clata ilem depends on all of
`the data in the dala item and only on the data in the dala item.
`Thus the identity of a clata item is independent of its name,
`origin, location, addrcss, or othcr informalion not dcrivablc
`directly from the da1a, and depends only on the data itself.
`This invention further provides an apparalus and a method
`for determining whether a particular data item is present in
`the system or at a location in the system, by examining only
`the data identities ol a plurality of data items.
`Using the method or apparatus of the present invention,
`the efficiency and integrity of a data processing system can
`be improvcd. The prescnt invention improvcs thc design and
`operation of a data slorage system, fi1e system, relational
`database, object-oriented database, or the like lhal stores a
`plurality of data items, by making possible or improving the
`design and operation of at leasl some or all of the following
`features:
`the system stores at mosl one copy of any data item at a
`given iocation, evcn whcn multiple data namcs in the
`system refer to