[clug] Wildly OT: NetApp patents for "Write Anywhere File Layout" (snapshots)

[steve jenkin]

There are enough kernel developers, hackers and FOSS people on this list
that the following might be of interest.

  WAFL & its side-effect, snapshots, was as radical advance in
  filesystems as RAID - a provably perfect backup/rollback
  mechanism for transactional filesystems (eg. DB's),
  whilst overcoming the obvious "copy on write" problem.

Discussion point:
=> Should've NetApp been granted a monopoly on the idea
   for 17-20 years?? i.e. at least until 2012.
   If not, then how should they have been allowed to gain
   from their great idea/work, or get a monopoly for how long?

I was surprised there were so few (4) patents on WAFL.
NetApp has a total of 322 patents assigned to it.

If you look at the patents, the lists of References to Prior Art are
impressive :-)

<http://patft.uspto.gov/>

advanced search term:
 an/("Network Appliance, Inc") and ttl/(file and layout)

1 7,430,571	Extension of write anywhere file layout write allocation
2 7,409,494	Extension of write anywhere file system layout
3 6,289,356	Write anywhere file-system layout
4 5,963,962	Write anywhere file-system layout

related patents
  5,819,292	Method for maintaining consistent states of a
		file  system and for creating user-accessible
		read-only copies of a file system

	-> 5,819,292 is 'related' to Application 71643, Jun., *1993*
	-> 6,289,356 is referenced by  *95* patents
	-> 5,963,962 is referenced by *169* patents
	-> 5,819,292 is referenced by *245* patents
	   advanced search terms (pick one):
		ref/6289356 ref/5963962 ref/5819292

5,819,292 filed May 31, 1995,		granted October 6, 1998
5,963,962 filed June 30, 1998,		granted October 5, 1999
6,289,356 filed September 14, 1998,	granted September 11, 2001
7,409,494 filed April 30, 2004,		granted August 5, 2008
7,430,571 filed April 30, 2004,		granted September 30, 2008

-- 
Steve Jenkin, Info Tech, Systems and Design Specialist.
0412 786 915 (+61 412 786 915)
PO Box 48, Kippax ACT 2615, AUSTRALIA

sjenkin at canb.auug.org.au http://members.tip.net.au/~sjenkin