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Verification of Protocol taDOM3

For the taDOM3 locking protocol the following locks are used:

 Lock on
Context Node
Lock on
Parent Node
Description
 IRIRIntention read: At least one descendant of the context node has been read.
 NRIRNode read: The context node has been read.
 LRIRLevel read: The context node and all its child nodes have been read.
 SRIRSubtree read: The context node and all its descendants have been read.
 IXIXIntention exclusive: At least one descendant node (but not a child node) of the context node has been modified.
 NRIXIXNode read intention exclusive: The context node has been read and at least one descendant (but not a child node) of the context node has been modified.
 CXIXChild exclusive: At least on child node of the context node has been modified.
 NRCXIXNode read child exclusive: The context node has been read and at least on child node of the context node has been modified.
 NUIRNode update: The context node has been read. Possible downgrade to NR or upgrade to NX.
 NXCXNode exclusive: The context node has been modified.
 SUIRSubtree update: The context node and all its descendant nodes have been read. Possible downgrade to SR or upgrade to SX.
 SXCXSubtree exclusive: The context node and all its descendants are locked for deletion.

Lock Compatibility Matrix:

 -IRNRLRSRIXNRIXCXNRCXNUNXSUSX
IR+++++++++++--
NR+++++++++----
LR+++++++------
SR+++++--------
IX++++-++++++--
NRIX++++-++++----
CX+++--++++++--
NRCX+++--++++----
NU+++++++++----
NX++---+-+-----
SU+++++--------
SX+------------
Compatibility matrix for taDOM3
Check of Compatibility Matrix: Ok

Lock Conversion Matrix:

Lock Strength-Relationships:

 IRis stronger thanno other lock
 NRis stronger thanIR
 LRis stronger thanIR, NR
 SRis stronger thanIR, NR, LR
 IXis stronger thanIR
 NRIXis stronger thanIR, NR, IX
 CXis stronger thanIR, IX
 NRCXis stronger thanIR, NR, IX, NRIX, CX
 NUis stronger thanIR, NR, IX, NRIX, CX, NRCX, NX
 NXis stronger thanIR, NR, IX, NRIX, CX, NRCX, NU
 SUis stronger thanIR, NR, LR, SR, IX, NRIX, CX, NRCX, NU, NX, SX
 SXis stronger thanIR, NR, LR, SR, IX, NRIX, CX, NRCX, NU, NX, SU

 -IRNRLRSRIXNRIXCXNRCXNUNXSUSX
IRIRIRNRLRSRIXNRIXCXNRCXNUNXSUSX
NRNRNRNRLRSRNRIXNRIXNRCXNRCXNRNXSUSX
LRLRLRLRLRSRNRIXNRNRIXNRNRCXNRNRCXNRNUNRNXNRSUSX
SRSRSRSRSRSRNRIXSRNRIXSRNRCXSRNRCXSRNUSRNXSRSRSX
IXIXIXNRIXNRIXNRNRIXSRIXNRIXCXNRCXNXNXSXSX
NRIXNRIXNRIXNRIXNRIXNRNRIXSRNRIXNRIXNRCXNRCXNXNXSXSX
CXCXCXNRCXNRCXNRNRCXSRCXNRCXCXNRCXNXNXSXSX
NRCXNRCXNRCXNRCXNRCXNRNRCXSRNRCXNRCXNRCXNRCXNXNXSXSX
NUNUNUNUNUNRNUSRNXNXNXNXNUNXSUSX
NXNXNXNXNXNRNXSRNXNXNXNXNXNXSXSX
SUSUSUSUSUSUSXSXSXSXSUSXSUSX
SXSXSXSXSXSXSXSXSXSXSXSXSXSX
Conversion matrix for taDOM3
Check of Conversion Matrix: Ok