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Verification of Protocol taDOM2+

For the taDOM2+ 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.
 LRIXIXLevel read intention exclusive: The context node and all its child nodes have been read and at least one descendant (but not a child node) of the context node has been modified.
 SRIXIXSubtree read intention exclusive: The context node and all its descendant nodes have 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.
 LRCXIXLevel read child exclusive: The context node and all its child nodes have been read and at least on child node of the context node has been modified.
 SRCXIXSubtree read child exclusive: The context node and all its descendant nodes have been read and at least on child node of 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:

 -IRNRLRSRIXLRIXSRIXCXLRCXSRCXSUSX
IR+++++++++++--
NR+++++++++++--
LR++++++++-----
SR+++++--------
IX++++-++-++---
LRIX++++-++------
SRIX++++---------
CX+++--+--+----
LRCX+++--+-------
SRCX+++----------
SU+++++--------
SX+------------
Compatibility matrix for taDOM2+
Check of Compatibility Matrix: Ok

Lock Conversion Matrix:

Lock Strength-Relationships:

 IRis stronger thanNR
 NRis stronger thanIR
 LRis stronger thanIR, NR
 SRis stronger thanIR, NR, LR
 IXis stronger thanIR, NR
 LRIXis stronger thanIR, NR, LR, IX
 SRIXis stronger thanIR, NR, LR, SR, IX, LRIX
 CXis stronger thanIR, NR, IX
 LRCXis stronger thanIR, NR, LR, IX, LRIX, CX
 SRCXis stronger thanIR, NR, LR, SR, IX, LRIX, SRIX, CX, LRCX
 SUis stronger thanIR, NR, LR, SR, IX, LRIX, SRIX, CX, LRCX, SRCX, SX
 SXis stronger thanIR, NR, LR, SR, IX, LRIX, SRIX, CX, LRCX, SRCX, SU

 -IRNRLRSRIXLRIXSRIXCXLRCXSRCXSUSX
IRIRIRNRLRSRIXLRIXSRIXCXLRCXSRCXSUSX
NRNRNRNRLRSRIXLRIXSRIXCXLRCXSRCXSUSX
LRLRLRLRLRSRLRIXLRIXSRIXLRCXLRCXSRCXSUSX
SRSRSRSRSRSRSRIXSRIXSRIXSRCXSRCXSRCXSRSX
IXIXIXIXLRIXSRIXIXLRIXSRIXCXLRCXSRCXSXSX
LRIXLRIXLRIXLRIXLRIXSRIXLRIXLRIXSRIXLRCXLRCXSRCXSXSX
SRIXSRIXSRIXSRIXSRIXSRIXSRIXSRIXSRIXSRCXSRCXSRCXSXSX
CXCXCXCXLRCXSRCXCXLRCXSRCXCXLRCXSRCXSXSX
LRCXLRCXLRCXLRCXLRCXSRCXLRCXLRCXSRCXLRCXLRCXSRCXSXSX
SRCXSRCXSRCXSRCXSRCXSRCXSRCXSRCXSRCXSRCXSRCXSRCXSXSX
SUSUSUSUSUSUSXSXSXSXSXSXSUSX
SXSXSXSXSXSXSXSXSXSXSXSXSXSX
Conversion matrix for taDOM2+
Check of Conversion Matrix: Ok