Elektronika 2009-11.pdf - Instytut Systemów Elektronicznych

Fig. 3. Example run of three rounds of i sessions
Rys. 3. Przykładowy przebieg trzech rund z i sesjami
Root is signed by server private key and published:
(6)
There is example run of three rounds of i sessions presented
in Fig. 3.
Geodata authenticity verification
We introduces additional symbol: C i,k - complete to path P i,k (set
of nodes necessary for reconstructing path on the base of d i,last ).
After sending EndSession request client receives from
server information about closing time of current round (time
ct i ). At this pointed moment client sends to server request Get-
SessionProof and gets back information p i necessarry for authenticity
verification of all pairss (q i,j , α i,j ) transmited during
finished session:
(7)
Client reconstructs path from leaf (local copy of f i,k ) to root of
T k tree for i-th session using received complement C i,k . Reconstructed
f’ k root is verified with digital signature:
(8)
Example process of path reconstruction is shown in Fig. 4.
Client wants to verify authenticity of data transmitted during
his 3-th session. It received form server complement C 3,1 =
Fig. 4. Example of P 4,1 path reconstruction
Rys. 4. Przykład rekonstrukcji ścieżki P 4,1
{f 4,1 , f 1:2,1 , f i-3:1,1 }. Client reconstructs f’ 3:4,1 digest from local
copy of digest f’ 3,1 and received digest f 4,1 and continues this
process till obtain root digest f’ 1:i,1 .
Conclusions
The authenticity is today a major problem when dealing with
information transmitted through internet. It’s obvious not every
received data can be trusted. Proposed schema could be successfully
used to publish geodata in authenticated way and to
create proof of their origin. Presented method is simple, safe,
efficient and reliable. It could be easily adapted to into existing
WB GIS architectures.
Implementation of the method should be our next concern.
Currently integration of this schema with Geoserver and
OpenLayers solutions is considered. More examination must
be made to verify methods weaknesses and strengths.
References
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of GIS, pp.1261-1273, Springer 2008.
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[3] Ae Chun S., Alturi V., Geospatial Security Models. Encyclopedia
of GIS, pp. 1028-1035, Springer 2008.
[4] http://www.opengeospatial.org/standards/sld, Open GIS Consortium
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Service Implementation Specification. OpenGIS® Implementation
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20 April 2009.
[5] http://www.opengeospatial.org/standards/wfs, Open GIS Consortium
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OpenGIS® Implementation Specification, Recommendation
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on Advances in cryptology, pp.218-238, Springer-Verlag
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