[Gzz-commits] gzz/Documentation/misc/hemppah-progradu mastert...

[Hermanni Hyytiälä]

CVSROOT:        /cvsroot/gzz
Module name:    gzz
Changes by:     Hermanni Hyytiälä <address@hidden>      03/02/24 08:24:41

Modified files:
        Documentation/misc/hemppah-progradu: masterthesis.tex 
                                             progradu.bib 

Log message:
        Text about hash trees

CVSWeb URLs:
http://savannah.gnu.org/cgi-bin/viewcvs/gzz/gzz/Documentation/misc/hemppah-progradu/masterthesis.tex.diff?tr1=1.63&tr2=1.64&r1=text&r2=text
http://savannah.gnu.org/cgi-bin/viewcvs/gzz/gzz/Documentation/misc/hemppah-progradu/progradu.bib.diff?tr1=1.80&tr2=1.81&r1=text&r2=text

Patches:
Index: gzz/Documentation/misc/hemppah-progradu/masterthesis.tex
diff -u gzz/Documentation/misc/hemppah-progradu/masterthesis.tex:1.63 
gzz/Documentation/misc/hemppah-progradu/masterthesis.tex:1.64
--- gzz/Documentation/misc/hemppah-progradu/masterthesis.tex:1.63       Mon Feb 
24 07:21:37 2003
+++ gzz/Documentation/misc/hemppah-progradu/masterthesis.tex    Mon Feb 24 
08:24:41 2003
@@ -1516,8 +1516,10 @@
 we define our objectives and special needs and consider possible
 benefits over existing Peer-to-Peer filesharing systems. Finally, we
 evaluate different peer-to-peer systems with regard to Gzz, make 
-initial analsysis and discuss possible problems.
-
+initial analsysis and discuss possible problems. In the following
+sections, we don't respond security issues. In fact, we assume 
+that system has a working distributed Public Key Infrastructure
+for identifying invidual entities.
 
 
 Fething videos, pictures, music and other media:
@@ -1548,9 +1550,12 @@
    
    
    
-   \cite{mohr02thex}
+   
    \cite{overneturl}
    \cite{edonkey2kurl}
+   
+   \cite{bittorrenturl}
+\cite{maymounkov03ratelesscodes}
 
 \section{Overview}
 
@@ -1638,38 +1643,23 @@
 for identifying scroll blocks. Of course, Peer-to-Peer infrasctructure has to 
be 
 scalable, efficient, adaptive, robust, self-organising and resistant againts 
DDoS 
 attacks. Additionally, if possible, it would be benefitial if Peer-to-Peer 
system 
-would represent all named resources keys.
-
-
-
-
+would represent all named resources as keys.
 
-Gzz's requirements
--append-and-delete (when a modification has been commited, a new version must 
be created)
--the same data block can be stored to many different locations (can we use 
'How share a secret ?', like in Publius and Tangler ?)
--old version(s) must remain accessible in the network
--must support xanalogical structure
--links must work always
--*selective* replication/synking
--do we have a support for transcopyright ?
-
-
-
-
-P2P network requirements
--system must find the service, if it exists in the network
--following properties: scalable, efficient, adaptive, robust, self-organising
--is possible, it would be benefitial if p2p system representing named 
resources as keys 
--p2p system must support the use of block IDs (SHA-1) and urn-5s (random 
string) when obtaining data from the network
--one or more blocks are associated with a specific urn-5
--support for location independent routing (urn-5 -> block(s))
--data block can represent a link, document/part of document, transclusion
--must perform well under DDoS attacks
+\section{Benefits over existing Peer-to-Peer file sharing systems}
 
-\cite{bittorrenturl}
-\cite{maymounkov03ratelesscodes}
+Since Storm uses SHA-1 hash function for creating globally unique
+identifiers, if necessary, we can check the integrity of a scroll
+block by re-computing hash value for a scroll block, once fetched
+form the network. Indeed, all scroll blocks' identifiers are
+self-certifying. However, this not very efficient when we want
+fetch large amounts of data. One possibility is to use tree-based
+hash techiques (e.g., \cite{merkle87hashtree}, \cite{\cite{mohr02thex}) 
+for more efficient data fetcing. Tree based hash functions can be used 
+to verify fixed length segments of data file, instead of whole data file. 
+Currently, Shareaza \cite{shareazaurl}, Overnet \cite{overneturl} and 
+eDonkey2000 \cite{edonkey2kurl} uses tree based hashing for validating 
+segments of a data file.
 
-\section{Benefits over existing Peer-to-Peer file sharing systems}
 
 - Easy syncing:
   - Just copy a bunch of blocks
Index: gzz/Documentation/misc/hemppah-progradu/progradu.bib
diff -u gzz/Documentation/misc/hemppah-progradu/progradu.bib:1.80 
gzz/Documentation/misc/hemppah-progradu/progradu.bib:1.81
--- gzz/Documentation/misc/hemppah-progradu/progradu.bib:1.80   Mon Feb 24 
07:21:37 2003
+++ gzz/Documentation/misc/hemppah-progradu/progradu.bib        Mon Feb 24 
08:24:41 2003
@@ -1945,3 +1945,11 @@
        howpublished = 
{http://open-content.net/specs/draft-jchapweske-thex-01.html}
 }
 
address@hidden,
+       author = {R. C. Merkle},
+       title = {A digital signature based on a conventional encryption 
function},
+       booktitle = {Advances in Cryptology ({CRYPTO'87})},
+       year = {1987},
+       pages = {369--378}
+}
+