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

[Hermanni Hyytiälä]

CVSROOT:        /cvsroot/gzz
Module name:    gzz
Changes by:     Hermanni Hyytiälä <address@hidden>      03/02/05 06:50:09

Modified files:
        Documentation/misc/hemppah-progradu: progradu.bib 
                                             research_problems 

Log message:
        Security issues

CVSWeb URLs:
http://savannah.gnu.org/cgi-bin/viewcvs/gzz/gzz/Documentation/misc/hemppah-progradu/progradu.bib.diff?tr1=1.62&tr2=1.63&r1=text&r2=text
http://savannah.gnu.org/cgi-bin/viewcvs/gzz/gzz/Documentation/misc/hemppah-progradu/research_problems.diff?tr1=1.40&tr2=1.41&r1=text&r2=text

Patches:
Index: gzz/Documentation/misc/hemppah-progradu/progradu.bib
diff -u gzz/Documentation/misc/hemppah-progradu/progradu.bib:1.62 
gzz/Documentation/misc/hemppah-progradu/progradu.bib:1.63
--- gzz/Documentation/misc/hemppah-progradu/progradu.bib:1.62   Fri Jan 31 
04:33:29 2003
+++ gzz/Documentation/misc/hemppah-progradu/progradu.bib        Wed Feb  5 
06:50:09 2003
@@ -827,7 +827,7 @@
        publisher = {ACM Press},
 }
 
-%Feasibility studie of DFS on desktop PCs
+%Feasibility studie of DFS on desktop PCs: Farsite
 @inproceedings{339345,
  author = {William J. Bolosky and John R. Douceur and David Ely and Marvin 
Theimer},
  title = {Feasibility of a serverless distributed file system deployed on an 
existing set of desktop PCs},
Index: gzz/Documentation/misc/hemppah-progradu/research_problems
diff -u gzz/Documentation/misc/hemppah-progradu/research_problems:1.40 
gzz/Documentation/misc/hemppah-progradu/research_problems:1.41
--- gzz/Documentation/misc/hemppah-progradu/research_problems:1.40      Fri Jan 
31 04:33:29 2003
+++ gzz/Documentation/misc/hemppah-progradu/research_problems   Wed Feb  5 
06:50:09 2003
@@ -1,3 +1,7 @@
+
+We (footonote)
+footnote:use of the plural is customary even if research paper is authored 
solely
+
 1. Approaches
 
 -there are five approaches when performing searches in p2p networks.
@@ -36,7 +40,8 @@
 -Of couse, there is the possibility to route in constant times, but it 
requires that *each** node
 maintains information about all the nodes in the network. Therefore , 
practically, this method 
 impossible
--Example systems: Chord, CAN, Kademlia, Pastry, Tapestry, Viceroy
+-Example systems: Chord, CAN, Kademlia, Pastry, Tapestry, Viceroy, Symphony, 
SkipNet, Skip Graph
+-Example applications: CFS, PAST, Oceanstore
 
 *Update*
 -Viceroy system achieves O(log n) hops with only O(1) neighbors
@@ -1063,10 +1068,26 @@
  
 5.6. Attack models/behavior of faulty nodes
 
-1) Sybil attack \cite{douceur02sybil}
+1) Sybil attack \cite{douceur02sybil} 
 2) Fail-stop
 3) Spam generating model \cite{naor03simpledht}
 4) Byzantine problem \cite{357176}, p2p domain \cite{296824}
+
+Solutions for Sybil Attack: 
+1) data replication among several peers
+2) data fragmentation among several peer
+
+BUT: 
+-in either case, both approaches assumes that two different remote entities 
are actually different; sybil attacks are still possible --> need for 
centralized authority
+-in p2p environment, trusting to collective assurance of multiple signatories 
(like PGP) is not safe/undermines the authenticity of system (because of sybil 
attacks)
+-\cite{douceur02sybil} argues that Sybil attacks are always possible except 
under extreme and unrealistic assumptions of resource parity and coordination 
among entities
+
+Current research with regard to p2p security:
+-lot of done has been done on persistence
+-little has been done on distinctness (sybil attack)
+-computational puzzles for preventing DDOS attacks (force attacker perform 
more work than victim)
+-puzzles can be used for accountability (Dingeline, in Peer-to-Peer: 
Harnessing...), but can dangerous
+-some research has been done on on-line identities for humans. However, they 
often has a direct relation to phychical world