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Secure Distributed Open  Social  Networks ,[object Object],[object Object],[object Object],[object Object],[object Object],photo by prakharevich
Overview ,[object Object],[object Object],[object Object],[object Object],[object Object]
Too many Social Networks? ...are there too many web servers?
The Problem: data silos ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]
Scoble gets thrown off Facebook! In early January 2008 Scoble, the developer who got blogging going at Microsoft, got thrown off Facebook for extracting information too agressively from his social network on Facebook. This is the Facebook who asked users for their gmail password to extract all their contacts from their email! see  his video
An (evolving) Social Graph ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]
Two social Networks how can Tim and Henry link up ?
Solution 1: minimal naïve approach but within each SN queries are very limited: e.g.: in Network A, nobody can query for Tim's address
Solution 2: copy some information ,[object Object],[object Object],[object Object]
Solution 3: copy all ,[object Object],[object Object],[object Object],[object Object]
The pull to one network Due to  Metcalf's law : the larger the network the more valuable it becomes. But why does it have to be in one database?  Because each database has its own LOCAL POINTER mechanism, just like every Java virtual Machine has a local pointer mechanism. You cannot easily point from one JVM/DB into another. What if we had one big world wide database? we would need universal names for things. URIs?
The Solution: linking across social networks requires a global namespace
The Solution: a closer look ,[object Object],[object Object],[object Object]
A hyperdata Address Book
1. first launch of jnlp
2. drag and drop a foaf file url
3. click on the first name in the first column
4. explore the second column
5. press the space bar on the keyboard...
6. positioning with NASA's World Wind
7.  Sun Intranet Foaf experiment
Foaf: Friend of a Friend
Advantages  ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]
Two foaf files on the internet
Well, what we really have is
Well, what we really have is in graph view
The graphs inside the Beatnik Database
Networked graphs: A merged view
SPARQL: semantic query lang ,[object Object],[object Object],[object Object],[object Object],[object Object]
SPARQL construct query PREFIX xsd: <http://www.w3.org/2001/XMLSchema#> CONSTRUCT { ?subject  ?relation ?object . } WHERE { GRAPH ?g {  ?subject  ?relation ?object . } ?g :fetched-at ?date . FILTER { ?date < “2008-03-30”^^xsd:date } }  This CONSTRUCT query can be used to construct a graph that is a union of all graphs that were fetched after march 2008.
Networked Graphs: SPARQL Rules PREFIX owl: < http://www.w3.org/2002/07/owl #> CONSTRUCT { ?b owl:sameAs ?a . }  WHERE {  ?a owl:sameAs ?b .  FILTER ( ! SAMETERM(?a , ?b) )  }  CONSTRUCT queries can also be thought of as rules. Here is the well known rule of symmetry of identity. Simon Schenk's  Networked Graphs  can have a number of rules expressed as SPARQL CONSTRUCT queries, which works nicely with the Sesame semantic engine.
merging identities PREFIX owl: < http://www.w3.org/2002/07/owl #> PREFIX foaf: < http://xmlns.com/foaf/0.1/ > CONSTRUCT { ?a owl:sameAs ?b .  }  WHERE {  ?a foaf:homepage ?pg . ?b foaf:homepage ?pg . FILTER ( ! SAMETERM (?a , ?b))  }  The rule that if we have two names for people that have the same homepage, then the two names refer to the same person. There are more general ways of stating this btw.
Security: 3 approaches ,[object Object],[object Object],[object Object]
Firewall protection
Protecting resources with OpenId
Protected Resources ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]
OpenId continued
foaf+ssl: even simpler
Protected Resources ,[object Object],[object Object],[object Object],[object Object]
foaf+ssl: even simpler
X509 certificate Certificate: Data: Version: 3 (0x2) Serial Number: 1 (0x1) Signature Algorithm: dsaWithSHA1 Issuer: O=OpenPGP to X.509 Bridge, OU=RDFauth Test, CN=Henry Story <henry.story@bblfish.net> Validity Not Before: Dec 12 21:49:50 2007 GMT Not After : Dec  6 21:49:50 2008 GMT Subject: O=OpenPGP to X.509 Bridge, OU=RDFauth Test, CN=Henry Story <henry.story@bblfish.net> Subject Public Key Info: Public Key Algorithm: dsaEncryption DSA Public Key: pub:  33:41:...
X509 certificate with id X509v3 extensions: X509v3 Basic Constraints: critical CA:TRUE X509v3 Key Usage: critical Digital Signature, Non Repudiation, Key Encipherment, Key Agreement, Certificate Sign Netscape Cert Type:  SSL Client, S/MIME X509v3 Subject Key Identifier:  45:DC:F9:10:33:C0:45:28:EA:90:6E:83:73:06:6F:51:21:89:13:DD X509v3 Authority Key Identifier:  keyid:45:DC:F9:10:33:C0:45:28:EA:90:6E:83:73:06:6F:51:21:89:13:DD X509v3 Subject Alternative Name:  URI:http://bblfish.net/people/henry/card#me Signature Algorithm: dsaWithSHA1 30:2c:02:14:78:69:1e:4f:7d:37:36:a5:8f:37:30:58:18:5a: f6:10:e9:13:a4:ec:02:14:03:93:42:3b:c0:d4:33:63:ae:2f: eb:8c:11:08:1c:aa:93:7d:71:01
Very Simple Authentication
The Semantic Desktop
some references ,[object Object],[object Object]

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Secure Distributed Open Social Networks

  • 1.
  • 2.
  • 3. Too many Social Networks? ...are there too many web servers?
  • 4.
  • 5. Scoble gets thrown off Facebook! In early January 2008 Scoble, the developer who got blogging going at Microsoft, got thrown off Facebook for extracting information too agressively from his social network on Facebook. This is the Facebook who asked users for their gmail password to extract all their contacts from their email! see his video
  • 6.
  • 7. Two social Networks how can Tim and Henry link up ?
  • 8. Solution 1: minimal naïve approach but within each SN queries are very limited: e.g.: in Network A, nobody can query for Tim's address
  • 9.
  • 10.
  • 11. The pull to one network Due to Metcalf's law : the larger the network the more valuable it becomes. But why does it have to be in one database? Because each database has its own LOCAL POINTER mechanism, just like every Java virtual Machine has a local pointer mechanism. You cannot easily point from one JVM/DB into another. What if we had one big world wide database? we would need universal names for things. URIs?
  • 12. The Solution: linking across social networks requires a global namespace
  • 13.
  • 15. 1. first launch of jnlp
  • 16. 2. drag and drop a foaf file url
  • 17. 3. click on the first name in the first column
  • 18. 4. explore the second column
  • 19. 5. press the space bar on the keyboard...
  • 20. 6. positioning with NASA's World Wind
  • 21. 7. Sun Intranet Foaf experiment
  • 22. Foaf: Friend of a Friend
  • 23.
  • 24. Two foaf files on the internet
  • 25. Well, what we really have is
  • 26. Well, what we really have is in graph view
  • 27. The graphs inside the Beatnik Database
  • 28. Networked graphs: A merged view
  • 29.
  • 30. SPARQL construct query PREFIX xsd: <http://www.w3.org/2001/XMLSchema#> CONSTRUCT { ?subject ?relation ?object . } WHERE { GRAPH ?g { ?subject ?relation ?object . } ?g :fetched-at ?date . FILTER { ?date < “2008-03-30”^^xsd:date } } This CONSTRUCT query can be used to construct a graph that is a union of all graphs that were fetched after march 2008.
  • 31. Networked Graphs: SPARQL Rules PREFIX owl: < http://www.w3.org/2002/07/owl #> CONSTRUCT { ?b owl:sameAs ?a . } WHERE { ?a owl:sameAs ?b . FILTER ( ! SAMETERM(?a , ?b) ) } CONSTRUCT queries can also be thought of as rules. Here is the well known rule of symmetry of identity. Simon Schenk's Networked Graphs can have a number of rules expressed as SPARQL CONSTRUCT queries, which works nicely with the Sesame semantic engine.
  • 32. merging identities PREFIX owl: < http://www.w3.org/2002/07/owl #> PREFIX foaf: < http://xmlns.com/foaf/0.1/ > CONSTRUCT { ?a owl:sameAs ?b . } WHERE { ?a foaf:homepage ?pg . ?b foaf:homepage ?pg . FILTER ( ! SAMETERM (?a , ?b)) } The rule that if we have two names for people that have the same homepage, then the two names refer to the same person. There are more general ways of stating this btw.
  • 33.
  • 36.
  • 39.
  • 41. X509 certificate Certificate: Data: Version: 3 (0x2) Serial Number: 1 (0x1) Signature Algorithm: dsaWithSHA1 Issuer: O=OpenPGP to X.509 Bridge, OU=RDFauth Test, CN=Henry Story <henry.story@bblfish.net> Validity Not Before: Dec 12 21:49:50 2007 GMT Not After : Dec 6 21:49:50 2008 GMT Subject: O=OpenPGP to X.509 Bridge, OU=RDFauth Test, CN=Henry Story <henry.story@bblfish.net> Subject Public Key Info: Public Key Algorithm: dsaEncryption DSA Public Key: pub: 33:41:...
  • 42. X509 certificate with id X509v3 extensions: X509v3 Basic Constraints: critical CA:TRUE X509v3 Key Usage: critical Digital Signature, Non Repudiation, Key Encipherment, Key Agreement, Certificate Sign Netscape Cert Type: SSL Client, S/MIME X509v3 Subject Key Identifier: 45:DC:F9:10:33:C0:45:28:EA:90:6E:83:73:06:6F:51:21:89:13:DD X509v3 Authority Key Identifier: keyid:45:DC:F9:10:33:C0:45:28:EA:90:6E:83:73:06:6F:51:21:89:13:DD X509v3 Subject Alternative Name: URI:http://bblfish.net/people/henry/card#me Signature Algorithm: dsaWithSHA1 30:2c:02:14:78:69:1e:4f:7d:37:36:a5:8f:37:30:58:18:5a: f6:10:e9:13:a4:ec:02:14:03:93:42:3b:c0:d4:33:63:ae:2f: eb:8c:11:08:1c:aa:93:7d:71:01
  • 45.

Notas del editor

  1. Hello, my name is Henry Story. I work for Sun Microsystems where I research on the Semantic Web. I am tasked with finding ways to get people excited about what is happening in this space, which at first may seem very abstract. So I have been looking for problems that would affect people directly, have some real immediate business value, clearly demonstrate the power of the semantic web, and that is small enough that I don&apos;t need a big budget to get things done. After all I am in the business of convincing people. Once they are convinced I hope they will help out one way or another. Social Networking is big. It affects everyone in very personal ways. It is useful. It is what we are all about. Here I wish to show how one can build an secure, open, distributed global social network with no center of control. The only way to do this is using the semantic web....