190 likes | 271 Views
SCION: S calability, C ontrol and I solation O n Next-Generation N etworks. Xin Zhang, Hsu-Chun Hsiao, Geoff Hasker, Haowen Chan, Adrian Perrig, David Andersen. The Internet is still un reliable and in secure!. Feb 2008: Pakistani ISP hijacks YouTube prefix. S-BGP origin attest.
E N D
SCION:Scalability, Control and Isolation On Next-Generation Networks Xin Zhang, Hsu-Chun Hsiao, Geoff Hasker, Haowen Chan, Adrian Perrig, David Andersen
The Internet is still unreliable and insecure! Feb 2008: Pakistani ISP hijacks YouTube prefix S-BGP origin attest. Apr 2010: A Chinese ISP inserts fake routes affecting thousands of US networks. Application S-BGP route attest. Transport Nov 2010: 10% of Internet traffic 'hijacked' to Chinese servers due to DNS Tampering. Multi-path Network DNSSec Data link • Fixes to date – ad hoc, patches • Inconvenient truths • S-BGP: delayed convergence • Global PKI: single root of trust Physical
Limitations of the Current Internet • Too little or too much path control by end points • Destination has too little control over inbound paths • Source has too much control to aggregate DDoS traffic A Prefer the red path … B M C D’s prefix here! D
Limitations of the Current Internet • Too little or too much path control by end points • Destination has too little control over inbound paths • Source has too much control to aggregate DDoS traffic • Lack of routing isolation • A failure/attack can have global effects • Global visibility of paths is not scalable • Lack of route freshness • Current (S-)BGP enables replaying of obsolete paths
Related Work • Routing security • S-BGP, soBGP, psBGP, SPV, PGBGP • Routing control • Multipath (MIRO, Deflection, Path splicing, Pathlet), NIRA • Scalable and policy-based routing • HLP, HAIR, RBF • Secure DNS • DNSSec • Source accountability and router accountability • AIP, Statistical FL, PAAI
Wish List (1): Isolation • Localization of attacks … … • Mutually distrusting domains, no single root of trust Independent routing region … … … … … … … M Attacks(e.g., bad routes)
Wish List (2): Balanced Control • Source, destination, transit ISPs all have path control • Support rich policies and DDoS defenses … … … … I2 L3 … … A B C Hide the peering link from CMU PSC D CMU 7
Wish List (3): Explicit Trust • Know who needs to be trusted • Enforceable accountability … … … … … … X Y Z Internet Level 3 I2 PSC Who will forward Packets on the path? Go through X and Z, but not Y CMU
SCION Architecture Overview path srv S: blue paths D: red paths • Trust domain (TD)s • Isolation and scalability TD TD Core • Path construction • scalability • Path resolution • Control • Explicit trust PCB PCB PCB PCB AD: admin domain • Route joining (shortcuts) • Efficiency, flexibility Destination Source
Logical Decomposition • Split the network into a set of trust domains (TD) TD: isolation of route computation TD cores: interconnected Tier-1 ADs (ISPs) core core Down-paths Up-paths Destination Source
Path Construction Beacons (PCBs) : signature : interface : Opaque field : expiration time = SIG( || || ) TD Core = ||MAC( ) A PCB PCB PCB PCB = || MAC( || ) = SIG( || || || ) B = || MAC( || ) = SIG( || || || ) C Embed into pkts
Performance Benefits • Scalability • Routing updates are scoped within the local TD • Flexibility • Transit ISPs can embed local routing policies in opaque fields • Simplicity and efficiency • No inter-domain forwarding table
Evaluation Methodology • Use of CAIDA topology information • Assume 5 TDs (AfriNIC, ARIN, APNIC, LACNIC, RIPE) • We compare to S-BGP/BGP
Performance Evaluation • Additional path length (AD hops) compared to BGP • without shortcuts: 21% longer • with shortcuts: • 1 down/up- path: 6.7% • 2 down/up- path: 3.5% • 5 down/up- path: 2.5%
Policy Expressiveness Evaluation • Fraction of BGP paths available under SCION, reflecting SCION’s expressiveness of BGP policies
Security Evaluation • Resilience against routing and data-plane attacks • Malicious ADs announce bogus links between each other • S-BGP • SCION
Conclusions • Basic architecture design for a next-generation network that emphasizes isolation, control and explicit trust • Highly efficient, scalable, available architecture • Enables numerous additional security mechanisms, e.g., network capabilities Application Transport Network Data link Physical
Questions? Xin Zhang <xzhang1@cmu.edu>