Six/One Router Six/One Router A Scalable and Backwards-Compatible - PowerPoint PPT Presentation

Six/One Router Six/One Router A Scalable and Backwards-Compatible Solution for Provider-Independent Addressing 300 K number of number of r routing ta outing table entries ble entries 250 K 200 K 150 K 100 K Geoff Huston: CIDR Report 50 K www.cidr-report.org 1989 1992 1996 2000 2004 2008 Christian Vogt, Ericsson MobiArch workshop, Seattle, August 22, 2008

Towards More Scalable and Flexible Routing  core: flexible, but not scalable core  global routing table at every provider provider  track route changes Internet-wide provider provider  edge: scalable, but inflexible  provider-allocated addresses edge edge edge edge network network  renumbering on provider change network network edge edge  multi-homing infeasible network network host edge  need routing architecture that…  is scalable IP address 1234:5d:cff:fe22:57c1  avoids renumbering prefix = provider  supports multi-homing 1

Towards More Scalable and Flexible Routing  core: flexible, but not scalable core  global routing table at every provider provider  track route changes Internet-wide provider provider  edge: scalable, but inflexible  provider-allocated addresses edge edge edge edge network network  renumbering on provider change network network edge edge edge  multi-homing infeasible network network network host edge  need routing architecture that…  is scalable IP address IP address 1234:3ae:1b8:f5ff:fefd 1234:5d:cff:fe22:57c1  avoids renumbering prefix = provider prefix = provider  supports multi-homing 2

Towards More Scalable and Flexible Routing  core: flexible, but not scalable core  global routing table at every provider provider  track route changes Internet-wide provider provider  edge: scalable, but inflexible  provider-allocated addresses edge edge edge edge network network  renumbering on provider change network network edge edge edge edge  multi-homing infeasible network network network network host edge  need routing architecture that…  is scalable IP address IP address IP address 1234:5d:cff:fe22:57c1 1234:3ae:1b8:f5ff:fefd 1234:5d:cff:fe22:57c1  avoids renumbering 1234:3ae:1b8:f5ff:fefd prefix = provider prefix = provider  supports multi-homing prefix = provider 3

Address Indirection provider-allocated transit addresses in core provider provider forward reverse mapping mapping indirection router sending edge receiving edge provider- network network independent edge addresses  decouples addressing at edge from Internet core  global mapping system for remote edge addresses 4

Address Indirection provider-allocated transit addresses in core provider provider forward reverse mapping e e ➙ t t mapping indirection router sending edge receiving edge mapping provider- network network system independent edge addresses  decouples addressing at edge from Internet core  global mapping system for remote edge addresses 5

Address Indirection backwards legacy edge compatibility network provider-allocated transit addresses in core provider provider forward reverse mapping e e ➙ t t mapping indirection router sending edge receiving edge mapping provider- network network system independent edge addresses  decouples addressing at edge from Internet core  global mapping system for remote edge addresses 6

Address Indirection with Tunneling backwards proxy provider legacy edge compatibility network provider-allocated transit addresses in core provider provider decap encap e ➙ t e t indirection router sending edge receiving edge mapping provider- network network system independent edge addresses  increased bandwidth consumption  prolonged path  no incentives model for proxies 7

Contribution of Six/One Router address indirection enabling…  minimum extra packet overhead  direct-path routing  autonomous deployment idea: one-to-one address rewriting

Network Setup and Addressing provider-independent provider-allocated edge addresses transit addresses assigns owns edge provider network Six/One router host has rewrites edge address … and transit address  one-to-one mapping between edge/transit addresses 9

Address Rewriting edge provider provider edge network network correspondent host has edge address host has edge address rewrite reverse rewrite from from from to to to from from from to to to  provider-independence by rewriting local addresses  transparency through rewriting remote addresses 10

Backwards Compatibility edge provider network edge provider network correspondent host has edge address host has edge address rewrite from from no inverse rewrite to to from from to to  natural fall-back to unilateral rewriting  loss of transparency requires NAT traversal support 11

Multi-Homing Support correspondent host provider host edge provider network edge network provider has edge address host has edge addresses and 12

Multi-Homing Support correspondent host provider host edge provider network edge network provider has edge address from from extension ( ) from to to to from from from to to extension ( ) to  redirect via packet extension with original edge address 13

Conclusions address indirection enabling…  minimum extra packet overhead  direct-path routing  autonomous deployment’ …possible with one-to-one address rewriting  transparent with bilateral rewriting  backwards compatible with unilateral rewriting future work: implementation and experimentation