HAIR: Hierarchical Architecture for Internet Routing Re-Architecting - - PowerPoint PPT Presentation

HAIR: Hierarchical Architecture for Internet Routing

Re-Architecting the Internet – ReArch ’09 Wolfgang Mühlbauer

ETH Zürich / TU Berlin wolfgang.muehlbauer@tik.ee.ethz.ch

Anja Feldmann Luca Cittadini Randy Bush Olaf Maennel

Deutsche Telekom Università Internet Initiative Loughborough Labs / TU Berlin Roma Tre Japan University

ReArch ’09 — Rome, Italy — December 1st, 2009 HAIR: Hierarchical Architecture for Internet Routing 1

Re-Architecting Internet Routing

Routing problems:

routing table growth high update rates address shortage mobility multi-homing traffic engineering lack of security ...

50000 100000 150000 200000 250000 300000 2001 2002 2003 2004 2005 2006 2007 2008 active BGP entries years

Clean-slate approach: assume we could start from scratch

ideas may be incrementally applicable to current Internet

Our work:

Hierarchical Architecture for Internet Routing (HAIR)

ReArch ’09 — Rome, Italy — December 1st, 2009 HAIR: Hierarchical Architecture for Internet Routing 2

Outline

1

Related Work

2

Architecture

3

Evaluation

4

Conclusion

ReArch ’09 — Rome, Italy — December 1st, 2009 HAIR: Hierarchical Architecture for Internet Routing 3

Outline

1

Related Work

2

Architecture

3

Evaluation

4

Conclusion

ReArch ’09 — Rome, Italy — December 1st, 2009 HAIR: Hierarchical Architecture for Internet Routing 4

Related Work

LISP

addressing: separate

locators (RLOC) identifiers (EID)

packet forwarding:

map EID to RLOC tunnel packet through core based on RLOC

multihoming easier routing table size ↓

CORE EDGE

EID 1 RLOC 1/RLOC 2 EID 2 RLOC 3 Tunnel router RLOC 2 Tunnel router RLOC 3

tunnel

Tunnel router RLOC 1

shim6

multihoming for IPv6-enabled sites hosts control which locator is used

HLP , HIT, and many others

ReArch ’09 — Rome, Italy — December 1st, 2009 HAIR: Hierarchical Architecture for Internet Routing 5

Clean-Slate: Design Choices

Separation of locators/identifiers (LOC/ID split)?

no: current Internet yes: LISP

Flat/structured namespaces for LOCs and IDs?

flat: Routing On Flat Labels (ROFL), SIGCOMM’06 structured: current Internet

Host- or network-based solution?

host-based: Shim6, no state in the network network-based: LISP , mapping done at tunnling router

...

ReArch ’09 — Rome, Italy — December 1st, 2009 HAIR: Hierarchical Architecture for Internet Routing 6

Outline

1

Related Work

2

Architecture

3

Evaluation

4

Conclusion

ReArch ’09 — Rome, Italy — December 1st, 2009 HAIR: Hierarchical Architecture for Internet Routing 7

HAIR: Key Ideas

1

Separation of locator/identifier function of IP address

2

Use of hierarchical routing and mapping system

3

Edge-based: if possible transfer tasks to edge hosts, keep network simple

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HAIR: Hierarchical Routing

Why hierarchical?

to provide scalability → graph theory

Leverage Internet hierarchy e.g., 3 levels:

core: large transit provider intermediate: small providers edge: access networks, LAN

ReArch ’09 — Rome, Italy — December 1st, 2009 HAIR: Hierarchical Architecture for Internet Routing 9

HAIR: Packet Forwarding

Locator: 3 parts

core exit point intermediate exit point identifier (ID)

Forwarding:

1

send packet to core (direct peerings supported)

2

forward along “exit points”

Local routing scope within hierarchy levels

ReArch ’09 — Rome, Italy — December 1st, 2009 HAIR: Hierarchical Architecture for Internet Routing 10

HAIR: Hierarchical Mapping System

Design requirements

scale with number of hosts fast response times

Hierarchical directories:

local: intermediates global: core

Resolve mapping

1

get pointer to local directory

2

get actual mappings

Edge-based:

request sent by end host no action needed from e.g., core exit points

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Dynamics

Link/router failure inside core or intermediate:

find alternative route between all pairs of exit points updates are localized in scope to core or intermediate

Failing or unreachable exit point:

e.g., monitor reachability of exit points update all affected locators in the mapping system

Change of locator:

“intra-domain”: update local directory “inter-domain”: update global directory, move locators

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Outline

1

Related Work

2

Architecture

3

Evaluation

4

Conclusion

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Estimating the Benefits

Goal: benefits if HAIR was deployed in today’s Internet?

how much can we scale the DFZ routing table? core isolated from update churn originated by “edge”?

Data sources

BGP updates and table dumps classification of ASs according to business type e.g., transit provider, enterprise networks → Dhamdhere et al., IMC 2008

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Estimating the Benefits – Results

DFZ table size: reduction by more than a half Updates: majority of current updates from “edge”, see plot

✛ ✛ EDGE EDGE

Scalability since Internet mainly grows at the “edge”

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Proof-of-Concept Implementation

Requirements:

support existing applications standard IP forwarding user space bootstrapping

Use existing software

IPv6 Click Scapy

Setup in testbed

latency: ping throughput iperf mobility scenarios

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Discussion/Summary

Scalability

routing AND mapping largely on a local scope HAIR captures growth of Internet at the edge

Multihoming, multipath, inbound traffic engineering:

can be supported by mapping system

Migration path

support legacy hosts via NAT-like boxes

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Outline

1

Related Work

2

Architecture

3

Evaluation

4

Conclusion

ReArch ’09 — Rome, Italy — December 1st, 2009 HAIR: Hierarchical Architecture for Internet Routing 18

Conclusion

Key ideas:

separation of locator/identifier function of IP address use of hierarchical routing and mapping system edge-based: if possible transfer tasks to edge hosts, keep network simple

Current status:

architecture specified proof-of-concept implementation demonstrates feasibility

Future work:

mapping system security model and analysis

ReArch ’09 — Rome, Italy — December 1st, 2009 HAIR: Hierarchical Architecture for Internet Routing 19

Thank you!

ReArch ’09 — Rome, Italy — December 1st, 2009 HAIR: Hierarchical Architecture for Internet Routing 20

Conclusion

Key ideas:

separation of locator/identifier function of IP address use of hierarchical routing and mapping system edge-based: if possible transfer control to edge hosts, keep network simple

Current status:

architecture specified proof-of-concept implementation demonstrates feasibility

Future work:

mapping system security model and analysis

ReArch ’09 — Rome, Italy — December 1st, 2009 HAIR: Hierarchical Architecture for Internet Routing 21