Routing Architecture for the Next Generation Internet (RANGI)

Transcription

1 Routing Architecture for the Next Generation Internet (RANGI) SNU, MMLAB Taewan You

2 Contents Introduction RANGI overview Host ID Locator Resolution Features MH, TE Discussion RFC 6115 Conclusion 2

3 Background RANGI was presented twice to RRG 73 rd IETF, Minneapolis, November 21, 2008 Internet 3.0 and RANGI Based on paper: Hierarchical Routing Architecture, Proc. 4th Euro-NGI Conference, Poland, April th IETF, Hiroshima, November 8, 2009 Based on IETF draft: draft-xu-rangi-01.txt Latest release draft-xu-rangi-04.txt draft-xu-rangi-proxy-01.txt 3

4 Design and Goal ID/locator split p Mobility and Multi-homing p Routing Scalability p IPv4/IPv6 Coexistence and Transition p Transition Mechanism for RANGI Deployable New Internet Architecture Hierarchical Management p Reasonable Business Model p Clear Trust Boundary p Business-friendly p Cryptographic Host Identifier Security 4

5 Introduction RANGI is similar with HIP Transport Network Data Link IP Transport Flat Host ID (128bit) Locator (128bit) Data Link HIP Transport Hierarchical Host ID (128bit) IPv4-embeded IPv6 Address (128bit) Data Link RANGI RANGI Hierarchical and cryptographic Host Identifier (ID) Special IPv4-embeded IPv6 address (Locator) Deployability Site-controlled traffic-engineering, simplified renumbering 5

6 RANGI Overview Get ID and Locator of Dest host Transport Host ID 1 Transport Host ID ID/Locator Mapping System Mapping DNS DNS SystemDHT DNS RM Transport IPv6 Locator IPv6 Locator Transport Host ID IPv6 Locator IPv4 Layer 2 BR1 3 BR2 LD #2 4 BR3 5 BR4 BR4 Host ID IPv6 Locator IPv4 Layer LD #3 LD 4#3 6 Tunneled by IPv6 over IPv4 Packets forwarded based on Dest LDID Packets tunneled based on local locator 6

7 HOST ID n bits (n=64) 128-n bits AD ID Local Host ID Country ID Authority ID Region ID (example) AD(Administrative Domain)ID Organizational semantics and trust boundaries. Reasonable business model for the ID to locator mapping system. Local Host ID The hash over the AD ID and the public key of the host. Secure the ID ownership. Use CGA (RFC3972) as host ID in our implementation for simplicity 7

8 LOCATOR 96 bits 32 bits LD ID LL(IPv4) LD(Locator Domain)ID Globally identify each LD (e.g., site network). LDID is actually PA (Provider Assigned) /96 IPv6 prefix. LL (Local Locator) Each LD uses independent IPv4 address space (e.g., private address). When ISP changed, only LDID changes, local locator unchanged. GL (Global Locator)= LDID + LL Use ISATAP (RFC5214) address as GL in our implementation for simplicity 8

9 ID to Locator Resolution Country 1 Root Country 2 Country n Routing ba sed on the AD ID City 1 City 2 City 3 City n DHT DHT Hierarchical DHT based Mapping System Reasonable business model and clear trust boundary. Use reverse-dns as mapping system in our current implementation for simplicity DHT DHT Routing ba sed on the local host I D (i.e. Hash value) 9

10 Routing & Forwarding Payload HI(A)->HI(B) IPv6(A)->IPv6(B) IPv4(A) ->IPv4(BR1) Payload HI(A)->HI(B) IPv6(A)->IPv6(B) IPv4(BR2) -> IPv4(BR3) Payload HI(A)->HI(B) IPv6(A)->IPv6(B) IPv4(BR4) -> IPv4(B) Host A Host B LD #1 (Pub/Pri IPv4) LDBR1 BR2(AFBR) IPv4 Internet BR3(AFBR) LDBR4 LD #3 (Pub/Pri IPv4) Use ISATAP like mechanism in site (edge) networks Use Softwire mechanism in provider ASes Either intra-as softwire [RFC5565] or inter-as softwire (draft-xu-softwire-tunnel-endpoint) mechanism works well. 10

11 Site Multi-homing LDID_1+LL(A)->GL(B) LDID_1+LL(A)->GL(B) LDID_1+LL(A)->GL(B) LDID_1+LL(A)->GL(B) BR2 ISP #1 Host A LD #1 BR1 Host B LDID_1 assigned by ISP #1 LDID_2 assigned by ISP #2 Source LD ID bas ed policy routing BR3 ISP #2 Multiple PA LDIDs are allocated to a multi-homed si te network Routing system scales well due to the usage of multiple PA locators. 11

12 Site-controlled Traffic-Engineering LDID_1+LL(A)->GL(B) BR1 rewrites the sourc e LDID before performi ng source-based policy routing BR2 ISP #1 Host A LD #1 BR1 Host B LDID_1 assigned by ISP #1 LDID_2 assigned by ISP #2 BR3 LDID_2+LL(A)->GL(B) ISP #2 LDID_2+LL(A)->GL(B) LDID_2+LL(A)->GL(B) Site LDBR rewrites source LDIDs of the outgoing pa ckets before performing source-based policy routin g. Borrow ideas from GSE, Six/One. 12

13 Site-controlled Traffic-Engineering BR2 ISP #1 Host A LD #1 BR1 Host B GL(B) -> LDID_2+LL(A) LDID_1 分配自 ISP #1 LDID_2 分配自 ISP #2 BR3 GL(B) -> LDID_2+LL(A) ISP #2 GL(B) -> LDID_2+LL(A) GL(B) -> LDID_2+LL(A) Return packets follow the same path as the outgoing packets travel along. 13

14 RFG 6115-GAIN Routing Scalability Solved by keeping separate local and global locators Provider assigned locator domain ID Traffic Engineering border routers select locator & path Mobility and Multi-homing Identifier locator split Session portability / continuity Simplified Renumbering Local IPv4 addresses do not change Global ID does not change 14

15 GAIN Decoupling Location and Identification Routing Quality Allows BRs to select the paths with shorter delay or better performance Size of global routing table and update frequency reduced significantly Routing Security RM enforce policies including security Local addresses and paths are not disclosed outside Incremental Deployability Allow step by step deployment and long-term evolution 15

16 COST RANGI Costs A host change is required The first-hop LDBR change is required to support site-controlled traffic-engineering capability. The ID->locator mapping system is a new infrastructure to be deployed. RANGI proxy needs to be deployed for communication between RANGI aware hosts and legacy hosts. 16

17 CRITIQUE Hierarchy is overload To make ID unique, to drive lookup, etc. Strong identification at the cost of crypto Doesn t require receiver to validate No explicit solution for mobility race condition No mention of home-agent-like device (?) RANGI uses proxies to deal with legacy IPv4 and IPv6 sites 17

18 적용 Deployability Add Proxy mechanism Interact with IPv6 network 18

19 Conclusion-RANGI ID/Locator split Mobility Hierarchical ID Administrative Scalability Cryptographic ID Security (like HIP) 128-bit ID IPv6 Addresses (like CGA) Easy Application Transition Local IPv4 embedded in IPv6 Simplify renumbering (like ISATAP) IPv6 tunnel over IPv4 (ISATAP tunnel) Easy transition (allow IPv4 intra-domain routers) Address overwriting at border routing (Six/One or GSE) Traffic engineering Policy control (during ID to locator translation) 19