1. Routing and Addressing in Next-Generation EnteRprises (RANGER)
IETF 76 Routing Research Group
Fred L. Templin

2. RANGER Organizational Principles
Recursively-nested connected local network regions joined by Enterprise Border Routers (EBRs) – a network-of-networks
each distinct local network region is an “enterprise” unto itself
each enterprise is (a portion of) a local routing region that provides a “commons” for tunneling between EBRs
Routing scaling through separation of local addressing from global addressing
example enterprises:
Internet interdomain core
large academic campus network
corporate enterprise network
ISP networks
civil aviation networks
Mobile Ad-hoc Networks

3. Internet Protocol, Version 4 (IPv4) for local routing and addressing
Pouzin (1974) and Cerf (1977) proposed “CATENET Model for Internetworking” – network of networks
RANGER “concatenates” enterprises into a path with recursive re-encapsulation
Internet Protocol, Version 4 (IPv4) for local routing and addressing
Internet Protocol, Version 6 (IPv6) for global routing and addressing
Internet
A RANGER Path Constructed
using CATNET Principles
Routing scaling through spatial reuse of local addressing (RLOCs) with mapping system for global addresses (EIDs)
Global communications through recursive re-encapsulation across local routing regions (EIDs)
VET and SEAL
IPv4
IPv4
IPv4
IPv4
IPv4
IPv4
IPv6
IPv6

4. Virtual Enterprise Traversal (VET)
Concerns traversal of a single enterprise within the recursive nesting
“Version 2” of the Intra-Site Automatic Tunneling Addressing Protocol (ISATAP)
automatic tunneling over point-to-multipoint interfaces
IPv6 neighbor discovery over IPv6-in-IPv4 tunnels
EBR discovery to discover exit routers that can get you off the enterprise:
default routes through “default mappers” connected to provider networks
more-specific routes through EBRs connected to peer networks

5. VET Example < Default Mappers > IPv4 network IPv6 network

6. Mechanisms
Provider-aggregated EID addressing through PA prefix delegation (provider to customer)
Provider-independent EID addressing through PI prefix registration (customer to provider)
ICMP redirect from default mapper
Default mappers track PA/PI prefixes through a shared mapping system
Mapping system can be a local BGP instance, an enterprise naming service, etc.
Default mappers without a mapping forward the *their* default mappers
Default mappers in DFZ need full topology knowledge – Virtual Aggregation may help

7. Subnetwork Encapsulation and Adaptation Layer (SEAL)
tunneling adds encapsulation overhead that reduces the path MTU as seen by the original source
avoid path MTU discovery if possible due to unnecessary packet loss; black-holing due to ICMP filtering
have the tunnel do transparent link-layer adaptation
tunnel ingress discovers MRU of tunnel egress
end result is 1500 and larger gets through

8. SEAL Example < Default Mappers > IPv4 network IPv6 network

9. Civil Aviation Example
IPv6
IPv6
IPv6
Asian-Regional
ANSP
US-Regional
ANSP
European-Regional
ANSP
Global ATN Backbone
Routing and Addressing
Domain (IPv4)
ATC Workstation
Air Traffic Control
Functional Domain
Global Internet (IPv6)

10. “Traditional” Enterprise Example
Routing & Addressing in Next Generation EnteRprises (RANGER)
Network-of-networks architecture
Minimal touch-points (border routers only)
No changes to most hosts and routers
Fully-provisioned IP services; balanced blend of tunneling, translation and native
Gradual integration of IPv6
Customer-driven requirements lead policy and strategy
IPv6 and IPv4 in peaceful co-existence
It’s not an “either-or” decision
Tangible Benefits
Secure Mobile Architecture (SMA)
simplified management
logical partitioning
traffic engineering
end-to-end addressing
mobility and multihoming P
IPv4 Internet
IPv6 Internet
Enterprise Network
Fully Provisioned IP Services
Enterprise Network
Advanced IPv6 Deployment
Enterprise Network
Initial IPv6 Deployment
Enterprise Network
IPv4-Only

11. Intra-Site Automatic Tunnel Addressing Protocol (ISATAP)
Virtual Enterprise Traversal (VET)
Subnetwork Encapsulation and Adaptation Layer (SEAL)
Routing and Addressing in Next-Generation EnteRprises (RANGER)
RANGER Scenarios