1. Connections and Accesses for Hierarchical PCE
draft-chen-pce-h-connect-access-01
Huaimo Chen
Mehmet Toy
Lei Liu
Zhenqiang Li

2. Less Configuration and Simple Operation: Inter-AS Link
Inter-AS Link (no IGP running over it):
OSPF/ISIS-TE (RFC 5392/5316) for inter-AS links
1) Configure remote AS number
2) Configure remote router ID
E.g., P2P link between C and D
On C, configure D’s AS and ID
On D, configure C’s AS and ID
3) Configure IGP adjacency between PCE and IGP
4) PCE gets info after adjacency formed
BGP-LS (RFC 7752) for inter-AS links
Depends on IGP for some links
Configure BGP peer between PCE and BGP
PCE gets info after peer established
This draft:
Not need above configurations
Domain 2
B’s ID:
Domain 1
Domain 3
BAs ID:
C’s ID:
D’s ID:
E’s ID:
PCE
Run IGP
IGP Adj
No IGP Adj
Domain 2
B’s ID:
Domain 1
Domain 3
BAs ID:
C’s ID:
D’s ID:
E’s ID:
PCE
Run BGP
BGP Peer
No BGP Peer

3. New to BGP-LS, etc: ABR as connect + Access Points
Area Border Router (ABR)
Child PCEc
Child PCEa
Area 10
Domain c
Area 0
Child PCEb
Parent PCEp
ABR ID:
PCEp builds and maintains
domain topology using info on ABR from its child PCEs
PCEa as child sends its parent info on ABR
PCNtf (Updates)
ABR ID: , B=1
PCNtf (Updates)
ABR ID: , B=1
Router-ID TLV B=1
Access Point (Access for short): Address in domain accessible outside
Child PCEc
Child PCEa
Area 10
Domain c
Area 0
Child PCEb
Parent PCEp
Access:
Access:
Access points:
PCEa as child sends its parent info on Access
PCEp builds and maintains
access point table using info on Accesses from its child PCEs

4. New to BGP-LS, etc: Abstraction Procedures
Ways for child to abstract its domain to parent
Topology inside domain sent to parent
When child and parent in same service provider, child sends parent topology inside its domain and connections attached to domain
Border nodes full mess sent to parent (domain is abstracted as border nodes of domain fully messed, connected to adjacent domains)
Cloud connecting to adjacent domains sent to parent (domain is abstracted as a cloud, connected to adjacent domains)
Domain n
Domain n
Domain n
Domain n
Domain 2
Domain 1
Child PCEn
Child PCE1
Child PCE2
Parent PCEp
Child PCEc
Child PCEa
Domain a
Domain c
3. Cloud connecting to adjacent domains
Domain b
Child PCEb
1. Topology inside domain 1 to parent
2. BN full mess of domain n to parent
PCE2’s Domain
Domain a
Domain c
Domain b
Domain 2
PCE2 (child and as parent)
Sends its parent PCEp some Connections and Accesses. (Connections among its children’s domains are hidden, Connections to other domains are sent.)
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5. Summary Less Configuration and Simple Operation on Inter-AS Link
Presented
Less Configuration and Simple Operation on Inter-AS Link
New to BGP-LS, etc:
ABR as domain connection + Access Points
Abstractions of child’s domains to parent
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6. Next Step
Request for comments and suggestions

7. BGP-LS: LS Collection
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8. BGP-LS: Inter-AS Links
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9. BGP-LS: Related TLVs
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10. BGP-LS: Nodes and IP Reachability
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11. OSPF: Inter-AS Links
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12. FYI
[I-D.dhody-pce-applicability-actn] is an informational draft. In this draft, there is not any concrete procedure that describes how to summarize multiple domains under a child PCE/controller (also as a parent PCE/controller of other child PCEs/controllers) by this child PCE/controller into one domain to its parent PCE/controller.
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