1. Self-Managing Anycast Routing for DNS
NLnet Labs & SIDN Labs

2. Context

3. Providing High-Available & Reliable DNS Service
DNS service for important zones (globally)
reliable (trustworthy, security, …)
high-availability
reduce (average) latency
Examples
ccTLDs, gTLDs …
Common solution
distribute DNS name servers
anycast addressing and routing (BGP and IGP)

4. Uni-, Multi-, and Anycast

5. Local/Global Anycast Nodes
Local with IGP
RIPv2, OSPF, IS-IS, EIGRP
redundancy, load distribution, low latency within a network
Global with BGP
just BGP-4
redundancy, load distribution, low latency over global Internet

6. Research Question Very generic thesis Find optimal placement of nodes
distribution mechanism for flexible, adaptive deployment of DNS services (authoritative)
Find optimal placement of nodes
availability (also in relation with DDoS)
reliability (including security, integrity, trust)
low (average) latency
Alternative distribution mechanisms
p2p or some hybrid, e.g., zone files hosted at an ISP
anycast enhanced with self-management to support flexibility and adaptability

7. Project Plan

8. Plan & Approach
Solution should integrate/interoperate with current operational practices
Self-Managing Anycast Routing for DNS (SMARD)
BGP anycast: availability, reduce latency
self-*
configuration: flexibility, adaptability, …
optimization: load distribution, reduce latency, …
healing: recover from failures
protection: security, integrity, trust, …

9. Plan & Approach cont’d
Anycast & self-* to achieve mentioned goals, but …
Support for self-* loop
monitor, analyse, plan, execute
“Playground” to deploy anycast nodes at various/diverse topological locations
IaaS, …?

10. Architectural Overview

11. Self-*
Autonomic Computing

12. Autonomic Computing
“The Vision of Autonomic Computing,” Jeff Kephart and D. Chess, IEEE Computer, January
“...main obstacle to further progress in IT is a looming software complexity crisis.”
computer systems are becoming too massive, complex, to be managed even by the most skilled IT professionals
the workload and environment conditions tend to change very rapidly with time

13. Autonomic Computing cont’d
System that can manage themselves given high-level objectives
objectives can be expressed in term of service- level objectives or utility functions
Analogy human autonomic nervous system
“responsible for monitoring conditions in the internal environment and bringing about appropriate changes in them”
autonomic nervous system functions in an involuntary, reflexive manner

14. Centralized vs. Distributed Coordination
monitor
analyse
plan
execute
knowledge
monitor
analyse
plan
execute
knowledge
monitor
analyse
plan
execute
knowledge
monitor
analyse
plan
execute
knowledge

15. Example: Hierarchical Coordination (2 Layer)

16. Example cont’d Anycast nodes SMARD global M-A-P-E their own operation
monitor own behavior
local actions, global notification
SMARD global
M-A-P-E global operation
receive abstract/strategic monitor information
plan global actions for anycast nodes

17. DNS Anycast Considerations

18. Operation of Anycast Services, RFC 4786
Load distribution (not load balancing)
node placement
“catchment”
global/local anycast nodes …
Monitor availability changes according to location of client
signaling service availability
routing policies and topology changes
DNSMON and RIS/Route Views
Consistent service (trustworthy, availability, …)
data synchronization (consistent client response)
node autonomy & self-sufficiency (no cascading failure, but more complex management)
denial-of-service attack mitigation
service compromise
service hijacking

19. PERSPECTiVES

20. Results & Impact
Infrastructure for flexible, adaptive placement and management of DNS authoritative name servers
need a “playground” for placement and operational management
Infrastructure as a Service (IaaS)?
Full distributed vs. centralized coordination
bounded by need to be operational or practical deployable
operational costs vs. service and security
DDoS & spoofed traffic
DDoS mitigation
trace spoofed traffic to “real” source