Network Support for Sharing

2 CABO: Concurrent Architectures are Better than One No single set of protocols or functions –Different applications with different needs –Multiple parties offering end-to-end services Instead, multiple networks in parallel –Virtual networks on a common substrate –Customization of the network functions

3 Separate Infrastructure from Service Infrastructure: physical infrastructure needed to build networks Service: slices of physical infrastructure from one or more providers The same entity may sometimes play these two roles.

4 CABO as a New Architecture Virtualization –Multiple logical routers on shared hardware –Resource isolation in CPU, FIBs, and bandwidth Programmability –General-purpose CPUs for control & manipulation –Network processors & FPGAs for fast forwarding Economic refactoring –Infrastructure provider: manage routers and links –Service provider: offer end-to-end services

5 VINI/Trellis Deployment Platform Lightweight containers on a single OS Each virtual host sees virtual Ethernet links Packet forwarding and traffic shaping remain outside of the container

Network Support for Accountability

7 Internet Accountability Mechanisms to identify, isolate, punish bad behavior Distinct from accounting (cf. original Clark design goals) What is it? Why might the network need to support it? Attacks on the routing system Control over traffic Tracking and mitigating malice –Spam –Botnets –Phishing

8 Facets of Internet Accountability Source: defense against address forgery Data-plane: identify faulty network elements Control-plane: identify forged routing messages Recourse to avoid faulty or malicious elements –Scalable network support for path diversity –Better mechanisms to curtail unwanted traffic

9 AIP: Accountable IP Refactoring of Internet addresses: AD:EID –AD: The autonomous domain of the host –EID: A globally unique endpoint identifier Addresses are self-certifying Why change addressing? –Forms the cornerstone of routing, forwarding, identity –Current address structure makes existing mechanisms clumsy –New structure retains simplicity at the network layer and above ADEID Hash of autonomous domains public key Globally valid endpoint identifier (cf. IPv6 CGA, HIP, etc.)

10 Source Accountability Problem: Sources can forge IP addresses –Can complete three-way handshakes (LAN spoofing) Why it matters: Complicates filtering, blacklisting. –Spam campaigns regularly have 70% fresh IP addresses Solution: Self-certification + Challenge/Response

11 Control-Plane Accountability Problem: Routing messages can be forged Why it matters: –Misconfiguration: AS 7007, ConEdison route leak –Malice: Spammers stealing address space Solution: S-BGP-style attestations + self-cert –Interdomain routing and forwarding is on Ads –The AD is the public key and the address –Eliminates the need for a mapping between IP address space and organizations

12 Data-Plane Accountability Problem: Network elements drop packets, fail, and otherwise give rise to poor performance One Solution: In-Band Path Diagnosis Routers keep track of number of packets seen per flow Each router stamps each packet with current flow counter value If current counter value does not equal routers expected packet count for that flow, router marks packet IP Header New Shim Header Transport header Method Overview