Guarantees for traffic traversing the public Internet are hard to come by, as service-level agreements are typically only available for traffic within a single autonomous system or towards direct neighbors. This deficiency leads to unpredictable performance already under normal conditions and can cause outages in the face of networklevel distributed-denial-of-service (DDoS) attacks. In this paper, we present an architecture achieving guaranteed bandwidth properties for global inter-domain network traffic. The control plane of our architecture is based on a distributed server infrastructure, while the data plane enables efficient packet forwarding on per-flow stateless routers. Our implementation demonstrates the technical feasibility and scalability of the design.

Path aware networking (PAN) is a promising approach that enables endpoints to participate in end-to-end path selection. PAN unlocks numerous benefits, such as fast failover after link failures, application-based path selection and optimization, and native interdomain multi-path. The utility of PAN hinges on the availability of a large number of high-quality path options. In an inter-domain context, two core questions arise. Can we deploy such an architecture natively in today's Internet infrastructure without creating an overlay relying on BGP? Can we build a scalable multi-path routing system that provides a large number of high-quality paths?

Denial-of-service attacks have become increasingly prevalent in the Internet. In many cases they are enabled or facilitated by the lack of source authentication?it is often easy for an attacker to spoof its own IP address and thus launch reflection attacks or evade detection. There have been attempts in the past to resolve this issue through filtering or cryptography-based techniques; however, there is still no sufficiently strong system in place today-all proposals either provide weak security guarantees, are not efficient enough, or lack incentives for deployment. In this paper we present PISKES, a pragmatic Internet-scale key-establishment system enabling firstpacket authentication. Through the PISKES infrastructure, any host can locally obtain a symmetric key to enable a remote service to perform source-address authentication. The remote service can itself locally derive the same key with efficient cryptographic operations. PISKES thus enables packet authentication for a wide variety of systems including high-throughput applications like DNS. We have implemented a prototype system that enables a DNS server to verify the source of every received packet within 85 ns, which is over 220 times faster than a system based on asymmetric cryptography. PISKES has been developed for the SCION secure Internet architecture but is also applicable to today's Internet. With its strong source-authentication properties and highly efficient operation it has the potential to finally bring network-layer authentication to the Internet