Biblio
Mobility and multihoming have become the norm in Internet access, e.g. smartphones with Wi-Fi and LTE, and connected vehicles with LTE and DSRC links that change rapidly. Mobility creates challenges for active session continuity when provider-aggregatable locators are used, while multihoming brings opportunities for improving resiliency and allocative efficiency. This paper proposes a novel migration protocol, in the context of the eXpressive Internet Architecture (XIA), the XIA Migration Protocol. We compare it with Mobile IPv6, with respect to handoff latency and overhead, flow migration support, and defense against spoofing and replay of protocol messages. Handoff latencies of the XIA Migration Protocol and Mobile IPv6 Enhanced Route Optimization are comparable and neither protocol opens up avenues for spoofing or replay attacks. However, XIA requires no mobility anchor point to support client mobility while Mobile IPv6 always depends on a home agent. We show that XIA has significant advantage over IPv6 for multihomed hosts and networks in terms of resiliency, scalability, load balancing and allocative efficiency. IPv6 multihoming solutions either forgo scalability (BGP-based) or sacrifice resiliency (NAT-based), while XIA's fallback-based multihoming provides fault tolerance without a heavy-weight protocol. XIA also allows fine-grained incoming load-balancing and QoS-matching by supporting flow migration. Flow migration is not possible using Mobile IPv6 when a single IPv6 address is associated with multiple flows. From a protocol design and architectural perspective, the key enablers of these benefits are flow-level migration, XIA's DAG-based locators and self-certifying identifiers.
With the growing number of proposed clean-slate redesigns of the Internet, the need for a medium that enables all stakeholders to participate in the realization, evaluation, and selection of these designs is increasing. We believe that the missing catalyst is a meta network architecture that welcomes most, if not all, clean-state designs on a level playing field, lowers deployment barriers, and leaves the final evaluation to the broader community. This paper presents Linux XIA, a native implementation of XIA in the Linux kernel, as a candidate. We first describe Linux XIA in terms of its architectural realizations and algorithmic contributions. We then demonstrate how to port several distinct and unrelated network architectures onto Linux XIA. Finally, we provide a hybrid evaluation of Linux XIA at three levels of abstraction in terms of its ability to: evolve and foster interoperation of new architectures, embed disparate architectures inside the implementation's framework, and maintain a comparable forwarding performance to that of the legacy TCP/IP implementation. Given this evaluation, we substantiate a previously unsupported claim of XIA: that it readily supports and enables network evolution, collaboration, and interoperability - traits we view as central to the success of any future Internet architecture.