This paper presents the design of a new Internet routing architecture (NIRA). In today’s Internet, users can pick their own ISPs, but once the packets have entered the network, the users have no control over the overall routes their packets take. NIRA aims at providing end users the ability to choose the sequence of Internet service providers a packet traverses. User choice fosters competition, which imposes an economic discipline on the market, and fosters innovation and the introduction of new services. This paper explores various technical problems that would have to be solved to give users the ability to choose: how a user discovers routes and whether the dynamic conditions of the routes satisfy his requirements, how to efficiently represent routes, and how to properly compensate providers if a user chooses to use them. In particular, NIRA utilizes a hierarchical provider-rooted addressing scheme so that a common type of domainlevel route can be efficiently represented by a pair of addresses. In NIRA, each user keeps track of the topology information on domains that provide transit service for him. A source retrieves the topology information of the destination on demand and combines this information with his own to discover end-to-end routes. This route discovery process ensures that each user does not need to know the complete topology of the Internet.

For performance or cost reasons, Autonomous Systems (AS) often need to control the flow of their incoming interdomain traffic. Controlling its incoming traffic is a difficult task since it often implies influencing ASes on the path. The current BGP-based techniques that an AS can use for this purpose are primitive. Moreover, their effect is often difficult to predict.

Multihoming, the practice of connecting to multiple providers, is becoming highly popular. Due to the growth of the BGP routing tables in the Internet, IPv6 multihoming is required to preserve the scalability of the interdomain routing system. A proposed method is to assign multiple provider-dependent aggregatable (PA) IPv6 prefixes to each site, instead of a single provider-independent (PI) prefix. We show that the use of multiple PA prefixes not only allows route aggregation but also can be used to reduce end-to-end delays by leveraging the Internet path diversity. We quantify the gain in path diversity, and show that a dualhomed stub AS that uses multiple PA prefixes has already a better Internet path diversity than any multihomed stub AS that uses a single PI prefix, whatever its number of providers. The benefits provided by the use of IPv6 multihoming with multiple PA prefixes are an opportunity to develop the support for quality of service and traffic engineering.

IPv6 multihoming with multiple prefixes increases the number of paths available between multihomed sites. Selecting the path with the lowest delay is important for many interactive and real-time applications. We propose

Site multihoming is a method by which an Internet end-site, for example an enterprise network, may connect to multiple service providers simultaneously. There are many reasons why multihoming is desirable, e.g. service resilience, network load balancing or provider independence. In the IPv4 Internet, multihoming has been achieved by use of relatively simple techniques, including networks advertising their network prefixes -- whether such prefixes are independent of the Internet Service Providers (ISPs) or not -- to the Internet global routing infrastructure. With the introduction of IPv6 the vast increase in the number of potential site prefixes means that for scalable site multihoming we cannot repeat such IPv4 multihoming practices. Thus new IPv6 multihoming solutions are required. In this paper we present an overview of currently proposed solutions and explore the challenges and motivations of site multihoming. Such a review is timely because multihoming remains the main perceived obstacle to widespread IPv6 deployment in mission-critical environments.

Very recent activities in the IETF and in the Routing Research Group (RRG) of the IRTG focus on defining a new Internet architecture, in order to solve scalability issues related to interdomain routing. The approach that is being explored is based on the separation of the end-systems ’ addressing space (the identifiers) and the routing locators ’ space. This separation is meant to alleviate the routing burden of the Default Free Zone, but it implies the need of distributing and storing mappings between identifiers and locators on caches placed on routers. In this paper we evaluate the cost of maintaining these caches when the distribution mechanism is based on a pull model. Taking as a reference the LISP protocol, we base our evaluation on real Netflow traces collected on the border router of our campus network. We thoroughly analyze the impact of the locator/ID separation, and related cost, showing that there is a trade-off between the dynamism of the mapping distribution protocol, the demand in terms of bandwidth, and the size of the caches. Categories and Subject Descriptors