Abstract-We review the main challenges and survey promising techniques for network interconnection in the Internet of the future. To this end, we first discuss the shortcomings of the Internet's current model. Among them, many are consequence of unforeseen demands on the original Internet design such as: mobility, multihoming, multipath, and network scalability. These challenges have attracted significant research efforts in the latest years because of both their relevance and complexity. In this survey, for the sake of completeness, we cover several new protocols for network interconnection spanning both incremental deployments (evolutionary approach) and radical proposals to redesign the Internet from scratch (clean-slate approach). We focus on specific proposals for future internetworking such as: Loc/ID split, flat routing, network mobility, multipath and content-based routing, path programmability, and Internet scalability. Although there is no consensus on the future internetworking approach, requirements such as security, scalability, and incremental deployment are often considered.