Source-Address-Dependent Routing and Source Address Selection for IPv6 Hosts: Overview of the Problem Space
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paper_title: Ingress Filtering for Multihomed Networks

paper_content:

BCP 38, RFC 2827, is designed to limit the impact of distributed denial of service attacks, by denying traffic with spoofed addresses access to the network, and to help ensure that traffic is traceable to its correct source network. As a side effect of protecting the Internet against such attacks, the network implementing the solution also protects itself from this and other attacks, such as spoofed management access to networking equipment. There are cases when this may create problems, e.g., with multihoming. This document describes the current ingress filtering operational mechanisms, examines generic issues related to ingress filtering, and delves into the effects on multihoming in particular. This memo updates RFC 2827.
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paper_title: OSPF for IPv6

paper_content:

This document describes the modifications to OSPF to support version 6 of the Internet Protocol (IPv6). The fundamental mechanisms of OSPF (flooding, DR election, area support, SPF calculations, etc.) remain unchanged. However, some changes have been necessary, either due to changes in protocol semantics between IPv4 and IPv6, or simply to handle the increased address size of IPv6.
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paper_title: IPv6 Multihoming without Network Address Translation

paper_content:

Network Address and Port Translation (NAPT) works well for conserving ::: global addresses and addressing multihoming requirements because an ::: IPv4 NAPT router implements three functions: source address selection, ::: next-hop resolution, and (optionally) DNS resolution. For IPv6 hosts, ::: one approach could be the use of IPv6-to-IPv6 Network Prefix ::: Translation (NPTv6). However, NAT and NPTv6 should be avoided, if at ::: all possible, to permit transparent end-to-end connectivity. In this ::: document, we analyze the use cases of multihoming. We also describe ::: functional requirements and possible solutions for multihoming without ::: the use of NAT in IPv6 for hosts and small IPv6 networks that would ::: otherwise be unable to meet minimum IPv6-allocation criteria. We ::: conclude that DHCPv6-based solutions are suitable to solve the ::: multihoming issues described in this document, but NPTv6 may be ::: required as an intermediate solution.
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paper_title: Distributing Address Selection Policy Using DHCPv6

paper_content:

RFC 6724 defines default address selection mechanisms for IPv6 that ::: allow nodes to select an appropriate address when faced with multiple ::: source and/or destination addresses to choose between. RFC 6724 allows ::: for the future definition of methods to administratively configure the ::: address selection policy information. This document defines a new ::: DHCPv6 option for such configuration, allowing a site administrator to ::: distribute address selection policy overriding the default address ::: selection parameters and policy table, and thus allowing the ::: administrator to control the address selection behavior of nodes in ::: their site.
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Title: Source-Address-Dependent Routing and Source Address Selection for IPv6 Hosts: Overview of the Problem Space

Section 1: Introduction
Description 1: This section provides an introduction to the paper, explaining the overall context and importance of source-address-dependent routing (SADR) and the issues that arise due to ingress filtering, especially in multihomed networks.

Section 2: Scope
Description 2: This section outlines the scenarios where source address dependent routing is necessary from the host's perspective, elaborating on different configurations and setups, including multi-prefix multi-interface scenarios and corporate VPNs.

Section 3: Scenario 2: Multi-Prefix Multihoming
Description 3: This section delves into the specific multi-prefix multihoming use case, explaining the challenges and the need for source address dependent routing to prevent packet drops due to ingress filtering in various networking environments, including home networks.

Section 4: Analysis of Source Address Dependent Routing
Description 4: This section presents an analysis of the previously discussed scenarios, examining the relevance and application of SADR in different provisioning domains and how proper configuration can mitigate issues.

Section 5: Scenarios Analysis
Description 5: This section analyzes the scenarios detailed earlier, discussing potential solutions and configurations to avoid ingress filtering and maintain proper routing.

Section 6: Discussion on Alternate Solutions
Description 6: This section provides a discussion on alternative solutions to SADR, including source address selection rules and the necessary information that hosts need for correct source address selection without making specific recommendations.

Section 7: Router Advertisement Option
Description 7: This section discusses the need for new router advertisement options for source address dependent routing, including route prefix with source address/prefix option and the configuration requirements for both router advertisement and DHCP options.