IPv6 CE Routers LAN Prefix Delegation

Status of This Memo

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Table of Contents

2. Requirements Language

The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all capitals, as shown here.¶

This document also makes use of internal conceptual variables to describe protocol behavior and external variables that an implementation must allow system administrators to change. The specific variable names, how their values change, and how their settings influence protocol behavior are provided to demonstrate protocol behavior. An implementation is not required to have them in the exact form described here, as long as its external behavior is consistent with that described in this document.¶

3. Terminology

The following terminology is defined for this document.¶

• IPv6 CE Router: A router intended for home or small-office use that forwards packets not explicitly addressed to itself as defined in [RFC7084].¶
• Internet Service Provider (ISP): An entity that provides access to the Internet. In this document, a service provider specifically offers Internet access using IPv6, and may also offer IPv4 Internet access. The service provider can provide such access over a variety of different transport methods such as DSL, cable, wireless, and others.¶

4. Architecture

                     +-----------+
                     |  Service  |
                     |  Provider |
                     |   Router  |
                     +-----+-----+
                           |
                           |
                           |  Customer
                           |  Internet Connection
                           |
                     +-----v-----+
                     |   IPv6    |
                     |    CE     |
                     |  Router   |
                     +-----+-----+
                           |
                    +----+-+-------+
                    |              |
                    |              |
                +---+----+   +-----+------+
                |  IPv6  |   |            |
                |  Host  |   |  Router    |
                |        |   |            |
                +--------+   +------------+

5. Requirements

The IPv6 CE Router distributes configuration information obtained during WAN interface provisioning to IPv6 hosts and routers. A router based on [RFC7084] previously would only address IPv6 hosts, this update to allow for addressing and routing of routers.¶

LAN Prefix Delegation (PD) Requirements¶

LPD-1: The IPv6 CE Router MUST support DHCPv6 server capable of IPv6 prefix assignment according to [RFC8415] (Idenity Association for Prefix Delegation (IA_PD) option).¶

LPD-2: The IPv6 CE Router MUST assign addresses from the delegated prefix to the number of links. If not enough addresses are available the IPv6 CE Router SHOULD log a system management error.¶

LPD-3: The assigned addresses to a link do not change in the absence of topology or configuration changes.¶

LPD-4: After interface address assignment the IPv6 CE Router MUST make the remaining IPv6 prefixes available to other Routers via Prefix Delegation¶

LPD-5: The IPv6 CE Router MUST give out a IA_PD of the remaining prefixes with a IA_PD size of 64.¶

LPD-6: The IPv6 CE Router MUST install a route to the IA_PD assigned with a next-hop of the IPv6 node assigned the address. The IPv6 CE Router MUST remove a route when IA_PD lease expires as well.¶

LPD-7: The IPv6 CE Router firewall MUST allow traffic for Delegated Prefixes thru from WAN to LAN.¶

LPD-8: If a IPv6 CE Router recieves IPv6 prefixes of size 64 it MUST enable delegating relay according to [RFC8987] and the following requirements G-2 to G-7, G-9 and S-2.¶

6. Security Considerations

This document does not add any new security considerations beyond those mentioned in Section 4 of [RFC8213] and Section 22 of [RFC8415].¶

7. IANA Considerations

This document makes no request of IANA.¶

8. Acknowledements

Thanks to the following people for their guidance and feedback: Marion Dillon, Erik Auerswald, Esko Dijk, Ted Lemon, Michael Richardson, Martin Hunek.¶

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