Softwire Provisioning Using DHCPv4 over DHCPv6
RFC 8539
| Document | Type |
RFC - Proposed Standard
(March 2019; No errata)
Updates RFC 7598
|
|
|---|---|---|---|
| Last updated | 2019-03-15 | ||
| Replaces | draft-fsc-softwire-dhcp4o6-saddr-opt | ||
| Stream | IETF | ||
| Formats | plain text pdf html bibtex | ||
| Reviews | |||
| Stream | WG state | Submitted to IESG for Publication | |
| Document shepherd | Bernie Volz | ||
| Shepherd write-up | Show (last changed 2018-06-21) | ||
| IESG | IESG state | RFC 8539 (Proposed Standard) | |
| Consensus Boilerplate | Yes | ||
| Telechat date | |||
| Responsible AD | Suresh Krishnan | ||
| Send notices to | Bernie Volz <volz@cisco.com> | ||
| IANA | IANA review state | IANA OK - Actions Needed | |
| IANA action state | RFC-Ed-Ack | ||
Internet Engineering Task Force (IETF) I. Farrer
Request for Comments: 8539 Deutsche Telekom AG
Updates: 7598 Q. Sun
Category: Standards Track Y. Cui
ISSN: 2070-1721 L. Sun
Tsinghua University
March 2019
Softwire Provisioning Using DHCPv4 over DHCPv6
Abstract
DHCPv4 over DHCPv6 (RFC 7341) is a mechanism for dynamically
configuring IPv4 for use as an over-the-top service in an IPv6-only
network. Softwires are an example of such a service. For DHCPv4
over DHCPv6 (DHCP 4o6) to function with some IPv4-over-IPv6 softwire
mechanisms and deployment scenarios (e.g., RFC 7596 or RFC 7597), the
operator needs to know the IPv6 address that the client will use as
the source of an IPv4-in-IPv6 softwire tunnel. This address, in
conjunction with the client's IPv4 address, and (in some deployments)
the Port Set ID are used to create a binding table entry in the
operator's softwire tunnel concentrator. This memo defines a DHCPv6
option to convey IPv6 parameters for establishing the softwire tunnel
and a DHCPv4 option (to be used only with DHCP 4o6) to communicate
the source tunnel IPv6 address between the DHCP 4o6 client and
server. It is designed to work in conjunction with the IPv4 address
allocation process.
"DHCPv6 Options for Configuration of Softwire Address and Port-Mapped
Clients" (RFC 7598) describes a deterministic DHCPv6-based mechanism
for provisioning softwires. This document updates RFC 7598, allowing
OPTION_S46_BR (90) to be enumerated in the DHCPv6 client's Option
Request Option (ORO) request and to appear directly within subsequent
messages sent by the DHCPv6 server.
Farrer, et al. Standards Track [Page 1]
RFC 8539 Softwire Provisioning with DHCP 4o6 March 2019
Status of This Memo
This is an Internet Standards Track document.
This document is a product of the Internet Engineering Task Force
(IETF). It represents the consensus of the IETF community. It has
received public review and has been approved for publication by the
Internet Engineering Steering Group (IESG). Further information on
Internet Standards is available in Section 2 of RFC 7841.
Information about the current status of this document, any errata,
and how to provide feedback on it may be obtained at
https://www.rfc-editor.org/info/rfc8539.
Copyright Notice
Copyright (c) 2019 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(https://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Farrer, et al. Standards Track [Page 2]
RFC 8539 Softwire Provisioning with DHCP 4o6 March 2019
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Applicability . . . . . . . . . . . . . . . . . . . . . . . . 4
3. Requirements Language . . . . . . . . . . . . . . . . . . . . 4
4. Solution Overview . . . . . . . . . . . . . . . . . . . . . . 5
4.1. Updating RFC 7598 to Permit the Reuse of
OPTION_S46_BR (90) . . . . . . . . . . . . . . . . . . . 5
5. DHCP 4o6 IPv6/IPv4 Binding Message Flow . . . . . . . . . . . 6
6. DHCP Options . . . . . . . . . . . . . . . . . . . . . . . . 7
6.1. DHCPv6 Softwire Source Binding Prefix Hint Option . . . . 7
6.2. DHCP 4o6 Softwire Source Address Option . . . . . . . . . 8
7. Client Behavior . . . . . . . . . . . . . . . . . . . . . . . 9
7.1. Client Initialization . . . . . . . . . . . . . . . . . . 9
7.2. Renewing or Rebinding the IPv4 Address Lease and
Softwire Source Address . . . . . . . . . . . . . . . . . 10
7.2.1. Changing the Bound IPv6 Softwire Source Address . . . 10
7.3. Releasing the IPv4 Address Lease and Softwire
Source Address . . . . . . . . . . . . . . . . . . . . . 11
7.4. OPTION_S46_BIND_IPV6_PREFIX Validation Behavior . . . . . 11
7.5. Client and Server Softwire Source Address Mismatch . . . 11
7.6. Use with Dynamic, Shared IPv4 Addresses . . . . . . . . . 12
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