Neighbor Cache Entries on First-Hop Routers: Operational Considerations
draft-ietf-v6ops-nd-cache-init-00
v6ops J. Linkova
Internet-Draft Google
Intended status: Informational October 27, 2019
Expires: April 29, 2020
Neighbor Cache Entries on First-Hop Routers: Operational Considerations
draft-ietf-v6ops-nd-cache-init-00
Abstract
Neighbor Discovery (RFC4861) is used by IPv6 nodes to determine the
link-layer addresses of neighboring nodes as well as to discover and
maintain reachability information. This document discusses how the
neighbor discovery state machine on a first-hop router is causing
user-visible connectivity issues when a new (not being seen on the
network before) IPv6 address is being used.
Status of This Memo
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provisions of BCP 78 and BCP 79.
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Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on April 29, 2020.
Copyright Notice
Copyright (c) 2019 IETF Trust and the persons identified as the
document authors. All rights reserved.
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Linkova Expires April 29, 2020 [Page 1]
Internet-Draft NC Entries Creation October 2019
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Requirements Language . . . . . . . . . . . . . . . . . . 4
1.2. Terminology . . . . . . . . . . . . . . . . . . . . . . . 4
2. Potential Solutions . . . . . . . . . . . . . . . . . . . . . 5
2.1. Do Nothing . . . . . . . . . . . . . . . . . . . . . . . 5
2.1.1. Pros . . . . . . . . . . . . . . . . . . . . . . . . 5
2.1.2. Cons . . . . . . . . . . . . . . . . . . . . . . . . 5
2.2. Change to the Registration-Based Neighbor Discovery . . . 6
2.3. Hosts Explicitly Advertizing Their GUAs Using Existing ND
Mechanisms . . . . . . . . . . . . . . . . . . . . . . . 6
2.3.1. Host Sending Unsolicited NA . . . . . . . . . . . . . 6
2.3.1.1. Pros . . . . . . . . . . . . . . . . . . . . . . 7
2.3.1.2. Cons . . . . . . . . . . . . . . . . . . . . . . 7
2.3.2. Host Sending NS to the Router Address from Its GUA . 7
2.3.2.1. Pros . . . . . . . . . . . . . . . . . . . . . . 8
2.3.2.2. Cons . . . . . . . . . . . . . . . . . . . . . . 8
2.3.3. Host Sending Router Solicitation from its GUA . . . . 8
2.3.3.1. Pros . . . . . . . . . . . . . . . . . . . . . . 8
2.3.3.2. Cons . . . . . . . . . . . . . . . . . . . . . . 8
2.4. Routers Populating Their Caches by Gleaning From Neighbor
Discovery Packets . . . . . . . . . . . . . . . . . . . . 9
2.4.1. Pros . . . . . . . . . . . . . . . . . . . . . . . . 9
2.4.2. Cons . . . . . . . . . . . . . . . . . . . . . . . . 9
2.5. Initiating Hosts2Routers Communication . . . . . . . . . 9
2.5.1. Pros . . . . . . . . . . . . . . . . . . . . . . . . 10
2.5.2. Cons . . . . . . . . . . . . . . . . . . . . . . . . 10
2.6. Tweaking Probing Algorithms . . . . . . . . . . . . . . . 10
2.7. Routers Buffering More Packets . . . . . . . . . . . . . 10
2.7.1. Pros . . . . . . . . . . . . . . . . . . . . . . . . 10
2.7.2. Cons . . . . . . . . . . . . . . . . . . . . . . . . 11
3. Recommendations . . . . . . . . . . . . . . . . . . . . . . . 11
4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 11
5. Security Considerations . . . . . . . . . . . . . . . . . . . 11
6. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 11
7. References . . . . . . . . . . . . . . . . . . . . . . . . . 12
7.1. Normative References . . . . . . . . . . . . . . . . . . 12
7.2. Informative References . . . . . . . . . . . . . . . . . 13
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