Service Registration Protocol for DNS-Based Service Discovery
draft-ietf-dnssd-srp-09
Internet Engineering Task Force T. Lemon
Internet-Draft S. Cheshire
Intended status: Standards Track Apple Inc.
Expires: 15 July 2021 11 January 2021
Service Registration Protocol for DNS-Based Service Discovery
draft-ietf-dnssd-srp-09
Abstract
The Service Registration Protocol for DNS-Based Service Discovery
uses the standard DNS Update mechanism to enable DNS-Based Service
Discovery using only unicast packets. This makes it possible to
deploy DNS Service Discovery without multicast, which greatly
improves scalability and improves performance on networks where
multicast service is not an optimal choice, particularly 802.11
(Wi-Fi) and 802.15.4 (IoT) networks. DNS-SD Service registration
uses public keys and SIG(0) to allow services to defend their
registrations against attack.
Status of This Memo
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This Internet-Draft will expire on 15 July 2021.
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Please review these documents carefully, as they describe your rights
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Lemon & Cheshire Expires 15 July 2021 [Page 1]
Internet-Draft Service Registration Protocol January 2021
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Service Registration Protocol . . . . . . . . . . . . . . . . 5
2.1. Protocol Variants . . . . . . . . . . . . . . . . . . . . 5
2.1.1. Full-featured Hosts . . . . . . . . . . . . . . . . . 5
2.1.2. Constrained Hosts . . . . . . . . . . . . . . . . . . 6
2.1.3. Why two variants? . . . . . . . . . . . . . . . . . . 6
2.2. Protocol Details . . . . . . . . . . . . . . . . . . . . 6
2.2.1. What to publish . . . . . . . . . . . . . . . . . . . 7
2.2.2. Where to publish it . . . . . . . . . . . . . . . . . 7
2.2.3. How to publish it . . . . . . . . . . . . . . . . . . 8
2.2.4. How to secure it . . . . . . . . . . . . . . . . . . 9
2.2.5. Service Behavior . . . . . . . . . . . . . . . . . . 9
2.3. SRP Server Behavior . . . . . . . . . . . . . . . . . . . 12
2.3.1. Validation of Adds and Deletes . . . . . . . . . . . 12
2.3.2. Valid SRP Update Requirements . . . . . . . . . . . . 14
2.3.3. FCFS Name And Signature Validation . . . . . . . . . 15
2.3.4. SRP Update response . . . . . . . . . . . . . . . . . 16
2.3.5. Optional Behavior . . . . . . . . . . . . . . . . . . 16
3. TTL Consistency . . . . . . . . . . . . . . . . . . . . . . . 17
4. Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . 17
4.1. Cleaning up stale data . . . . . . . . . . . . . . . . . 17
5. Sleep Proxy . . . . . . . . . . . . . . . . . . . . . . . . . 19
6. Security Considerations . . . . . . . . . . . . . . . . . . . 20
6.1. Source Validation . . . . . . . . . . . . . . . . . . . . 20
6.2. SRP Server Authentication . . . . . . . . . . . . . . . . 21
6.3. Required Signature Algorithm . . . . . . . . . . . . . . 21
7. Privacy Considerations . . . . . . . . . . . . . . . . . . . 21
8. Delegation of 'service.arpa.' . . . . . . . . . . . . . . . . 21
9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 22
9.1. Registration and Delegation of 'service.arpa' as a
Special-Use Domain Name . . . . . . . . . . . . . . . . . 22
9.2. 'dnssd-srp' Service Name . . . . . . . . . . . . . . . . 22
9.3. 'dnssd-srp-tls' Service Name . . . . . . . . . . . . . . 22
9.4. Anycast Address . . . . . . . . . . . . . . . . . . . . . 23
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