idnits 2.17.1 draft-ietf-dhc-relay-id-suboption-10.txt: Checking boilerplate required by RFC 5378 and the IETF Trust (see https://trustee.ietf.org/license-info): ---------------------------------------------------------------------------- No issues found here. Checking nits according to https://www.ietf.org/id-info/1id-guidelines.txt: ---------------------------------------------------------------------------- No issues found here. Checking nits according to https://www.ietf.org/id-info/checklist : ---------------------------------------------------------------------------- No issues found here. Miscellaneous warnings: ---------------------------------------------------------------------------- == The copyright year in the IETF Trust and authors Copyright Line does not match the current year -- The document seems to lack a disclaimer for pre-RFC5378 work, but may have content which was first submitted before 10 November 2008. If you have contacted all the original authors and they are all willing to grant the BCP78 rights to the IETF Trust, then this is fine, and you can ignore this comment. If not, you may need to add the pre-RFC5378 disclaimer. (See the Legal Provisions document at https://trustee.ietf.org/license-info for more information.) -- The document date (January 10, 2012) is 4488 days in the past. Is this intentional? Checking references for intended status: Proposed Standard ---------------------------------------------------------------------------- (See RFCs 3967 and 4897 for information about using normative references to lower-maturity documents in RFCs) == Missing Reference: 'TBA' is mentioned on line 204, but not defined == Outdated reference: A later version (-07) exists of draft-ietf-dhc-dhcpv4-bulk-leasequery-05 Summary: 0 errors (**), 0 flaws (~~), 3 warnings (==), 2 comments (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 DHC B. Joshi 3 Internet-Draft D. Ramakrishna Rao 4 Intended status: Standards Track Infosys Ltd. 5 Expires: July 13, 2012 M. Stapp 6 Cisco Systems, Inc. 7 January 10, 2012 9 The DHCPv4 Relay Agent Identifier Suboption 10 draft-ietf-dhc-relay-id-suboption-10.txt 12 Abstract 14 This draft defines a new Relay Agent Identifier suboption for the 15 Dynamic Host Configuration Protocol's (DHCP) Relay Agent Information 16 option. The suboption carries a value that uniquely identifies the 17 relay agent device within the administrative domain. The value is 18 normally administratively-configured in the relay agent. The 19 suboption allows a DHCP relay agent to include the identifier in the 20 DHCP messages it sends. 22 Status of this Memo 24 This Internet-Draft is submitted in full conformance with the 25 provisions of BCP 78 and BCP 79. 27 Internet-Drafts are working documents of the Internet Engineering 28 Task Force (IETF). Note that other groups may also distribute 29 working documents as Internet-Drafts. The list of current Internet- 30 Drafts is at http://datatracker.ietf.org/drafts/current/. 32 Internet-Drafts are draft documents valid for a maximum of six months 33 and may be updated, replaced, or obsoleted by other documents at any 34 time. It is inappropriate to use Internet-Drafts as reference 35 material or to cite them other than as "work in progress." 37 This Internet-Draft will expire on July 13, 2012. 39 Copyright Notice 41 Copyright (c) 2012 IETF Trust and the persons identified as the 42 document authors. All rights reserved. 44 This document is subject to BCP 78 and the IETF Trust's Legal 45 Provisions Relating to IETF Documents 46 (http://trustee.ietf.org/license-info) in effect on the date of 47 publication of this document. Please review these documents 48 carefully, as they describe your rights and restrictions with respect 49 to this document. Code Components extracted from this document must 50 include Simplified BSD License text as described in Section 4.e of 51 the Trust Legal Provisions and are provided without warranty as 52 described in the Simplified BSD License. 54 Table of Contents 56 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 57 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . . 3 58 3. Example Use-Cases . . . . . . . . . . . . . . . . . . . . . . . 3 59 3.1. Bulk Leasequery . . . . . . . . . . . . . . . . . . . . . . 3 60 3.2. Industrial Ethernet . . . . . . . . . . . . . . . . . . . . 3 61 4. Suboption Format . . . . . . . . . . . . . . . . . . . . . . . 4 62 5. Identifier Stability . . . . . . . . . . . . . . . . . . . . . 4 63 6. Security Considerations . . . . . . . . . . . . . . . . . . . . 5 64 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 5 65 8. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . 6 66 9. References . . . . . . . . . . . . . . . . . . . . . . . . . . 6 67 9.1. Normative References . . . . . . . . . . . . . . . . . . . 6 68 9.2. Informative References . . . . . . . . . . . . . . . . . . 6 69 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 6 71 1. Introduction 73 The Dynamic Host Configuration Protocol for IPv4 (DHCPv4) [RFC2131] 74 provides IP addresses and configuration information for IPv4 clients. 75 It includes a relay agent capability, in which network elements 76 receive broadcast messages from clients and forward them to DHCP 77 servers as unicast messages. In many network environments, relay 78 agents add information to the DHCP messages before forwarding them, 79 using the Relay Agent Information option [RFC3046]. Servers that 80 recognize the relay agent information option echo it back in their 81 replies. 83 This specification introduces a Relay Agent Identifier suboption for 84 the Relay Agent Information option. The Relay-Id suboption carries a 85 sequence of octets that is intended to uniquely identify the relay 86 agent within the administrative domain. 88 2. Terminology 90 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 91 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 92 document are to be interpreted as described in [RFC2119]. 94 DHCPv4 terminology is defined in [RFC2131], and the DHCPv4 Relay 95 Agent Information Option in [RFC3046]. 97 3. Example Use-Cases 99 3.1. Bulk Leasequery 101 There has been quite a bit of recent interest in extending the DHCP 102 Leasequery protocol [RFC4388] to accommodate some additional 103 situations. There is a recent draft 104 ([I-D.ietf-dhc-dhcpv4-bulk-leasequery] proposing a variety of 105 enhancements to the existing Leasequery protocol. The draft 106 describes a use-case where a relay agent queries DHCP servers using 107 the Relay Identifier to retrieve all the leases allocated through the 108 relay agent. 110 3.2. Industrial Ethernet 112 DHCP typically identifies clients based on information in their DHCP 113 messages - such as the Client-Identifier option, or the value of the 114 chaddr field. In some networks, however, the location of a client - 115 its point of attachment to the network - is a more useful identifier. 116 In factory-floor networks (commonly called 'Industrial' networks), 117 for example, the role a device plays is often fixed and based on its 118 location. Using manual address configuration is possible (and is 119 common) but it would be beneficial if DHCP configuration could be 120 applied to these networks. 122 One way to provide connection-based identifiers for industrial 123 networks is to have the network elements acting as DHCP relay agents 124 supply information that a DHCP server could use as a client 125 identifier. A straightforward way to form identifier information is 126 to combine something that is unique within the scope of the network 127 element, such as a port/slot value, with something that uniquely 128 identifies that network element, such as a Relay Agent Identifier. 130 4. Suboption Format 132 Format of the Relay Agent Identifier suboption: 134 0 1 2 3 135 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 136 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 137 |SUBOPT_RELAY_ID| length | | 138 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | 139 . . 140 . identifier (variable) . 141 . . 142 +---------------------------------------------------------------+ 144 Where: 146 SUBOPT_RELAY_ID [TBA] 148 length the number of octets in the suboption 149 (excluding the suboption ID and length fields); 150 the minimum length is one. 152 identifier the identifying data. 154 5. Identifier Stability 156 If the relay identifier is to be meaningful it has to be stable. A 157 relay agent SHOULD use a single identifier value consistently. The 158 identifier used by a relay device SHOULD be committed to stable 159 storage, unless the relay device can regenerate the value upon 160 reboot. 162 Administrators MUST make sure that the relay-id configured in a relay 163 agent is unique within their administrative domain. To aid this, 164 relay agents SHOULD make their relay identifiers visible to their 165 administrators via their user interface, through a log entry, or 166 through some other mechanism. 168 Implementors should note that the identifier needs to be present in 169 all DHCP message types where its value is being used by the DHCP 170 server. The relay agent may not be able to add the Relay Agent 171 Information option to all messages - such as RENEW messages sent as 172 IP unicasts. In some deployments that might mean that the server has 173 to be willing to continue to associate the relay identifier it has 174 last seen with a lease that is being RENEWed. Other deployments may 175 prefer to use the Server Identifier Override suboption [RFC5107] to 176 permit the relay device to insert the Relay Agent Information option 177 into all relayed messages. 179 Handling situations where a relay agent device is replaced is another 180 aspect of "stability". One of the use-cases for the relay identifier 181 is to permit a server to associate clients' lease bindings with the 182 relay device connected to the clients. If the relay device is 183 replaced, because it has failed or been upgraded, it may be desirable 184 for the new device to continue to provide the same relay identifier 185 as the old device. Implementors should be aware of this possibility, 186 and consider making it possible for administrators to configure the 187 identifier. 189 6. Security Considerations 191 Security issues with the Relay Agent Information option and its use 192 by servers in address assignment are discussed in [RFC3046] and 193 [RFC4030]. Relay agents who send the Relay Agent Identifier 194 suboption SHOULD use the Relay Agent Authentication suboption 195 [RFC4030] to provide integrity protection and to avoid duplication of 196 relay identifiers by malicious entities. 198 7. IANA Considerations 200 We request that IANA assign a new suboption code from the registry of 201 DHCP Agent Sub-Option Codes maintained in 202 http://www.iana.org/assignments/bootp-dhcp-parameters. 204 Relay Agent Identifier Suboption [TBA] 206 8. Acknowledgments 208 Thanks to Bernie Volz, David W. Hankins, Pavan Kurapati and Ted Lemon 209 for providing valuable suggestions. 211 9. References 213 9.1. Normative References 215 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 216 Requirement Levels", BCP 14, RFC 2119, March 1997. 218 [RFC2131] Droms, R., "Dynamic Host Configuration Protocol", 219 RFC 2131, March 1997. 221 [RFC3046] Patrick, M., "DHCP Relay Agent Information Option", 222 RFC 3046, January 2001. 224 [RFC4030] Stapp, M. and T. Lemon, "The Authentication Suboption for 225 the Dynamic Host Configuration Protocol (DHCP) Relay Agent 226 Option", RFC 4030, March 2005. 228 9.2. Informative References 230 [RFC4388] Woundy, R. and K. Kinnear, "Dynamic Host Configuration 231 Protocol (DHCP) Leasequery", RFC 4388, February 2006. 233 [RFC5107] Johnson, R., Kumarasamy, J., Kinnear, K., and M. Stapp, 234 "DHCP Server Identifier Override Suboption", RFC 5107, 235 February 2008. 237 [I-D.ietf-dhc-dhcpv4-bulk-leasequery] 238 Kinnear, K., Volz, B., Stapp, M., Joshi, B., Russell, N., 239 and P. Kurapati, "Bulk DHCPv4 Lease Query", 240 draft-ietf-dhc-dhcpv4-bulk-leasequery-05 (work in 241 progress), November 2011. 243 Authors' Addresses 245 Bharat Joshi 246 Infosys Ltd. 247 44 Electronics City, Hosur Road 248 Bangalore 560 100 249 India 251 Email: bharat_joshi@infosys.com 252 URI: http://www.infosys.com/ 254 D.T.V Ramakrishna Rao 255 Infosys Ltd. 256 44 Electronics City, Hosur Road 257 Bangalore 560 100 258 India 260 Email: ramakrishnadtv@infosys.com 261 URI: http://www.infosys.com/ 263 Mark Stapp 264 Cisco Systems, Inc. 265 1414 Massachusetts Ave. 266 Boxborough, MA 01719 267 USA 269 Phone: +1 978 936 0000 270 Email: mjs@cisco.com