idnits 2.17.1 draft-doi-roll-mpl-parameter-configuration-04.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 : ---------------------------------------------------------------------------- ** The document seems to lack a both a reference to RFC 2119 and the recommended RFC 2119 boilerplate, even if it appears to use RFC 2119 keywords. RFC 2119 keyword, line 196: '... the option. It SHOULD be 16 (without...' RFC 2119 keyword, line 232: '... Clients MAY request MPL Parameter C...' RFC 2119 keyword, line 237: '... Clients MUST discard MPL Parameter ...' RFC 2119 keyword, line 244: '...option, the node SHOULD join the MPL d...' RFC 2119 keyword, line 245: '...orwarder. Nodes SHOULD configure MPL ...' (3 more instances...) Miscellaneous warnings: ---------------------------------------------------------------------------- == The copyright year in the IETF Trust and authors Copyright Line does not match the current year -- The document date (February 13, 2014) is 3719 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(See RFCs 3967 and 4897 for information about using normative references to lower-maturity documents in RFCs) == Outdated reference: A later version (-12) exists of draft-ietf-roll-trickle-mcast-04 ** Obsolete normative reference: RFC 3315 (Obsoleted by RFC 8415) == Outdated reference: A later version (-01) exists of draft-jiang-dhc-stateless-reconfiguration-00 Summary: 2 errors (**), 0 flaws (~~), 3 warnings (==), 1 comment (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 roll Y. Doi 3 Internet-Draft TOSHIBA Corporation 4 Intended status: Standards Track M. Gillmore 5 Expires: August 17, 2014 Itron, Inc 6 February 13, 2014 8 MPL Parameter Configuration Option for DHCPv6 9 draft-doi-roll-mpl-parameter-configuration-04 11 Abstract 13 This draft is to define a way to configure MPL parameter via DHCPv6 14 option. 16 Status of this Memo 18 This Internet-Draft is submitted in full conformance with the 19 provisions of BCP 78 and BCP 79. 21 Internet-Drafts are working documents of the Internet Engineering 22 Task Force (IETF). Note that other groups may also distribute 23 working documents as Internet-Drafts. The list of current Internet- 24 Drafts is at http://datatracker.ietf.org/drafts/current/. 26 Internet-Drafts are draft documents valid for a maximum of six months 27 and may be updated, replaced, or obsoleted by other documents at any 28 time. It is inappropriate to use Internet-Drafts as reference 29 material or to cite them other than as "work in progress." 31 This Internet-Draft will expire on August 17, 2014. 33 Copyright Notice 35 Copyright (c) 2014 IETF Trust and the persons identified as the 36 document authors. All rights reserved. 38 This document is subject to BCP 78 and the IETF Trust's Legal 39 Provisions Relating to IETF Documents 40 (http://trustee.ietf.org/license-info) in effect on the date of 41 publication of this document. Please review these documents 42 carefully, as they describe your rights and restrictions with respect 43 to this document. Code Components extracted from this document must 44 include Simplified BSD License text as described in Section 4.e of 45 the Trust Legal Provisions and are provided without warranty as 46 described in the Simplified BSD License. 48 Table of Contents 50 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 51 2. MPL Parameter Configuration Option . . . . . . . . . . . . . . 3 52 2.1. Unsigned Short Floating Point . . . . . . . . . . . . . . . 4 53 2.2. MPL Parameter Configuration Option Format . . . . . . . . . 5 54 2.3. DHCPv6 Client Behavior . . . . . . . . . . . . . . . . . . 6 55 2.4. MPL Forwarder Behavior . . . . . . . . . . . . . . . . . . 6 56 2.5. DHCPv6 Server Behavior . . . . . . . . . . . . . . . . . . 7 57 2.6. DHCPv6 Relay Behavior . . . . . . . . . . . . . . . . . . . 7 58 3. IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 7 59 4. Security Considerations . . . . . . . . . . . . . . . . . . . . 7 60 5. References . . . . . . . . . . . . . . . . . . . . . . . . . . 8 61 5.1. Normative References . . . . . . . . . . . . . . . . . . . 8 62 5.2. Non-Normative References . . . . . . . . . . . . . . . . . 8 63 Appendix A. Update History . . . . . . . . . . . . . . . . . . . . 8 64 Appendix B. Acknowledgements . . . . . . . . . . . . . . . . . . . 9 65 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 9 67 1. Introduction 69 Multicast Protocol for Low power and Lossy Networks (MPL) 70 [I-D.ietf-roll-trickle-mcast] defines a protocol to make a multicast 71 network among low power and lossy network i.e. wireless mesh 72 networks. MPL has various parameters to control its behavior and 73 tradeoff between end-to-end delay and network utilization. In some 74 environments, the parameters shall be configured carefully to meet 75 each environment and requirement. According to the MPL draft section 76 5.4, the parameter should be same for all nodes within an MPL domain. 77 And the MPL draft does not define a method to configure it. 79 Some managed wireless mesh networks may have a DHCP server to 80 configure network parameters with DHCP relay in each node. MPL 81 parameters shall be considered as a part of network parameters 82 (parameter shall match within an MPL domain). This document is to 83 define the way to distribute parameters for MPL forwarders as a 84 simple DHCPv6 [RFC3315] option. 86 2. MPL Parameter Configuration Option 88 Per MPL domain, there are following 10 parameters. An MPL domain is 89 defined by an MPL domain address. 91 o PROACTIVE_FORWARDING 93 o SEED_SET_ENTRY_LIFETIME 95 o DATA_MESSAGE_IMIN 97 o DATA_MESSAGE_IMAX 99 o DATA_MESSAGE_K 101 o DATA_MESSAGE_TIMER_EXPIRATIONS 103 o CONTROL_MESSAGE_IMIN 105 o CONTROL_MESSAGE_IMAX 107 o CONTROL_MESSAGE_K 109 o CONTROL_MESSAGE_TIMER_EXPIRATIONS 111 One network may have multiple MPL domains with different 112 configuration. To configure plural of MPL domains via DHCP, there 113 may be more than one MPL Parameter Configuration Option given to DHCP 114 clients from a DHCP server. 116 2.1. Unsigned Short Floating Point 118 MPL has many timer parameters. Expected range of the timers depends 119 on the network topology or MAC/PHY nature. To accommodate wide range 120 of timer values efficiently, the MPL Parameter Configuration Option 121 uses base-10 unsigned short floating point number with 3-bit exponent 122 and 13-bit significand defined as follows (exp. stands for exponent). 124 0 1 125 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 126 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 127 | exp.| significand | 128 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 130 The represented value is (significand) * 10^(exp.). Minimum exponent 131 is 0 (binary 000) and maximum is 6 (binary 110). exp=7 (binary 111) 132 is reserved for future use. Minimum significand is 0 (all 0) and 133 maximum is 8191 (all 1). 135 Unlike IEEE754 half precision floating point (binary16), there is no 136 sign bit (no negative value for a timer), exponent is not biased (no 137 fractional value for a timer), no implicit leading 1 in siginificand, 138 and base is 10. Therefore, there could be more than one 139 representation for a value. 141 Followings are examples of common timer values represented by unit of 142 milliseconds. 144 One second (1,000 ms.): exp = 3, significand = 1. 0x6001. 146 One minute (60,000 ms.): exp = 4, significand = 6, 0x8006. 148 One hour (3,600,000 ms.): exp = 5, significand = 36, 0xa024. 150 One day (86,400,000 ms.): exp = 5, significand = 864, 0xa360 152 Maximum timer length represented by unsigned short floating point 153 with millisecond precision is 8191*10^6 milliseconds (13 weeks 3 days 154 19 hours 16 minutes 40 seconds). 156 With exponent and significand, an unsigned short floating point 157 (usfp) can be encoded as follows. 159 usfp = (exponent << 13)|(0x1fff & significand); 161 2.2. MPL Parameter Configuration Option Format 163 To distribute a configuration of an MPL domain or a default value for 164 all MPL domains (wildcard) under the network managed by the DHCP 165 server, this document defines a DHCPv6 option format as follows. 166 Short floating point format is used to describe wide range of timer 167 values. 169 0 1 2 3 170 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 1 171 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 172 | OPTION_MPL_PARAMETERS | option_len | 173 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 174 |P| Z | C_K | Z2 | DM_K | SE_LIFETIME | 175 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 176 | DM_IMIN | DM_IMAX | 177 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 178 | DM_T_EXP | C_IMIN | 179 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 180 | C_IMAX | C_T_EXP | 181 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 183 (if option_len = 32 ) 184 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 185 | MPL Domain Address (128bits) | 186 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 187 | (cont'ed) | 188 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 189 | (cont'ed) | 190 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 191 | (cont'ed) | 192 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 194 OPTION_MPL_PARAMETERS: not yet assigned. 196 option_len: Length of the option. It SHOULD be 16 (without MPL 197 domain address) or 32 (with MPL domain address) 199 P (1 bit): A flag to indicate PROACTIVE_FORWARDING 201 Z (1 bit) Reserved. Should be 0. 203 C_K (5 bits): Value of CONTROL_MESSAGE_K. 205 Z2 (3 bit) Reserved. Should be all 0. 207 DM_K (5 bits): Value of DATA_MESSAGE_K. 209 SE_LIFETIME: SEED_SET_ENTRY_LIFETIME. The value is milliseconds in 210 unsigned short floating point. 212 DM_IMIN: Value of DATA_MESSAGE_IMIN. The value is milliseconds in 213 unsigned short floating point. 215 DM_IMAX: Value of DATA_MESSAGE_IMAX. The value is milliseconds in 216 unsigned short floating point. 218 DM_T_EXP: Value of DATA_MESSAGE_TIMER_EXPIRATIONS. The value is 219 milliseconds in unsigned short floating point. 221 C_IMIN: Value of CONTROL_MESSAGE_IMIN. The value is milliseconds in 222 unsigned short floating point. 224 C_IMAX: Value of CONTROL_MESSAGE_IMAX. The value is milliseconds in 225 unsigned short floating point. 227 C_T_EXP: Value of CONTROL_MESSAGE_TIMER_EXPIRATIONS. The value is 228 milliseconds in unsigned short floating point. 230 2.3. DHCPv6 Client Behavior 232 Clients MAY request MPL Parameter Configuration Option, as described 233 in RFC3315 [RFC3315], sections 17.1.1, 18.1.1, 18.1.3, 18.1.4, 18.1.5 234 and 22.7. As a convenience to the reader, we mention here that the 235 client includes requested option codes in Option Request Option. 237 Clients MUST discard MPL Parameter Configuration Option if it is 238 invalid (i.e. it sets reserved bits or it has timers with reserved 239 exp=7 in Unsigned Short Floating Point). 241 2.4. MPL Forwarder Behavior 243 If a DHCPv6 client requests and receives MPL parameter configuration 244 option, the node SHOULD join the MPL domain given by the option and 245 act as an MPL forwarder. Nodes SHOULD configure MPL forwarders with 246 the given parameters when it joins to the MPL domain. 248 The priority of MPL Parameter configuration applied for an MPL Domain 249 is as follows (high to low). 251 o Specific MPL Parameter Configuration to the MPL Domain (optlen=32) 253 o Wildcard MPL Parameter Configuration (optlen=16) 254 o Default configuration given in the MPL specification. 256 There SHALL be no more than one MPL parameter configuration option 257 for a MPL domain or the wildcard. Thus, the order of DHCPv6 option 258 in the packet has no effect on precedence. 260 A node MAY leave from an MPL domain if the node is attached to the 261 MPL domain according to previously received MPL parameter 262 configuration option, and, the node received updated MPL parameter 263 configuration option without specific configuration option for the 264 MPL domain. 266 MPL parameter may be updated occasionally. With stateful DHCPv6, 267 updates can be done when the renewal timer expires. However, on 268 stateless DHCPv6 there are no way to update the parameters properly. 269 There is a DHCPv6 option to push updates 270 [I-D.jiang-dhc-stateless-reconfiguration]. 272 2.5. DHCPv6 Server Behavior 274 Sections 17.2.2 and 18.2 of RFC3315 [RFC3315] govern server operation 275 in regards to option assignment. As a convenience to the reader, we 276 mention here that the server will send MPL Parameter Configuration 277 Option only if configured with specific value for MPL Parameter 278 Configuration Option and the client requested it. 280 Servers MUST ignore incoming MPL Parameter Configuration Option. 282 2.6. DHCPv6 Relay Behavior 284 It's never appropriate for a relay agent to add options to a message 285 heading toward the client, and relay agents don't actually construct 286 Relay-Reply messages anyway. There are no additional requirements 287 for relays. 289 3. IANA Considerations 291 A DHCPv6 option code for MPL Parameter Configuration Option needs to 292 be assigned from IANA. 294 4. Security Considerations 296 Forged option may cause too many MAC broadcasting. Reasonable bound 297 of parameters (not too high K, not too low IMIN) may be defined by 298 implementations or derived from MAC/PHY specifications. DHCP server 299 or the network itself shall be trusted by some means including 300 network access control or DHCP authentications. 302 5. References 304 5.1. Normative References 306 [I-D.ietf-roll-trickle-mcast] 307 Hui, J. and R. Kelsey, "Multicast Forwarding Using 308 Trickle", draft-ietf-roll-trickle-mcast-04 (work in 309 progress), Feburary 2013. 311 [RFC3315] Droms, R., Bound, J., Volz, B., Lemon, T., Perkins, C., 312 and M. Carney, "Dynamic Host Configuration Protocol for 313 IPv6 (DHCPv6)", RFC 3315, July 2003. 315 5.2. Non-Normative References 317 [I-D.jiang-dhc-stateless-reconfiguration] 318 Jiang, S. and B. Liu, "Stateless Reconfiguration in 319 Dynamic Host Configuration Protocol for IPv6 (DHCPv6)", 320 draft-jiang-dhc-stateless-reconfiguration-00 (work in 321 progress), October 2013. 323 Appendix A. Update History 325 Updates on 03 to 04: 327 o Added more sections according to dhc-options-guidelines 329 o Removed 'no update' requirement on MPL forwarder behavior 331 o Added reference to I-D.jiang-dhc-stateless-reconfiguration 333 Updates on 02 to 03: 335 o C flag is removed and wildcard shall be identified by optlen 337 o Added some description on update of MPL parameters 339 o Clearly stated there shall not be two or more configuration for an 340 MPL domain and option order is not significant. 342 Updates on 01 to 02: 344 o Added co-author 346 Updates on 00 to 01: 348 o Corrected target area, track, etc. 350 Appendix B. Acknowledgements 352 The authors thank Richard Kelsey and Yoshi Ohba for technical advices 353 to improve this draft. 355 Authors' Addresses 357 Yusuke Doi 358 TOSHIBA Corporation 359 Komukai Toshiba Cho 1 360 Saiwai-Ku 361 Kawasaki, Kanagawa 2128582 362 JAPAN 364 Phone: +81-45-342-7230 365 Email: yusuke.doi@toshiba.co.jp 366 URI: 368 Matthew Gillmore 369 Itron, Inc 370 2111 N Molter Rd. 371 Liberty Lake, WA 99019 372 USA 374 Email: matthew.gillmore@itron.com