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Checking references for intended status: Informational ---------------------------------------------------------------------------- == Outdated reference: draft-ietf-emu-eap-tls13 has been published as RFC 9190 == Outdated reference: draft-ietf-tls-certificate-compression has been published as RFC 8879 == Outdated reference: A later version (-05) exists of draft-ietf-tls-ctls-00 -- Obsolete informational reference (is this intentional?): RFC 5246 (Obsoleted by RFC 8446) -- Obsolete informational reference (is this intentional?): RFC 7049 (Obsoleted by RFC 8949) Summary: 0 errors (**), 0 flaws (~~), 4 warnings (==), 3 comments (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 Network Working Group M. Sethi 3 Internet-Draft J. Mattsson 4 Intended status: Informational Ericsson 5 Expires: May 1, 2021 S. Turner 6 sn3rd 7 October 28, 2020 9 Handling Large Certificates and Long Certificate Chains 10 in TLS-based EAP Methods 11 draft-ietf-emu-eaptlscert-06 13 Abstract 15 The Extensible Authentication Protocol (EAP), defined in RFC3748, 16 provides a standard mechanism for support of multiple authentication 17 methods. EAP-Transport Layer Security (EAP-TLS) and other TLS-based 18 EAP methods are widely deployed and used for network access 19 authentication. Large certificates and long certificate chains 20 combined with authenticators that drop an EAP session after only 40 - 21 50 round-trips is a major deployment problem. This document looks at 22 the this problem in detail and describes the potential solutions 23 available. 25 Status of This Memo 27 This Internet-Draft is submitted in full conformance with the 28 provisions of BCP 78 and BCP 79. 30 Internet-Drafts are working documents of the Internet Engineering 31 Task Force (IETF). Note that other groups may also distribute 32 working documents as Internet-Drafts. The list of current Internet- 33 Drafts is at https://datatracker.ietf.org/drafts/current/. 35 Internet-Drafts are draft documents valid for a maximum of six months 36 and may be updated, replaced, or obsoleted by other documents at any 37 time. It is inappropriate to use Internet-Drafts as reference 38 material or to cite them other than as "work in progress." 40 This Internet-Draft will expire on May 1, 2021. 42 Copyright Notice 44 Copyright (c) 2020 IETF Trust and the persons identified as the 45 document authors. All rights reserved. 47 This document is subject to BCP 78 and the IETF Trust's Legal 48 Provisions Relating to IETF Documents 49 (https://trustee.ietf.org/license-info) in effect on the date of 50 publication of this document. Please review these documents 51 carefully, as they describe your rights and restrictions with respect 52 to this document. Code Components extracted from this document must 53 include Simplified BSD License text as described in Section 4.e of 54 the Trust Legal Provisions and are provided without warranty as 55 described in the Simplified BSD License. 57 Table of Contents 59 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 60 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3 61 3. Experience with Deployments . . . . . . . . . . . . . . . . . 4 62 4. Handling of Large Certificates and Long Certificate Chains . 5 63 4.1. Updating Certificates and Certificate Chains . . . . . . 5 64 4.1.1. Guidelines for Certificates . . . . . . . . . . . . . 5 65 4.1.2. Pre-distributing and Omitting CA certificates . . . . 7 66 4.1.3. Using Fewer Intermediate Certificates . . . . . . . . 7 67 4.2. Updating TLS and EAP-TLS Code . . . . . . . . . . . . . . 7 68 4.2.1. URLs for Client Certificates . . . . . . . . . . . . 7 69 4.2.2. Caching Certificates . . . . . . . . . . . . . . . . 8 70 4.2.3. Compressing Certificates . . . . . . . . . . . . . . 8 71 4.2.4. Compact TLS 1.3 . . . . . . . . . . . . . . . . . . . 9 72 4.2.5. Suppressing Intermediate Certificates . . . . . . . . 9 73 4.2.6. Raw Public Keys . . . . . . . . . . . . . . . . . . . 9 74 4.2.7. New Certificate Types and Compression Algorithms . . 9 75 4.3. Updating Authenticators . . . . . . . . . . . . . . . . . 10 76 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 10 77 6. Security Considerations . . . . . . . . . . . . . . . . . . . 10 78 7. References . . . . . . . . . . . . . . . . . . . . . . . . . 11 79 7.1. Normative References . . . . . . . . . . . . . . . . . . 11 80 7.2. Informative References . . . . . . . . . . . . . . . . . 12 81 Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 13 82 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 14 84 1. Introduction 86 The Extensible Authentication Protocol (EAP), defined in [RFC3748], 87 provides a standard mechanism for support of multiple authentication 88 methods. EAP-Transport Layer Security (EAP-TLS) [RFC5216] 89 [I-D.ietf-emu-eap-tls13] relies on TLS [RFC8446] to provide strong 90 mutual authentication with certificates [RFC5280] and is widely 91 deployed and often used for network access authentication. There are 92 also many other TLS-based EAP methods, such as Flexible 93 Authentication via Secure Tunneling (EAP-FAST) [RFC4851], Tunneled 94 Transport Layer Security (EAP-TTLS) [RFC5281], Tunnel Extensible 95 Authentication Protocol (EAP-TEAP) [RFC7170], and possibly many 96 vendor specific EAP methods. 98 Certificates in EAP deployments can be relatively large, and the 99 certificate chains can be long. Unlike the use of TLS on the web, 100 where typically only the TLS server is authenticated; EAP-TLS 101 deployments typically authenticates both the EAP peer and the EAP 102 server. Also, from deployment experience, EAP peers typically have 103 longer certificate chains than servers. This is because EAP peers 104 often follow organizational hierarchies and tend to have many 105 intermediate certificates. Thus, EAP-TLS authentication usually 106 involves exchange of significantly more octets than when TLS is used 107 as part of HTTPS. 109 Section 3.1 of [RFC3748] states that EAP implementations can assume a 110 MTU of at least 1020 octets from lower layers. The EAP fragment size 111 in typical deployments is just 1020 - 1500 octets (since the maximum 112 Ethernet frame size is ~ 1500 bytes). Thus, EAP-TLS authentication 113 needs to be fragmented into many smaller packets for transportation 114 over the lower layers. Such fragmentation can not only negatively 115 affect the latency, but also results in other challenges. For 116 example, some EAP authenticator (access point) implementations will 117 drop an EAP session if it has not finished after 40 - 50 round-trips. 118 This is a major problem and means that in many situations, the EAP 119 peer cannot perform network access authentication even though both 120 the sides have valid credentials for successful authentication and 121 key derivation. 123 Not all EAP deployments are constrained by the MTU of the lower 124 layer. For example, some implementations support EAP over Ethernet 125 "Jumbo" frames that can easily allow very large EAP packets. Larger 126 packets will naturally help lower the number of round trips required 127 for successful EAP-TLS authentication. However, deployment 128 experience has shown that these jumbo frames are not always 129 implemented correctly. Additionally, EAP fragment size is also 130 restricted by protocols such as RADIUS [RFC2865] which are 131 responsible for transporting EAP messages between an authenticator 132 and an EAP server. RADIUS can generally transport only about 4000 133 octets of EAP in a single message (the maximum length of RADIUS 134 packet is restricted to 4096 octets in [RFC2865]). 136 This document looks at related work and potential tools available for 137 overcoming the deployment challenges induced by large certificates 138 and long certificate chains. It then discusses the solutions 139 available to overcome these challenges. 141 2. Terminology 143 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 144 "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and 145 "OPTIONAL" in this document are to be interpreted as described in BCP 146 14 [RFC2119] [RFC8174] when, and only when, they appear in all 147 capitals, as shown here. 149 Readers are expected to be familiar with the terms and concepts used 150 in EAP [RFC3748], EAP-TLS [RFC5216], and TLS [RFC8446]. In 151 particular, this document frequently uses the following terms as they 152 have been defined in [RFC5216]: 154 Authenticator The entity initiating EAP authentication. Typically 155 implemented as part of a network switch or a wireless access 156 point. 158 EAP peer The entity that responds to the authenticator. In 159 [IEEE-802.1X], this entity is known as the supplicant. In EAP- 160 TLS, the EAP peer implements the TLS client role. 162 EAP server The entity that terminates the EAP authentication method 163 with the peer. In the case where no backend authentication 164 server is used, the EAP server is part of the authenticator. 165 In the case where the authenticator operates in pass-through 166 mode, the EAP server is located on the backend authentication 167 server. In EAP-TLS, the EAP server implements the TLS server 168 role. 170 The document additionally uses the terms trust anchor and 171 certification path defined in [RFC5280]. 173 3. Experience with Deployments 175 As stated earlier, the EAP fragment size in typical deployments is 176 just 1020 - 1500 octets. Certificate sizes can however be large for 177 a number of reasons: 179 o Long Subject Alternative Name field. 181 o Long Public Key and Signature fields. 183 o Can contain multiple object identifiers (OID) that indicate the 184 permitted uses of the certificate as noted in Section 5.3 of 185 [RFC5216]. Most implementations verify the presence of these OIDs 186 for successful authentication. 188 o Multiple user groups in the certificate. 190 A certificate chain (called a certification path in [RFC5280]) can 191 commonly have 2 - 6 intermediate certificates between the end-entity 192 certificate and the trust anchor. 194 Many access point implementations drop EAP sessions that do not 195 complete within 50 round-trips. This means that if the chain is 196 larger than ~ 60 kbytes, EAP-TLS authentication cannot complete 197 successfully in most deployments. 199 4. Handling of Large Certificates and Long Certificate Chains 201 This section discusses some possible alternatives for overcoming the 202 challenge of large certificates and long certificate chains in EAP- 203 TLS authentication. Section 4.1 considers recommendations that 204 require an update of the certificates or certificate chains used for 205 EAP-TLS authentication without requiring changes to the existing EAP- 206 TLS code base. It also provides some guidelines that should be 207 followed when issuing certificates for use with EAP-TLS. Section 4.2 208 considers recommendations that rely on updates to the EAP-TLS 209 implementations and can be deployed with existing certificates. 210 Finally, Section 4.3 briefly discusses what could be done to update 211 or reconfigure authenticators when it is infeasible to replace 212 deployed components giving a solution which can be deployed without 213 changes to existing certificates or code. 215 4.1. Updating Certificates and Certificate Chains 217 Many IETF protocols now use elliptic curve cryptography (ECC) 218 [RFC6090] for the underlying cryptographic operations. The use of 219 ECC can reduce the size of certificates and signatures. For example, 220 at a 128-bit security level, the size of public keys with traditional 221 RSA is about 384 bytes, while the size of public keys with ECC is 222 only 32-64 bytes. Similarly, the size of digital signatures with 223 traditional RSA is 384 bytes, while the size is only 64 bytes with 224 elliptic curve digital signature algorithm (ECDSA) and Edwards-curve 225 digital signature algorithm (EdDSA) [RFC8032]. Using certificates 226 that use ECC can reduce the number of messages in EAP-TLS 227 authentication which can alleviate the problem of authenticators 228 dropping an EAP session because of too many round-trips. In the 229 absence of a standard application profile specifying otherwise, TLS 230 1.3 [RFC8446] requires implementations to support ECC. New cipher 231 suites that use ECC are also specified for TLS 1.2 [RFC5289]. Using 232 ECC based cipher suites with existing code can significantly reduce 233 the number of messages in a single EAP session. 235 4.1.1. Guidelines for Certificates 237 The general guideline of keeping the certificate size small by not 238 populating fields with excessive information can help avert the 239 problems of failed EAP-TLS authentication. More specific 240 recommendations for certificates used with EAP-TLS are as follows: 242 o Object Identifiers (OIDs) is an ASN.1 data type that defines 243 unique identifiers for objects. The OID's ASN.1 value, which is a 244 string of integers, is then used to name objects to which they 245 relate. The Distinguished Encoding Rules (DER) length for the 246 first two integers is always one octet and subsequent integers are 247 base 128-encoded in the fewest possible octets. OIDs are used 248 lavishly in X.509 certificates [RFC5280] and while not all can be 249 avoided, e.g., OIDs for extensions or algorithms and their 250 associate parameters, some are well within the certificate 251 issuer's control: 253 * Each naming attribute in a DN (Directory Name) has one. DNs 254 used in the issuer and subject fields as well as numerous 255 extensions. A shallower naming will be smaller, e.g., C=FI, 256 O=Example, SN=B0A123499EFC as against C=FI, O=Example, 257 OU=Division 1, SOPN=Southern Finland, CN=Coolest IoT Gadget 258 Ever, SN=B0A123499EFC. 260 * Every certificate policy (and qualifier) and any mappings to 261 another policy uses identifiers. Consider carefully what 262 policies apply. 264 o DirectoryString and GeneralName types are used extensively to name 265 things, e.g., the DN naming attribute O= (the organizational 266 naming attribute) DirectoryString includes "Example" for the 267 Example organization and uniformResourceIdentifier can be used to 268 indicate the location of the CRL, e.g., "http://crl.example.com/ 269 sfig2s1-128.crl", in the CRL Distribution Point extension. For 270 these particular examples, each character is a byte. For some 271 non-ASCII character strings in the DN, characters can be multi- 272 byte. Obviously, the names need to be unique, but there is more 273 than one way to accomplish this without long strings. This is 274 especially true if the names are not meant to be meaningful to 275 users. 277 o Extensions are necessary to comply with [RFC5280], but the vast 278 majority are optional. Include only those that are necessary to 279 operate. 281 o As stated earlier, certificate chains of the EAP peer often follow 282 organizational hierarchies. In such cases, information in 283 intermediate certificates (such as postal addresses) do not 284 provide any additional value and they can be shortened (for 285 example: only including the department name instead of the full 286 postal address). 288 4.1.2. Pre-distributing and Omitting CA certificates 290 The TLS Certificate message conveys the sending endpoint's 291 certificate chain. TLS allows endpoints to reduce the size of the 292 Certificate message by omitting certificates that the other endpoint 293 is known to possess. When using TLS 1.3, all certificates that 294 specify a trust anchor known by the other endpoint may be omitted 295 (see Section 4.4.2 of [RFC8446]). When using TLS 1.2 or earlier, 296 only the self-signed certificate that specifies the root certificate 297 authority may be omitted (see Section 7.4.2 of [RFC5246] Therefore, 298 updating TLS implementations to version 1.3 can help to significantly 299 reduce the number of messages exchanged for EAP-TLS authentication. 300 The omitted certificates need to be pre-distributed independently of 301 TLS and the TLS implementations need to be configured to omit these 302 pre-distributed certificates. 304 4.1.3. Using Fewer Intermediate Certificates 306 The EAP peer certificate chain does not have to mirror the 307 organizational hierarchy. For successful EAP-TLS authentication, 308 certificate chains SHOULD NOT contain more than 2-4 intermediate 309 certificates. 311 Administrators responsible for deployments using TLS-based EAP 312 methods can examine the certificate chains and make rough 313 calculations about the number of round trips required for successful 314 authentication. For example, dividing the total size of all the 315 certificates in the peer and server certificate chain (in bytes) by 316 1020 bytes will indicate the minimum number of round trips required. 317 If this number exceeds 50, then, administrators can expect failures 318 with many common authenticator implementations. 320 4.2. Updating TLS and EAP-TLS Code 322 This section discusses how the fragmentation problem can be avoided 323 by updating the underlying TLS or EAP-TLS implementation. Note that 324 in many cases the new feature may already be implemented in the 325 underlying library and simply needs to be taken into use. 327 4.2.1. URLs for Client Certificates 329 [RFC6066] defines the "client_certificate_url" extension which allows 330 TLS clients to send a sequence of Uniform Resource Locators (URLs) 331 instead of the client certificate. URLs can refer to a single 332 certificate or a certificate chain. Using this extension can curtail 333 the amount of fragmentation in EAP deployments thereby allowing EAP 334 sessions to successfully complete. 336 4.2.2. Caching Certificates 338 The TLS Cached Information Extension [RFC7924] specifies an extension 339 where a server can exclude transmission of certificate information 340 cached in an earlier TLS handshake. The client and the server would 341 first execute the full TLS handshake. The client would then cache 342 the certificate provided by the server. When the TLS client later 343 connects to the same TLS server without using session resumption, it 344 can attach the "cached_info" extension to the ClientHello message. 345 This would allow the client to indicate that it has cached the 346 certificate. The client would also include a fingerprint of the 347 server certificate chain. If the server's certificate has not 348 changed, then the server does not need to send its certificate and 349 the corresponding certificate chain again. In case information has 350 changed, which can be seen from the fingerprint provided by the 351 client, the certificate payload is transmitted to the client to allow 352 the client to update the cache. The extension however necessitates a 353 successful full handshake before any caching. This extension can be 354 useful when, for example, a successful authentication between an EAP 355 peer and EAP server has occurred in the home network. If 356 authenticators in a roaming network are stricter at dropping long EAP 357 sessions, an EAP peer can use the Cached Information Extension to 358 reduce the total number of messages. 360 However, if all authenticators drop the EAP session for a given EAP 361 peer and EAP server combination, a successful full handshake is not 362 possible. An option in such a scenario would be to cache validated 363 certificate chains even if the EAP-TLS exchange fails, but this is 364 currently not allowed according to [RFC7924]. 366 4.2.3. Compressing Certificates 368 The TLS working group is also working on an extension for TLS 1.3 369 [I-D.ietf-tls-certificate-compression] that allows compression of 370 certificates and certificate chains during full handshakes. The 371 client can indicate support for compressed server certificates by 372 including this extension in the ClientHello message. Similarly, the 373 server can indicate support for compression of client certificates by 374 including this extension in the CertificateRequest message. While 375 such an extension can alleviate the problem of excessive 376 fragmentation in EAP-TLS, it can only be used with TLS version 1.3 377 and higher. Deployments that rely on older versions of TLS cannot 378 benefit from this extension. 380 4.2.4. Compact TLS 1.3 382 [I-D.ietf-tls-ctls] defines a "compact" version of TLS 1.3 and 383 reduces the message size of the protocol by removing obsolete 384 material and using more efficient encoding. It also defines a 385 compression profile with which either side can define a dictionary of 386 "known certificates". Thus, cTLS can provide another mechanism for 387 EAP-TLS deployments to reduce the size of messages and avoid 388 excessive fragmentation. 390 4.2.5. Suppressing Intermediate Certificates 392 For a client that has all intermediate certificates in the 393 certificate chain, having the server send intermediates in the TLS 394 handshake increases the size of the handshake unnecessarily. The TLS 395 working group is working on an extension for TLS 1.3 396 [I-D.thomson-tls-sic] that allows a TLS client that has access to the 397 complete set of published intermediate certificates to inform servers 398 of this fact so that the server can avoid sending intermediates, 399 reducing the size of the TLS handshake. The mechanism is intended to 400 be complementary with certificate compression. 402 4.2.6. Raw Public Keys 404 [RFC7250] defines a new certificate type and TLS extensions to enable 405 the use of raw public keys for authentication. Raw public keys use 406 only a subset of information found in typical certificates and are 407 therefore much smaller in size. However, raw public keys require an 408 out-of-band mechanism to bind the public key with the entity 409 presenting the key. Using raw public keys will obviously avoid the 410 fragmentation problems resulting from large certificates and long 411 certificate chains. Deployments can consider their use as long as an 412 appropriate out-of-band mechanism for binding public keys with 413 identifiers is in place. 415 4.2.7. New Certificate Types and Compression Algorithms 417 There is ongoing work to specify new certificate types and 418 compression algorithms. For example, 419 [I-D.mattsson-tls-cbor-cert-compress] defines a compression algorithm 420 for certificates that relies on Concise Binary Object Representation 421 (CBOR) [RFC7049]. [I-D.tschofenig-tls-cwt] registers a new TLS 422 Certificate type which would enable TLS implementations to use CBOR 423 Web Tokens (CWTs) [RFC8392] as certificates. While these are early 424 initiatives, future EAP-TLS deployments can consider the use of these 425 new certificate types and compression algorithms to avoid large 426 message sizes. 428 4.3. Updating Authenticators 430 There are several legitimate reasons that authenticators may want to 431 limit the number of round-trips/packets/octets that can be sent. The 432 main reason has been to work around issues where the EAP peer and EAP 433 server end up in an infinite loop ACKing their messages. Another 434 reason is that unlimited communication from an unauthenticated device 435 using EAP could provide a channel for inappropriate bulk data 436 transfer. A third reason is to prevent denial-of-service attacks. 438 Updating the millions of already deployed access points and switches 439 is in many cases not realistic. Vendors may be out of business or do 440 no longer support the products and administrators may have lost the 441 login information to the devices. For practical purposes the EAP 442 infrastructure is ossified for the time being. 444 Vendors making new authenticators should consider increasing the 445 number of round-trips allowed to 100 before denying the EAP 446 authentication to complete. Based on the size of the certificates 447 and certificate chains currently deployed, such an increase would 448 likely ensure that peers and servers can complete EAP-TLS 449 authentication. At the same time, administrators responsible for EAP 450 deployments should ensure that this 100 roundtrip limit is not 451 exceeded in practice. 453 5. IANA Considerations 455 This document includes no request to IANA. 457 6. Security Considerations 459 Updating implementations to TLS version 1.3 allows omitting all 460 certificates with a trust anchor known by the other endpoint. TLS 461 1.3 additionally provides improved security, privacy, and reduced 462 latency for EAP-TLS [I-D.ietf-emu-eap-tls13]. 464 Security considerations when compressing certificates are specified 465 in [I-D.ietf-tls-certificate-compression]. 467 As noted in [I-D.thomson-tls-sic], suppressing intermediate 468 certificates creates an unencrypted signal that might be used to 469 identify which clients believe that they have all intermediates. 470 This might also allow more effective fingerprinting and tracking of 471 clients. 473 7. References 475 7.1. Normative References 477 [I-D.ietf-emu-eap-tls13] 478 Mattsson, J. and M. Sethi, "Using EAP-TLS with TLS 1.3", 479 draft-ietf-emu-eap-tls13-11 (work in progress), October 480 2020. 482 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 483 Requirement Levels", BCP 14, RFC 2119, 484 DOI 10.17487/RFC2119, March 1997, 485 . 487 [RFC3748] Aboba, B., Blunk, L., Vollbrecht, J., Carlson, J., and H. 488 Levkowetz, Ed., "Extensible Authentication Protocol 489 (EAP)", RFC 3748, DOI 10.17487/RFC3748, June 2004, 490 . 492 [RFC4851] Cam-Winget, N., McGrew, D., Salowey, J., and H. Zhou, "The 493 Flexible Authentication via Secure Tunneling Extensible 494 Authentication Protocol Method (EAP-FAST)", RFC 4851, 495 DOI 10.17487/RFC4851, May 2007, 496 . 498 [RFC5216] Simon, D., Aboba, B., and R. Hurst, "The EAP-TLS 499 Authentication Protocol", RFC 5216, DOI 10.17487/RFC5216, 500 March 2008, . 502 [RFC5280] Cooper, D., Santesson, S., Farrell, S., Boeyen, S., 503 Housley, R., and W. Polk, "Internet X.509 Public Key 504 Infrastructure Certificate and Certificate Revocation List 505 (CRL) Profile", RFC 5280, DOI 10.17487/RFC5280, May 2008, 506 . 508 [RFC5281] Funk, P. and S. Blake-Wilson, "Extensible Authentication 509 Protocol Tunneled Transport Layer Security Authenticated 510 Protocol Version 0 (EAP-TTLSv0)", RFC 5281, 511 DOI 10.17487/RFC5281, August 2008, 512 . 514 [RFC7170] Zhou, H., Cam-Winget, N., Salowey, J., and S. Hanna, 515 "Tunnel Extensible Authentication Protocol (TEAP) Version 516 1", RFC 7170, DOI 10.17487/RFC7170, May 2014, 517 . 519 [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 520 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, 521 May 2017, . 523 7.2. Informative References 525 [I-D.ietf-tls-certificate-compression] 526 Ghedini, A. and V. Vasiliev, "TLS Certificate 527 Compression", draft-ietf-tls-certificate-compression-10 528 (work in progress), January 2020. 530 [I-D.ietf-tls-ctls] 531 Rescorla, E., Barnes, R., and H. Tschofenig, "Compact TLS 532 1.3", draft-ietf-tls-ctls-00 (work in progress), April 533 2020. 535 [I-D.mattsson-tls-cbor-cert-compress] 536 Mattsson, J., Selander, G., Raza, S., Hoglund, J., and M. 537 Furuhed, "CBOR Certificate Algorithm for TLS Certificate 538 Compression", draft-mattsson-tls-cbor-cert-compress-00 539 (work in progress), March 2020. 541 [I-D.thomson-tls-sic] 542 Thomson, M., "Suppressing Intermediate Certificates in 543 TLS", draft-thomson-tls-sic-00 (work in progress), March 544 2019. 546 [I-D.tschofenig-tls-cwt] 547 Tschofenig, H. and M. Brossard, "Using CBOR Web Tokens 548 (CWTs) in Transport Layer Security (TLS) and Datagram 549 Transport Layer Security (DTLS)", draft-tschofenig-tls- 550 cwt-02 (work in progress), July 2020. 552 [IEEE-802.1X] 553 Institute of Electrical and Electronics Engineers, "IEEE 554 Standard for Local and metropolitan area networks -- Port- 555 Based Network Access Control", IEEE Standard 802.1X-2010 , 556 February 2010. 558 [RFC2865] Rigney, C., Willens, S., Rubens, A., and W. Simpson, 559 "Remote Authentication Dial In User Service (RADIUS)", 560 RFC 2865, DOI 10.17487/RFC2865, June 2000, 561 . 563 [RFC5246] Dierks, T. and E. Rescorla, "The Transport Layer Security 564 (TLS) Protocol Version 1.2", RFC 5246, 565 DOI 10.17487/RFC5246, August 2008, 566 . 568 [RFC5289] Rescorla, E., "TLS Elliptic Curve Cipher Suites with SHA- 569 256/384 and AES Galois Counter Mode (GCM)", RFC 5289, 570 DOI 10.17487/RFC5289, August 2008, 571 . 573 [RFC6066] Eastlake 3rd, D., "Transport Layer Security (TLS) 574 Extensions: Extension Definitions", RFC 6066, 575 DOI 10.17487/RFC6066, January 2011, 576 . 578 [RFC6090] McGrew, D., Igoe, K., and M. Salter, "Fundamental Elliptic 579 Curve Cryptography Algorithms", RFC 6090, 580 DOI 10.17487/RFC6090, February 2011, 581 . 583 [RFC7049] Bormann, C. and P. Hoffman, "Concise Binary Object 584 Representation (CBOR)", RFC 7049, DOI 10.17487/RFC7049, 585 October 2013, . 587 [RFC7250] Wouters, P., Ed., Tschofenig, H., Ed., Gilmore, J., 588 Weiler, S., and T. Kivinen, "Using Raw Public Keys in 589 Transport Layer Security (TLS) and Datagram Transport 590 Layer Security (DTLS)", RFC 7250, DOI 10.17487/RFC7250, 591 June 2014, . 593 [RFC7924] Santesson, S. and H. Tschofenig, "Transport Layer Security 594 (TLS) Cached Information Extension", RFC 7924, 595 DOI 10.17487/RFC7924, July 2016, 596 . 598 [RFC8032] Josefsson, S. and I. Liusvaara, "Edwards-Curve Digital 599 Signature Algorithm (EdDSA)", RFC 8032, 600 DOI 10.17487/RFC8032, January 2017, 601 . 603 [RFC8392] Jones, M., Wahlstroem, E., Erdtman, S., and H. Tschofenig, 604 "CBOR Web Token (CWT)", RFC 8392, DOI 10.17487/RFC8392, 605 May 2018, . 607 [RFC8446] Rescorla, E., "The Transport Layer Security (TLS) Protocol 608 Version 1.3", RFC 8446, DOI 10.17487/RFC8446, August 2018, 609 . 611 Acknowledgements 613 This draft is a result of several useful discussions with Alan DeKok, 614 Bernard Aboba, Jari Arkko, Jouni Malinen, Darshak Thakore, and Hannes 615 Tschofening. 617 Authors' Addresses 619 Mohit Sethi 620 Ericsson 621 Jorvas 02420 622 Finland 624 Email: mohit@piuha.net 626 John Mattsson 627 Ericsson 628 Kista 629 Sweden 631 Email: john.mattsson@ericsson.com 633 Sean Turner 634 sn3rd 636 Email: sean@sn3rd.com