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(The document does seem to have the reference to RFC 2119 which the ID-Checklist requires). -- The document date (June 15, 2016) is 2870 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: 'SP800-57' is mentioned on line 555, but not defined -- Obsolete informational reference (is this intentional?): RFC 5751 (Obsoleted by RFC 8551) Summary: 0 errors (**), 0 flaws (~~), 3 warnings (==), 2 comments (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 Network Working Group R. Bush 3 Internet-Draft IIJ Lab / Dragon Research Lab 4 Intended status: Standards Track S. Turner 5 Expires: December 17, 2016 IECA, Inc. 6 K. Patel 7 Cisco Systems 8 June 15, 2016 10 Router Keying for BGPsec 11 draft-ietf-sidr-rtr-keying-11 13 Abstract 15 BGPsec-speaking routers are provisioned with private keys in order to 16 sign BGPsec announcements. The corresponding public keys are 17 published in the global Resource Public Key Infrastructure, enabling 18 verification of BGPsec messages. This document describes two methods 19 of generating the public-private key-pairs: router-driven and 20 operator-driven. 22 Requirements Language 24 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 25 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" are to 26 be interpreted as described in RFC 2119 [RFC2119] only when they 27 appear in all upper case. They may also appear in lower or mixed 28 case as English words, without normative meaning. 30 Status of This Memo 32 This Internet-Draft is submitted in full conformance with the 33 provisions of BCP 78 and BCP 79. 35 Internet-Drafts are working documents of the Internet Engineering 36 Task Force (IETF). Note that other groups may also distribute 37 working documents as Internet-Drafts. The list of current Internet- 38 Drafts is at http://datatracker.ietf.org/drafts/current/. 40 Internet-Drafts are draft documents valid for a maximum of six months 41 and may be updated, replaced, or obsoleted by other documents at any 42 time. It is inappropriate to use Internet-Drafts as reference 43 material or to cite them other than as "work in progress." 45 This Internet-Draft will expire on May 5, 2016. 47 Copyright Notice 49 Copyright (c) 2016 IETF Trust and the persons identified as the 50 document authors. All rights reserved. 52 This document is subject to BCP 78 and the IETF Trust's Legal 53 Provisions Relating to IETF Documents 54 (http://trustee.ietf.org/license-info) in effect on the date of 55 publication of this document. Please review these documents 56 carefully, as they describe your rights and restrictions with respect 57 to this document. Code Components extracted from this document must 58 include Simplified BSD License text as described in Section 4.e of 59 the Trust Legal Provisions and are provided without warranty as 60 described in the Simplified BSD License. 62 Table of Contents 64 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 65 2. Management / Router Communication . . . . . . . . . . . . . . 3 66 3. Exchanging Certificates . . . . . . . . . . . . . . . . . . . 4 67 4. Set-Up . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 68 5. PKCS#10 Generation . . . . . . . . . . . . . . . . . . . . . 4 69 5.1. Router-Generated Keys . . . . . . . . . . . . . . . . . . 4 70 5.2. Operator-Generated Keys . . . . . . . . . . . . . . . . . 5 71 6. Installing Signed Keys . . . . . . . . . . . . . . . . . . . 5 72 7. Key Management . . . . . . . . . . . . . . . . . . . . . . . 6 73 7.1. Key Validity . . . . . . . . . . . . . . . . . . . . . . 7 74 7.2. Key Roll-Over . . . . . . . . . . . . . . . . . . . . . . 7 75 7.3. Key Revocation . . . . . . . . . . . . . . . . . . . . . 8 76 7.4. Router Replacement . . . . . . . . . . . . . . . . . . . 8 77 8. Security Considerations . . . . . . . . . . . . . . . . . . . 9 78 9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 10 79 10. References . . . . . . . . . . . . . . . . . . . . . . . . . 10 80 10.1. Normative References . . . . . . . . . . . . . . . . . . 10 81 10.2. Informative References . . . . . . . . . . . . . . . . . 11 82 Appendix A. Management/Router Channel Security . . . . . . . . . 12 83 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 13 85 1. Introduction 87 BGPsec-speaking routers are provisioned with private keys, which 88 allow them to digitally sign BGPsec announcements. To verify the 89 signature, the public key, in the form of a certificate 90 [I-D.ietf-sidr-bgpsec-pki-profiles], is published in the Resource 91 Public Key Infrastructure (RPKI). This document describes 92 provisioning of BGPsec-speaking routers with the appropriate public- 93 private key-pairs. There are two sub-methods, router-driven and 94 operator-driven. 96 These two sub-methods differ in where the keys are generated: on the 97 router in the router-driven method, and elsewhere in the operator- 98 driven method. Routers are required to support at least one of the 99 methods in order to work in various deployment environments. Some 100 routers may not allow the private key to be off-loaded while others 101 may. While off-loading private keys would ease swapping of routing 102 engines, exposure of private keys is a well known security risk. 104 In the operator-driven method, the operator generates the private/ 105 public key-pair and sends it to the router, perhaps in a PKCS#8 106 package [RFC5958]. 108 In the router-driven method, the router generates its own public/ 109 private key-pair, uses the private key to sign a PKCS#10 110 certification request [I-D.ietf-sidr-bgpsec-pki-profiles], which 111 includes the public key), and returns the certification request to 112 the operator to be forwarded to the RPKI Certification Authority 113 (CA). The CA returns a PKCS#7, which includes the certified public 114 key in the form of a certificate, to the operator for loading into 115 the router; and the CA also publishes the certificate in the RPKI. 117 The router-driven model mirrors the model used by traditional PKI 118 subscribers; the private key never leaves trusted storage (e.g., 119 Hardware Security Module). This is by design and supports classic 120 PKI Certification Policies for (often human) subscribers which 121 require the private key only ever be controlled by the subscriber to 122 ensure that no one can impersonate the subscriber. For non-humans, 123 this model does not always work. For example, when an operator wants 124 to support hot-swappable routers the same private key needs to be 125 installed in the soon-to-be online router that was used by the the 126 soon-to-be offline router. This motivated the operator-driven model. 128 The remainder of this document describes how operators can use the 129 two methods to provision new and existing routers. 131 Useful References: [I-D.ietf-sidr-bgpsec-overview] gives an overview 132 of the BGPsec protocol, [I-D.ietf-sidr-bgpsec-protocol] gives the 133 gritty details, [I-D.ietf-sidr-bgpsec-pki-profiles] specifies the 134 format for the PKCS #10 request, and [I-D.ietf-sidr-bgpsec-algs] 135 specifies the algorithms used to generate the signature. 137 2. Management / Router Communication 139 Operators are free to use either the router-driven or operator-driven 140 method as supported by the platform. Regardless of the method 141 chosen, operators first establish a secure communication channel 142 between the management system and the router. How this channel is 143 established is router-specific and is beyond scope of this document. 145 Though other configuration mechanisms might be used, e.g. NetConf 146 (see [RFC6470]); for simplicity, in this document, the communication 147 channel between the management platform and the router is assumed to 148 be an SSH-protected CLI. See Appendix A for security considerations 149 for this channel. 151 3. Exchanging Certificates 153 The operator management station can exchange certificate requests and 154 certificates with routers and with the RPKI CA infrastructure using 155 the application/pkcs10 media type [RFC5967] and application/ 156 pkcs7-mime [RFC5751], respectively, and may use FTP or HTTP per 157 [RFC2585], or the Enrollment over Secure Transport [RFC7030]. 159 4. Set-Up 161 To start, the operator uses the communication channel to install the 162 appropriate RPKI Trust Anchor' Certificate (TA Cert) in the router. 163 This will later enable the router to validate the router certificate 164 returned in the PKCS#7. 166 The operator also configures the Autonomous System (AS) number to be 167 used in the generated router certificate. This may be the sole AS 168 configured on the router, or an operator choice if the router is 169 configured with multiple ASs. 171 The operator configures or extracts from the router the BGP RouterID 172 to be used in the generated certificate. In the case where the 173 operator has chosen not to use unique per-router certificates, a 174 RouterID of 0 may be used. 176 5. PKCS#10 Generation 178 The private key, and hence the PKCS#10 request may be generated by 179 the router or by the operator. 181 5.1. Router-Generated Keys 183 In the router-generated method, once the protected session is 184 established and the initial Set-Up (Section 4) performed, the 185 operator issues a command or commands for the router to generate the 186 public/private key pair, to generate the PKCS#10 request, and to sign 187 the PKCS#10 with the private key. Once generated, the PKCS#10 is 188 returned to the operator over the protected channel. 190 If a router was to communicate directly with a CA to have the CA 191 certify the PKCS#10, there would be no way for the CA to authenticate 192 the router. As the operator knows the authenticity of the router, 193 the operator must mediate the communication with the CA. 195 The operator adds the chosen AS number and the RouterID to send to 196 the RPKI CA for the CA to certify. 198 5.2. Operator-Generated Keys 200 In the operator-generated method, the operator generates the public/ 201 private key pair on a management station and installs the private key 202 into the router over the protected channel. Beware that experience 203 has shown that copy and paste from a management station to a router 204 can be unreliable for long texts. 206 Alternatively, the private key may be encapsulated in a PKCS #8 207 [RFC5958], the PKCS#8 is further encapsulated in Cryptographic 208 Message Syntax (CMS) SignedData [RFC5652], and signed by the AS's End 209 Entity (EE) certificate. 211 The router SHOULD verify the signature of the encapsulated PKCS#8 to 212 ensure the returned private key did in fact come from the operator, 213 but this requires that the operator also provision via the CLI or 214 include in the SignedData the RPKI CA certificate and relevant AS's 215 EE certificate(s). The router should inform the operator whether or 216 not the signature validates to a trust anchor; this notification 217 mechanism is out of scope. 219 The operator then creates and signs the PKCS#10 with the private key, 220 and adds the chosen AS number and RouterID to be sent to the RPKI CA 221 for the CA to certify. 223 6. Installing Signed Keys 225 The operator uses RPKI management tools to communicate with the 226 global RPKI system to have the appropriate CA validate the PKCS#10 227 request, sign the key in the PKCS#10 and generated PKCS#7 response, 228 as well as publishing the certificate in the Global RPKI. External 229 network connectivity may be needed if the certificate is to be 230 published in the Global RPKI. 232 After the CA certifies the key, it does two things: 234 1. Publishes the certificate in the Global RPKI. The CA must have 235 connectivity to the relevant publication point, which in turn 236 must have external network connectivity as it is part of the 237 Global RPKI. 239 2. Returns the certificate to the operator's management station, 240 packaged in a PKCS#7, using the corresponding method by which it 241 received the certificate request. It SHOULD include the 242 certificate chain below the TA Certificate so that the router can 243 validate the router certificate. 245 In the operator-generated method, the operator SHOULD extract the 246 certificate from the PKCS#7, and verify that the private key it holds 247 corresponds to the returned public key. 249 In the operator-generated method, the operator has already installed 250 the private key in the router (see Section 5.2). 252 The operator provisions the PKCS#7 into the router over the secure 253 channel. 255 The router SHOULD extract the certificate from the PKCS#7 and verify 256 that the private key corresponds to the returned public key. The 257 router SHOULD inform the operator whether it successfully received 258 the certificate and whether or not the keys correspond; the mechanism 259 is out of scope. 261 The router SHOULD also verify that the returned certificate validates 262 back to the installed TA Certificate, i.e., the entire chain from the 263 installed TA Certificate through subordinate CAs to the BGPsec 264 certificate validate. To perform this verification the CA 265 certificate chain needs to be returned along with the router's 266 certificate in the PKCS#7. The router SHOULD inform the operator 267 whether or not the signature validates to a trust anchor; this 268 notification mechanism is out of scope. 270 Note: The signature on the PKCS#8 and Certificate need not be made by 271 the same entity. Signing the PKCS#8, permits more advanced 272 configurations where the entity that generates the keys is not the 273 direct CA. 275 Even if the operator cannot extract the private key from the router, 276 this signature still provides a linkage between a private key and a 277 router. That is the server can verify the proof of possession (POP), 278 as required by [RFC6484]. 280 7. Key Management 282 An operator's responsibilities do not end after key generation, key 283 provisioning, certificate issuance, and certificate distribution. 284 They persist for as long as the operator wishes to operate the 285 BGPsec-speaking router. 287 7.1. Key Validity 289 It is critical that a BGPsec speaking router ensures that it is 290 signing with a valid certificate at all times. To this end, the 291 operator needs to ensure the router always has a non-expired 292 certificate. I.e. the key used to sign BGPsec announcements always 293 has an associated certificate whose expiry time is after the current 294 time. 296 Ensuring this is not terribly difficult but requires that either: 298 1. The router has a mechanism to notify the operator that the 299 certificate has an impending expiration, and/or 301 2. The operator notes the expiry time of the certificate and uses a 302 calendaring program to remind them of the expiry time, and/or 304 3. The RPKI CA warns the operator of pending expiration, and/or 306 4. Use some other kind of automated process to search for and track 307 the expiry times of router certificates. 309 It is advisable that expiration warnings happen well in advance of 310 the actual expiry time. 312 Regardless of the technique used to track router certificate expiry 313 times, it is advisable to notify additional operators in the same 314 organization as the expiry time approaches thereby ensuring that the 315 forgetfulness of one operator does not affect the entire 316 organization. 318 Depending on inter-operator relationship, it may be helpful to notify 319 a peer operator that one or more of their certificates are about to 320 expire. 322 7.2. Key Roll-Over 324 Routers that support multiple private keys also greatly increase the 325 chance that routers can continuously speak BGPsec because the new 326 private key and certificate can be obtained and distributed prior to 327 expiration of the operational key. Obviously, the router needs to 328 know when to start using the new key. Once the new key is being 329 used, having the already distributed certificate ensures continuous 330 operation. 332 Whether the certificate is re-keyed (i.e., different key in the 333 certificate with a new expiry time) or renewed (i.e., the same key in 334 the certificate with a new expiry time) depends on the key's lifetime 335 and operational use. Arguably, re-keying the router's BGPsec 336 certificate every time the certificate expires is more secure than 337 renewal because it limits the private key's exposure. However, if 338 the key is not compromised the certificate could be renewed as many 339 times as allowed by the operator's security policy. Routers that 340 support only one key can use renewal to ensure continuous operation, 341 assuming the certificate is renewed and distributed well in advance 342 of the operational certificate's expiry time. 344 7.3. Key Revocation 346 Certain unfortunate circumstances may occur causing a need to revoke 347 a router's BGPsec certificate. When this occurs, the operator needs 348 to use the RPKI CA system to revoke the certificate by placing the 349 router's BGPsec certificate on the Certificate Revocation List (CRL) 350 as well as re-keying the router's certificate. 352 When an active router key is to be revoked, the process of requesting 353 the CA to revoke, the process of the CA actually revoking the 354 router's certificate, and then the process of re-keying/renewing the 355 router's certificate, (possibly distributing a new key and 356 certificate to the router), and distributing the status takes time 357 during which the operator must decide how they wish to maintain 358 continuity of operations, with or without the compromised private 359 key, or whether they wish to bring the router offline to address the 360 compromise. 362 Keeping the router operational and BGPsec-speaking is the ideal goal, 363 but if operational practices do not allow this then reconfiguring the 364 router to disabling BGPsec is likely preferred to bringing the router 365 offline. 367 Routers which support more than one private key, where one is 368 operational and other(s) are soon-to-be-operational, facilitate 369 revocation events because the operator can configure the router to 370 make a soon-to-be-operational key operational, request revocation of 371 the compromised key, and then make a next generation soon-to-be- 372 operational key, all hopefully without needing to take offline or 373 reboot the router. For routers which support only one operational 374 key, the operators should create or install the new private key, and 375 then request revocation of the compromised private key. 377 7.4. Router Replacement 379 Currently routers often generate private keys for uses such as SSH, 380 and the private keys may not be seen or off-loaded from the router. 381 While this is good security, it creates difficulties when a routing 382 engine or whole router must be replaced in the field and all software 383 which accesses the router must be updated with the new keys. Also, 384 any network based initial contact with a new routing engine requires 385 trust in the public key presented on first contact. 387 To allow operators to quickly replace routers without requiring 388 update and distribution of the corresponding public keys in the RPKI, 389 routers SHOULD allow the private BGPsec key to be off-loaded via a 390 protected session, e.g. SSH, NetConf (see [RFC6470]), SNMP, etc. 391 This lets the operator upload the old private key via the mechanism 392 used for operator-generated keys, see Section 5.2. 394 8. Security Considerations 396 The router's manual will describe whether the router supports one, 397 the other, or both of the key generation options discussed in the 398 earlier sections of this draft as well as other important security- 399 related information (e.g., how to SSH to the router). After 400 familiarizing one's self with the capabilities of the router, 401 operators are encouraged to ensure that the router is patched with 402 the latest software updates available from the manufacturer. 404 This document defines no protocols so in some sense introduces no new 405 security considerations. However, it relies on many others and the 406 security considerations in the referenced documents should be 407 consulted; notably, those document listed in Section 1 should be 408 consulted first. PKI-relying protocols, of which BGPsec is one, have 409 many issues to consider so many in fact entire books have been 410 written to address them; so listing all PKI-related security 411 considerations is neither useful nor helpful; regardless, some boot- 412 strapping-related issues are listed here that are worth repeating: 414 Public-Private key pair generation: Mistakes here are for all 415 practical purposes catastrophic because PKIs rely on the pairing 416 of a difficult to generate public-private key pair with a signer; 417 all key pairs MUST be generated from a good source of non- 418 deterministic random input [RFC4086]. 420 Private key protection at rest: Mistakes here are for all practical 421 purposes catastrophic because disclosure of the private key allows 422 another entity to masquerade as (i.e., impersonate) the signer; 423 all private keys MUST be protected when at rest in a secure 424 fashion. Obviously, how each router protects private keys is 425 implementation specific. Likewise, the local storage format for 426 the private key is just that, a local matter. 428 Private key protection in transit: Mistakes here are for all 429 practical purposes catastrophic because disclosure of the private 430 key allows another entity to masquerade as (i.e., impersonate) the 431 signer; transport security is therefore strongly RECOMMENDED. The 432 level of security provided by the transport layer's security 433 mechanism SHOULD be commensurate with the strength of the BGPsec 434 key; there's no point in spending time and energy to generate an 435 excellent public-private key pair and then transmit the private 436 key in the clear or with a known-to-be-broken algorithm, as it 437 just undermines trust that the private key has been kept private. 438 Additionally, operators SHOULD ensure the transport security 439 mechanism is up to date, in order to addresses all known 440 implementation bugs. 442 SSH key management is known, in some cases, to be lax 443 [I-D.ylonen-sshkeybcp]; employees that no longer need access to 444 routers SHOULD be removed the router to ensure only those authorized 445 have access to a router. 447 Though the CA's certificate is installed on the router and used to 448 verify that the returned certificate is in fact signed by the CA, the 449 revocation status of the CA's certificate is rarely checked as the 450 router may not have global connectivity or CRL-aware software. The 451 operator MUST ensure that installed CA certificate is valid. 453 9. IANA Considerations 455 This document has no IANA Considerations. 457 10. References 459 10.1. Normative References 461 [I-D.ietf-sidr-bgpsec-algs] 462 Turner, S., "BGP Algorithms, Key Formats, & Signature 463 Formats", draft-ietf-sidr-bgpsec-algs (work in 464 progress), March 2013. 466 [I-D.ietf-sidr-bgpsec-pki-profiles] 467 Reynolds, M., Turner, S., and S. Kent, "A Profile for 468 BGPSEC Router Certificates, Certificate Revocation Lists, 469 and Certification Requests", draft-ietf-sidr-bgpsec-pki- 470 profiles (work in progress), October 2012. 472 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 473 Requirement Levels", BCP 14, RFC 2119, March 1997. 475 [RFC4086] Eastlake, D., Schiller, J., and S. Crocker, "Randomness 476 Requirements for Security", BCP 106, RFC 4086, June 2005. 478 [RFC4253] Ylonen, T. and C. Lonvick, "The Secure Shell (SSH) 479 Transport Layer Protocol", RFC 4253, January 2006. 481 [RFC5652] Housley, R., "Cryptographic Message Syntax (CMS)", 482 RFC 5652, September 2009. 484 [RFC5958] Turner, S., "Asymmetric Key Packages", RFC 5958, August 485 2010. 487 10.2. Informative References 489 [I-D.ietf-sidr-bgpsec-overview] 490 Lepinski, M. and S. Turner, "An Overview of BGPSEC", 491 draft-ietf-sidr-bgpsec-overview (work in progress), May 492 2012. 494 [I-D.ietf-sidr-bgpsec-protocol] 495 Lepinski, M., "BGPSEC Protocol Specification", draft-ietf- 496 sidr-bgpsec-protocol (work in progress), February 2013. 498 [I-D.ylonen-sshkeybcp] 499 Ylonen, T. and G. Kent, "Managing SSH Keys for Automated 500 Access - Current Recommended Practice", draft-ylonen- 501 sshkeybcp (work in progress), April 2013. 503 [RFC2585] Housley, R. and P. Hoffman, "Internet X.509 Public Key 504 Infrastructure Operational Protocols: FTP and HTTP", 505 RFC 2585, May 1999. 507 [RFC3766] Orman, H. and P. Hoffman, "Determining Strengths For 508 Public Keys Used For Exchanging Symmetric Keys", BCP 86, 509 RFC 3766, April 2004. 511 [RFC5480] Turner, S., Brown, D., Yiu, K., Housley, R., and T. Polk, 512 "Elliptic Curve Cryptography Subject Public Key 513 Information", RFC 5480, March 2009. 515 [RFC5647] Igoe, K. and J. Solinas, "AES Galois Counter Mode for the 516 Secure Shell Transport Layer Protocol", RFC 5647, August 517 2009. 519 [RFC5656] Stebila, D. and J. Green, "Elliptic Curve Algorithm 520 Integration in the Secure Shell Transport Layer", 521 RFC 5656, December 2009. 523 [RFC5751] Ramsdell, B. and S. Turner, "Secure/Multipurpose Internet 524 Mail Extensions (S/MIME) Version 3.2 Message 525 Specification", RFC 5751, January 2010. 527 [RFC5967] Turner, S., "The application/pkcs10 Media Type", RFC 5967, 528 August 2010. 530 [RFC6187] Igoe, K. and D. Stebila, "X.509v3 Certificates for Secure 531 Shell Authentication", RFC 6187, March 2011. 533 [RFC6470] Bierman, A., "Network Configuration Protocol (NETCONF) 534 Base Notifications", RFC 6470, February 2012. 536 [RFC6484] Kent, S., Kong, D., Seo, K., and R. Watro, "Certificate 537 Policy (CP) for the Resource Public Key Infrastructure 538 (RPKI)", BCP 173, RFC 6484, February 2012. 540 [RFC6668] Bider, D. and M. Baushke, "SHA-2 Data Integrity 541 Verification for the Secure Shell (SSH) Transport Layer 542 Protocol", RFC 6668, July 2012. 544 [RFC7030] Pritikin, M., Ed., Yee, P., Ed., and D. Harkins, Ed., 545 "Enrollment over Secure Transport", RFC 7030, 546 DOI 10.17487/RFC7030, October 2013, 547 . 549 Appendix A. Management/Router Channel Security 551 Encryption, integrity, authentication, and key exchange algorithms 552 used by the secure communication channel SHOULD be of equal or 553 greater strength than the BGPsec keys they protect, which for the 554 algorithm specified in [I-D.ietf-sidr-bgpsec-algs] is 128-bit; see 555 [RFC5480] and by reference [SP800-57] for information about this 556 strength claim as well as [RFC3766] for "how to determine the length 557 of an asymmetric key as a function of a symmetric key strength 558 requirement." In other words, for the encryption algorithm, do not 559 use export grade crypto (40-56 bits of security), do not use Triple 560 DES (112 bits of security). Suggested minimum algorithms would be 561 AES-128: aes128-cbc [RFC4253] and AEAD_AES_128_GCM [RFC5647] for 562 encryption, hmac-sha2-256 [RFC6668] or AESAD_AES_128_GCM [RFC5647] 563 for integrity, ecdsa-sha2-nistp256 [RFC5656] for authentication, and 564 ecdh-sha2-nistp256 [RFC5656] for key exchange. 566 Some routers support the use of public key certificates and SSH. The 567 certificates used for the SSH session are different than the 568 certificates used for BGPsec. The certificates used with SSH should 569 also enable a level of security commensurate with BGPsec keys; 570 x509v3-ecdsa-sha2-nistp256 [RFC6187] could be used for 571 authentication. 573 Authors' Addresses 575 Randy Bush 576 IIJ / Dragon Research Labs 577 5147 Crystal Springs 578 Bainbridge Island, Washington 98110 579 US 581 Email: randy@psg.com 583 Sean Turner 584 IECA, Inc. 585 3057 Nutley Street, Suite 106 586 Fairfax, Virginia 22031 587 US 589 Email: sean@sn3rd.com 591 Keyur Patel 592 Cisco Systems 593 170 W. Tasman Drive 594 San Jose, CA 95134 595 USA 597 Email: keyupate@cisco.com