[Docs] [txt|pdf] [Tracker] [WG] [Email] [Diff1] [Diff2] [Nits]

Versions: (draft-yossigi-rpkimaxlen) 00 01 02

Network Working Group                                           Y. Gilad
Internet-Draft                                               S. Goldberg
Intended status: Best Current Practice                 Boston University
Expires: October 26, 2019                                      K. Sriram
                                                                USA NIST
                                                             J. Snijders
                                                                     NTT
                                                             B. Maddison
                                               Workonline Communications
                                                          April 24, 2019


                    The Use of Maxlength in the RPKI
                    draft-ietf-sidrops-rpkimaxlen-02

Abstract

   This document recommends ways to reduce forged-origin attack surface
   by prudently limiting the address space that is included in Route
   Origin Authorizations (ROAs).  One recommendation is to avoid using
   the maxLength attribute in ROAs except in some specific cases.  The
   recommendations complement and extend those in RFC 7115.  The
   document also discusses creation of ROAs for facilitating Distributed
   Denial of Service (DDoS) mitigation services.  Considerations related
   to ROAs and origin validation for the case of destination-based
   Remote Triggered Black Hole (RTBH) filtering are also highlighted.

Status of This Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at https://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on October 26, 2019.








Gilad, et al.           Expires October 26, 2019                [Page 1]


Internet-Draft               RPKI maxLength                   April 2019


Copyright Notice

   Copyright (c) 2019 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (https://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
   carefully, as they describe your rights and restrictions with respect
   to this document.  Code Components extracted from this document must
   include Simplified BSD License text as described in Section 4.e of
   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
     1.1.  Requirements  . . . . . . . . . . . . . . . . . . . . . .   3
   2.  Suggested Reading . . . . . . . . . . . . . . . . . . . . . .   4
   3.  Forged-Origin Subprefix Hijack  . . . . . . . . . . . . . . .   4
   4.  Measurements of Today's RPKI  . . . . . . . . . . . . . . . .   6
   5.  Recommendations about Minimal ROAs and Maxlength  . . . . . .   6
     5.1.  Creation of ROAs Facilitating DDoS Mitigation Service . .   7
   6.  ROAs and Origin Validation for RTBH Filtering Scenario  . . .   9
   7.  Acknowledgments . . . . . . . . . . . . . . . . . . . . . . .   9
   8.  References  . . . . . . . . . . . . . . . . . . . . . . . . .   9
     8.1.  Normative References  . . . . . . . . . . . . . . . . . .   9
     8.2.  Informative References  . . . . . . . . . . . . . . . . .  10
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  11

1.  Introduction

   The RPKI [RFC6480] uses Route Origin Authorizations (ROAs) to create
   a cryptographically verifiable mapping from an IP prefix to a set of
   autonomous systems (ASes) that are authorized to originate this
   prefix.  Each ROA contains a set of IP prefixes, and an AS number of
   an AS authorized originate all the IP prefixes in the set [RFC6482].
   The ROA is cryptographically signed by the party that holds a
   certificate for the set of IP prefixes.

   The ROA format also supports a maxLength attribute.  According to
   [RFC6482], "When present, the maxLength specifies the maximum length
   of the IP address prefix that the AS is authorized to advertise."
   Thus, rather than requiring the ROA to list each prefix the AS is
   authorized to originate, the maxLength attribute provides a shorthand
   that authorizes an AS to originate a set of IP prefixes.




Gilad, et al.           Expires October 26, 2019                [Page 2]


Internet-Draft               RPKI maxLength                   April 2019


   However, measurements of current RPKI deployments have found that use
   of the maxLength in ROAs tends to lead to security problems.
   Specifically, as of June 2017, 84% of the prefixes specified in ROAs
   that use the maxLength attribute, are vulnerable to a forged-origin
   subprefix hijack [HARMFUL].  The forged-origin prefix or subprefix
   hijack involves inserting the legitimate AS (as specified in the ROA)
   as the origin AS, and can be launched against any IP prefix/subprefix
   that has a ROA.  Consider a prefix/subprefix that has a ROA but is
   unused, i.e., not announced in BGP by a legitimate AS.  A forged-
   origin hijack involving such a prefix/subprefix can propagate widely
   throughout the Internet.  On the other hand, if the prefix/subprefix
   were announced by the legitimate AS, then the propagation of the
   forged-origin hijack is somewhat limited because of its increased
   path length relative to the legitimate announcement.  Of course,
   forged-origin hijacks are harmful in both cases but the extent of
   harm is greater for unannounced prefixes.

   For this reason, this document recommends that, whenever possible,
   operators SHOULD use "minimal ROAs" that include only those IP
   prefixes that are actually originated in BGP, and no other prefixes.
   Further, it recommends ways to reduce forged-origin attack surface by
   prudently limiting the address space that is included in Route Origin
   Authorizations (ROAs).  One recommendation is to avoid using the
   maxLength attribute in ROAs except in some specific cases.  The
   recommendations complement and extend those in RFC 7115.  The
   document also discusses creation of ROAs for facilitating Distributed
   Denial of Service (DDoS) mitigation services.  Considerations related
   to ROAs and origin validation for the case of destination-based
   Remote Triggered Black Hole (RTBH) filtering are also highlighted.

   One ideal place to implement the ROA related recommendations is in
   the user interfaces for configuring ROAs.  Thus, this document
   further recommends that designers and/or providers of such user
   interfaces SHOULD provide warnings to draw the user's attention to
   the risks of using the maxLength attribute.

   Best current practices described in this document require no changes
   to the RPKI specification and will not increase the number of signed
   ROAs in the RPKI, because ROAs already support lists of IP prefixes
   [RFC6482].

1.1.  Requirements

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in [RFC2119].





Gilad, et al.           Expires October 26, 2019                [Page 3]


Internet-Draft               RPKI maxLength                   April 2019


2.  Suggested Reading

   It is assumed that the reader understands BGP [RFC4271], RPKI
   [RFC6480], Route Origin Authorizations (ROAs) [RFC6482], RPKI-based
   Prefix Validation [RFC6811], and BGPsec [RFC8205].

3.  Forged-Origin Subprefix Hijack

   A detailed description and discussion of forged-origin subprefix
   hijack are presented here, especially considering the case when the
   subprefix is not announced in BGP.  The forged-origin subprefix
   hijack is relevant to a scenario in which (1) the RPKI [RFC6480] is
   deployed, and (2) routers use RPKI origin validation to drop invalid
   routes [RFC6811], but (3) BGPsec [RFC8205] (or any similar method to
   validate the truthfulness of the BGP AS_PATH attribute) is not
   deployed.

   We describe the forged-origin subprefix hijack [RFC7115] [GCHSS]
   using a running example.

   Consider the IP prefix 168.122.0.0/16 which is allocated to an
   organization that also operates AS 64496.  In BGP, AS 64496
   originates the IP prefix 168.122.0.0/16 as well as its subprefix
   168.122.225.0/24.  Therefore, the RPKI should contain a ROA
   authorizing AS 64496 to originate these two IP prefixes.  That is,
   the ROA should be

      ROA:(168.122.0.0/16,168.122.225.0/24, AS 64496)

   This ROA is "minimal" because it includes only those IP prefixes that
   AS 64496 originates in BGP, but no other IP prefixes [RFC6907].

   Now suppose an attacking AS 64511 originates a BGP announcement for a
   subprefix 168.122.0.0/24.  This is a standard "subprefix hijack".

   In the absence of the minimal ROA above, AS 64511 could intercept
   traffic for the addresses in 168.122.0.0/24.  This is because routers
   perform a longest-prefix match when deciding where to forward IP
   packets, and 168.122.0.0/24 originated by AS 64511 is a longer prefix
   than 168.122.0.0/16 originated by AS 64496.

   However, the minimal ROA renders AS 64511's BGP announcement invalid,
   because (1) this ROA "covers" the attacker's announcement (since
   168.122.0.0/24 is a subprefix of 168.122.0.0/16), and (2) there is no
   ROA "matching" the attacker's announcement (there is no ROA for AS
   64511 and IP prefix 168.122.0.0/24) [RFC6811].  If routers ignore
   invalid BGP announcements, the minimal ROA above ensures that the
   subprefix hijack will fail.



Gilad, et al.           Expires October 26, 2019                [Page 4]


Internet-Draft               RPKI maxLength                   April 2019


   Now suppose that the "minimal ROA" was replaced with a "loose ROA"
   that used maxLength as a shorthand for set of IP prefixes that AS
   64496 is authorized to originate.  The "loose ROA" would be:

      ROA:(168.122.0.0/16-24, AS 64496)

   This "loose ROA" authorizes AS 64496 to originate any subprefix of
   168.122.0.0/16, up to length /24.  That is, AS 64496 could originate
   168.122.225.0/24 as well as all of 168.122.0.0/17, 168.122.128.0/17,
   ..., 168.122.255.0/24 but not 168.122.0.0/25.

   However, AS 64496 only originates two prefixes in BGP: 168.122.0.0/16
   and 168.122.255.0/24.  This means that all other prefixes authorized
   by the "loose ROA" (for instance, 168.122.0.0/24), are vulnerable to
   the following forged-origin subprefix hijack [RFC7115] [GCHSS]:

      The hijacker AS 64511 sends a BGP announcement "168.122.0.0/24: AS
      64511, AS 64496", falsely claiming that AS 64511 is a neighbor of
      AS 64496 and falsely claiming that AS 64496 originates the IP
      prefix 168.122.0.0/24.  In fact, the IP prefix 168.122.0.0/24 is
      not originated by AS 64496.

   The hijacker's BGP announcement is valid according to the RPKI, since
   the ROA (168.122.0.0/16-24, AS 64496) authorizes AS 64496 to
   originate BGP routes for 168.122.0.0/24.  Because AS 64496 does not
   actually originate a route for 168.122.0.0/24, the hijacker's route
   is the *only* route to the 168.122.0.0/24.  Longest-prefix-match
   routing ensures that the hijacker's route to the subprefix
   168.122.0.0/24 is always preferred over the legitimate route to
   168.122.0.0/16 originated by AS 64496.  Thus, the hijacker's route
   propagates through the Internet, the traffic destined for IP
   addresses in 168.122.0.0/24 will be delivered to the hijacker.

   The forged-origin *subprefix* hijack would have failed if the
   "minimal ROA" described above was used instead of the "loose ROA".
   If the "minimal ROA" had been used instead, the attacker would be
   forced to launch a forged-origin *prefix* hijack in order to attract
   traffic, as follows:

      The hijacker AS 64511 sends a BGP announcement "168.122.0.0/16: AS
      64511, AS 64496", falsely claiming that AS 64511 is a neighbor of
      AS 64496.

   This forged-origin *prefix* hijack is significantly less damaging
   than the forged-origin *subprefix* hijack.  AS 64496 legitimately
   originates 168.122.0.0/16 in BGP, so the hijacker AS 64511 is not
   presenting the *only* route to 168.122.0.0/16.  Moreover, the path
   originated by AS 64511 is one hop longer than the path originated by



Gilad, et al.           Expires October 26, 2019                [Page 5]


Internet-Draft               RPKI maxLength                   April 2019


   the legitimate origin AS 64496.  As discussed in [LSG16], this means
   that the hijacker will attract less traffic than he would have in the
   forged-origin *subprefix* hijack, where the hijacker presents the
   *only* route to the hijacked subprefix.

   In summary, a forged-origin subprefix hijack has the same impact as a
   regular subprefix hijack.  A forged-origin *subprefix* hijack is also
   more damaging than forged-origin *prefix* hijack.

4.  Measurements of Today's RPKI

   Network measurements from June 1, 2017 show that 12% of the IP
   prefixes authorized in ROAs have a maxLength longer than their prefix
   length.  The vast majority of these (84%) are vulnerable to forged-
   origin subprefix hijacks.  These subprefixes are not announced in BGP
   by the legitimate AS.  Even large providers are vulnerable to these
   attacks.  See [GSG17] for details.

   These measurements suggest that operators commonly misconfigure the
   maxLength attribute, and unwittingly open themselves up to forged-
   origin subprefix hijacks.  That is, they are exposing a much larger
   attack surface for forged-origin hijacks than necessary.

5.  Recommendations about Minimal ROAs and Maxlength

   Operators SHOULD avoid using the maxLength attribute in their ROAs
   except in some special cases.  One such exception may be when all
   more specific prefixes permitted by the maxLength are actually
   announced by the AS in the ROA.  Another exception for use of
   maxLength is when (a) the maxLength is substantially larger compared
   to the specified prefix length in the ROA, and (b) a large number of
   more specific prefixes in that range is announced by the AS in the
   ROA.  This case should occur rarely in practice (if at all).
   Operator discretion is necessary in this case.

   Operators SHOULD use "minimal ROAs" whenever possible.  A minimal ROA
   contains only those IP prefixes that are actually originated by an AS
   in BGP, and no other IP prefixes.  (See Section 3 for an example.)

   This practice requires no changes to the RPKI specification and will
   not increase the number of signed ROAs in the RPKI, because ROAs
   already support lists of IP prefixes [RFC6482].  See also [GSG17] for
   further discussion of why this practice will have minimal impact on
   the performance of the RPKI ecosystem.







Gilad, et al.           Expires October 26, 2019                [Page 6]


Internet-Draft               RPKI maxLength                   April 2019


5.1.  Creation of ROAs Facilitating DDoS Mitigation Service

   Sometimes, it is not possible to use a "minimal ROA", because an
   operator wants to issue a ROA that includes an IP prefix that is
   sometimes (but not always) originated in BGP.

   In this case, the ROA SHOULD include (1) the set of IP prefixes that
   are always originated in BGP, and (2) the set IP prefixes that are
   sometimes, but not always, originated in BGP.  The ROA SHOULD NOT
   include any IP prefixes that the operator knows will not be
   originated in BGP.  Whenever possible, the ROA SHOULD also avoid the
   use of the maxLength attribute.

   We now extend our running example to illustrate one situation where
   where it is not possible to issue a minimal ROA.

   Consider the following scenario prior to deployment of RPKI.  Suppose
   AS 64496 announced 168.122.0.0/16 and has a contract with a
   Distributed Denial of Service (DDoS) mitigation service provider that
   holds AS 64500.  Further, assume that the DDoS mitigation service
   contract applies to all IP addresses covered by 168.122.0.0/22.  When
   a DDoS attack is detected and reported by AS 64496, AS 64500
   immediately originates 168.122.0.0/22, thus attracting all the DDoS
   traffic to itself.  The traffic is scrubbed at AS 64500 and then sent
   back to AS 64496 over a backhaul data link.  Notice that, during a
   DDoS attack, the DDoS mitigation service provider AS 64500 originates
   a /22 prefix that is longer than AS 64496's /16 prefix, and so all
   the traffic (destined to addresses in 168.122.0.0/22) that normally
   goes to AS 64496 goes to AS 64500 instead.

   First, suppose the RPKI only had the minimal ROA for AS 64496, as
   described in Section 3.  But, if there is no ROA authorizing AS 64500
   to announce the /22 prefix, then the DDoS mitigation (and traffic
   scrubbing) scheme would not work.  That is, if AS 64500 originates
   the /22 prefix in BGP during DDoS attacks, the announcement would be
   invalid [RFC6811].

   Therefore, the RPKI should have two ROAs: one for AS 64496 and one
   for AS 64500.

      ROA:(168.122.0.0/16,168.122.225.0/24, AS 64496)

      ROA:(168.122.0.0/22, AS 64500)

   Neither ROA uses the maxLength attribute.  But, the second ROA is not
   "minimal" because it contains a /22 prefix that is not originated by
   anyone in BGP during normal operations.  The /22 prefix is only




Gilad, et al.           Expires October 26, 2019                [Page 7]


Internet-Draft               RPKI maxLength                   April 2019


   originated by AS 64500 as part of its DDoS mitigation service during
   a DDoS attack.

   Notice, however, that this scheme does not come without risks.
   Namely, all IP addresses in 168.122.0.0/22 are vulnerable to a
   forged-origin subprefix hijack during normal operations, when the /22
   prefix is not originated.  (The hijacker AS 64511 would send the BGP
   announcement "168.122.0.0/22: AS 64511, AS 64500", falsely claiming
   that AS 64511 is a neighbor of AS 64500 and falsely claiming that AS
   64500 originates 168.122.0.0/22.)

   In some situations, the DDoS mitigation service at AS 64500 might
   want to limit the amount of DDoS traffic that it attracts and scrubs.
   Suppose that a DDoS attack only targets IP addresses in
   168.122.0.0/24.  Then, the DDoS mitigation service at AS 64500 only
   wants to attract the traffic designated for the /24 prefix that is
   under attack, but not the entire /22 prefix.  To allow for this, the
   RPKI should have two ROAs: one for AS 64496 and one for AS 64500.

      ROA:(168.122.0.0/16,168.122.225.0/24, AS 64496)

      ROA:(168.122.0.0/22-24, AS 64500)

   The second ROA uses the maxLength attribute because it is designed to
   explicitly enable AS 64500 to originate *any* /24 subprefix of
   168.122.0.0/22.

   As before, the second ROA is not "minimal" because it contains
   prefixes that are not originated by anyone in BGP during normal
   operations.  As before, all IP addresses in 168.122.0.0/22 are
   vulnerable to a forged-origin subprefix hijack during normal
   operations, when the /22 prefix is not originated.

   The use of maxLength in this second ROA also comes with an additional
   risk.  While it permits the DDoS mitigation service at AS 64500 to
   originate prefix 168.122.0.0/24 during a DDoS attack in that space,
   it also makes the *other* /24 prefixes covered by the /22 prefix
   (i.e., 168.122.1.0/24, 168.122.2.0/24, 168.122.3.0/24) vulnerable to
   a forged-origin subprefix attacks.

   There is another entirely different way of managing ROAs for DDoS
   mitigation service.  In this scheme, ROAs are not pre-created for the
   DDoS mitigation service but are created on the fly when the DDoS
   mitigation service request is made.  Further, the BGP announcements
   for actuating the DDoS mitigation service will not be made until the
   ROAs propagate fully through the RPKI system.  Hence, there would be
   a latency involved in DDoS mitigation service going into effect.
   This method would be effective only if the latency is guaranteed to



Gilad, et al.           Expires October 26, 2019                [Page 8]


Internet-Draft               RPKI maxLength                   April 2019


   be within some acceptable limit.  This calls for mechanisms to be in
   place for RPKI data propagation to occur very fast.  Thus, this
   scheme of managing ROAs for DDoS mitigation service helps with
   eliminating the attack surface for prefixes requiring this service.
   However, the viability of this scheme depends on future work related
   to achieving fast ROA propagation in the global RPKI system.

6.  ROAs and Origin Validation for RTBH Filtering Scenario

   Considerations related to ROAs and origin validation [RFC6811] for
   the case of destination-based Remote Triggered Black Hole (RTBH)
   filtering are addressed here.  In RTBH, highly specific prefixes
   (greater than /24 in IPv4 and greater than /48 in IPv6; possibly even
   /32 (IPv4) and /128 (IPv6)) are announced in BGP.  These
   announcements are tagged with a BLACKHOLE Community [RFC7999].  It is
   obviously not desirable to use large maxlength or include any such
   highly specific prefixes in the ROAs to accommodate destination-based
   RTBH filtering.  Therefore, operators SHOULD accommodate this
   scenario by accepting BGP announcements tagged with BLACKHOLE
   Community only if the following conditions are met: (1) the
   announcement is received on a BGP session on which there is agreement
   to honor BLACKHOLE Community, and (2) the prefix in the announcement
   is covered by a ROA that has an AS number matching with the AS number
   of the peer on that BGP session.

7.  Acknowledgments

   The authors would like to thank the following people for their review
   and contributions to this document: Omar Sagga (Boston University)
   and Aris Lambrianidis (AMS-IX).

8.  References

8.1.  Normative References

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119,
              DOI 10.17487/RFC2119, March 1997,
              <https://www.rfc-editor.org/info/rfc2119>.

   [RFC4271]  Rekhter, Y., Ed., Li, T., Ed., and S. Hares, Ed., "A
              Border Gateway Protocol 4 (BGP-4)", RFC 4271,
              DOI 10.17487/RFC4271, January 2006,
              <https://www.rfc-editor.org/info/rfc4271>.

   [RFC6480]  Lepinski, M. and S. Kent, "An Infrastructure to Support
              Secure Internet Routing", RFC 6480, DOI 10.17487/RFC6480,
              February 2012, <https://www.rfc-editor.org/info/rfc6480>.



Gilad, et al.           Expires October 26, 2019                [Page 9]


Internet-Draft               RPKI maxLength                   April 2019


   [RFC6482]  Lepinski, M., Kent, S., and D. Kong, "A Profile for Route
              Origin Authorizations (ROAs)", RFC 6482,
              DOI 10.17487/RFC6482, February 2012,
              <https://www.rfc-editor.org/info/rfc6482>.

   [RFC6811]  Mohapatra, P., Scudder, J., Ward, D., Bush, R., and R.
              Austein, "BGP Prefix Origin Validation", RFC 6811,
              DOI 10.17487/RFC6811, January 2013,
              <https://www.rfc-editor.org/info/rfc6811>.

8.2.  Informative References

   [GCHSS]    Gilad, Y., Cohen, A., Herzberg, A., Schapira, M., and H.
              Shulman, "Are We There Yet? On RPKI's Deployment and
              Security", in NDSS 2017, February 2017,
              <https://eprint.iacr.org/2016/1010.pdf>.

   [GSG17]    Gilad, Y., Sagga, O., and S. Goldberg, "Maxlength
              Considered Harmful to the RPKI", in ACM CoNEXT 2017,
              December 2017, <https://eprint.iacr.org/2016/1015.pdf>.

   [HARMFUL]  Gilad, Y., Sagga, O., and S. Goldberg, "MaxLength
              Considered Harmful to the RPKI", 2017,
              <https://eprint.iacr.org/2016/1015.pdf>.

   [LSG16]    Lychev, R., Shapira, M., and S. Goldberg, "Rethinking
              Security for Internet Routing", in Communications of the
              ACM, October 2016, <http://cacm.acm.org/
              magazines/2016/10/207763-rethinking-security-for-internet-
              routing/>.

   [RFC6907]  Manderson, T., Sriram, K., and R. White, "Use Cases and
              Interpretations of Resource Public Key Infrastructure
              (RPKI) Objects for Issuers and Relying Parties", RFC 6907,
              DOI 10.17487/RFC6907, March 2013,
              <https://www.rfc-editor.org/info/rfc6907>.

   [RFC7115]  Bush, R., "Origin Validation Operation Based on the
              Resource Public Key Infrastructure (RPKI)", BCP 185,
              RFC 7115, DOI 10.17487/RFC7115, January 2014,
              <https://www.rfc-editor.org/info/rfc7115>.

   [RFC7999]  King, T., Dietzel, C., Snijders, J., Doering, G., and G.
              Hankins, "BLACKHOLE Community", RFC 7999,
              DOI 10.17487/RFC7999, October 2016,
              <https://www.rfc-editor.org/info/rfc7999>.





Gilad, et al.           Expires October 26, 2019               [Page 10]


Internet-Draft               RPKI maxLength                   April 2019


   [RFC8205]  Lepinski, M., Ed. and K. Sriram, Ed., "BGPsec Protocol
              Specification", RFC 8205, DOI 10.17487/RFC8205, September
              2017, <https://www.rfc-editor.org/info/rfc8205>.

Authors' Addresses

   Yossi Gilad
   Boston University
   111 Cummington St, MCS135
   Boston, MA  02215
   USA

   EMail: yossigi@bu.edu


   Sharon Goldberg
   Boston University
   111 Cummington St, MCS135
   Boston, MA  02215
   USA

   EMail: goldbe@cs.bu.edu


   Kotikalapudi Sriram
   USA National Institute of Standards and Technology
   100 Bureau Drive
   Gaithersburg, MD  20899
   USA

   EMail: kotikalapudi.sriram@nist.gov


   Job Snijders
   NTT Communications
   Theodorus Majofskistraat 100
   Amsterdam  1065 SZ
   The Netherlands

   EMail: job@ntt.net











Gilad, et al.           Expires October 26, 2019               [Page 11]


Internet-Draft               RPKI maxLength                   April 2019


   Ben Maddison
   Workonline Communications
   30 Waterkant St
   Cape Town  8001
   South Africa

   EMail: benm@workonline.co.za












































Gilad, et al.           Expires October 26, 2019               [Page 12]


Html markup produced by rfcmarkup 1.129c, available from https://tools.ietf.org/tools/rfcmarkup/