Publishing End-Site Prefix Lengths

Publishing End-Site Prefix Lengths IPinfo

oliver@ipinfo.io

IIJ Research & Arrcus

5147 Crystal Springs Bainbridge Island Washington 98110 United States of America randy@psg.com

NTT

Siriusdreef 70-72 Hoofddorp 2132 WT Netherlands massimo@ntt.net

Vigil Security, LLC

516 Dranesville Road Herndon VA 20170 United States of America housley@vigilsec.com

prefix allocation RPSL inetnum This document specifies how to augment the Routing Policy Specification Language (RPSL) inetnum: class to refer specifically to prefixlen files, which are Comma-Separated Values (CSV) files used to specify end-site prefix lengths. This document also describes an optional mechanism that uses the Resource Public Key Infrastructure (RPKI) to authenticate the prefixlen files.

Status of This Memo This is an Internet Standards Track document. This document is a product of the Internet Engineering Task Force (IETF). It represents the consensus of the IETF community. It has received public review and has been approved for publication by the Internet Engineering Steering Group (IESG). Further information on Internet Standards is available in Section 2 of RFC 7841. Information about the current status of this document, any errata, and how to provide feedback on it may be obtained at .

Copyright Notice Copyright (c) 2026 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 () 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 Revised BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Revised BSD License.

Table of Contents

. Introduction
. Requirements Language
. prefixlen Files
- . End-Site Prefix Length Without CGN or Proxies
- . End-Site Prefix Length with CGN or Proxies
- . Longest Prefix Matching
- . Not Specifying Any End-Site Prefix Length
- . Processing prefixlen Files
. inetnum: Class
. Fetching prefixlen Data
. Authenticating prefixlen Data (Optional)
. Operational Considerations
. Implementation Status
. Security Considerations
. IANA Considerations
. References
- . Normative References
- . Informative References
. ASN.1 Module
. Example
Acknowledgments
Authors' Addresses

Introduction Internet Service Providers (ISPs) delegate IP addresses or entire IP prefixes to their users. Similarly, cloud providers assign customers who use their services, such as virtual machines (VMs), a prefix of a specific size. Therefore, there are many variations of end-site prefix lengths present in the Internet. Currently, there is no easy way for content providers to know the end-site prefix size of someone accessing their service. Knowing the correct end-site's prefix size has multiple implications such as:

Blocklisting/throttling:: In IPv4, IP addresses can be blocked using variable prefix lengths for different prefixes, such as /22 for prefix A, /27 for prefix B, or /32 to block a single IPv4 address. Due to the large address space in IPv6, blocking at, e.g., the /48 or /56 level could lead to overblocking (throwing multiple VMs from different users into the same bucket), while blocking at more fine-granular levels, e.g., /64, /96, or even /128, to block a single IPv6 address would lead to filling up space in the blocklist pretty quickly. The use of temporary addresses in IPv6 might lead to unwanted unblocking when addresses are blocked at a too-fine-granular level (e.g., /128). All these issues apply to throttling as well.
Rate limiting/CAPTCHAs:: A similar issue arises on the Web, where neighboring prefixes might be thrown together (e.g., in the same /48 or /56 even though the ISP hands out /64s), which leads to people "jointly" running into rate limits and then either being blocked from a service or having to solve annoying CAPTCHAs.
Geolocation:: Getting the right prefix size for geolocation is similarly difficult, especially for IPv6. If you aggregate too much, you throw together different clients in different locations; if you aggregate too little, you fill up the geolocation database with unnecessary entries.

This document specifies how to augment the Routing Policy Specification Language (RPSL) inetnum: class to refer specifically to prefixlen files and how to use the files. In all places where inetnum: is used, inet6num: must also be assumed . The reader may find informative, with certainly more verbose descriptions, on the inetnum: and inet6num database classes. An optional means for authenticating prefixlen data is also defined in .

Requirements Language The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in BCP 14 when, and only when, they appear in all capitals, as shown here.

prefixlen Files prefixlen files are CSV files in text format with UTF-8 encoding , excluding problematic code points as described in . Lines MUST be delimited by a line break (CRLF), and blank lines MUST be ignored. Text from a '#' character to the end of the current line MUST be treated as a comment only and is similarly ignored. The first field of each line that is not ignored specifies the prefix in question, the second the end-site prefix length within that prefix as an integer, and the third the number of end-sites within an end-site prefix length for networks using Carrier-Grade NAT (CGN) or proxies. In all places Carrier-Grade NAT or CGN is used in this document, the specifications apply to proxies as well. Note that all three fields MUST be present. This means there MUST be exactly two commas in each non-commented line delimiting the three fields. The first field MUST NOT be empty on lines that are not comments, while the second and third field can be empty in certain scenarios. If both the second and third fields are empty, the publisher does not want to disclose any prefix length information.

End-Site Prefix Length Without CGN or Proxies If an ISP delegates /56 IPv6 prefixes of the 2001:db8::/32 range and /32 IPv4 prefixes (i.e., a single IPv4 address) of the 192.0.2.0/24 range to its customers without the use of CGN or proxy techniques, it would create a prefix length file containing the following example entries: 2001:db8::/32,56,1 192.0.2.0/24,32,1 Note the third field being set to '1', which signals the absence of CGN or proxies. This has the same meaning as the third field being left empty in this scenario.

End-Site Prefix Length with CGN or Proxies prefixlen files can also be used to signal the presence of CGN or proxies in networks. This is especially useful for cases where multiple end-sites behind a CGN or proxy service accessing a service at the same time might run into rate-limiting issues by service providers. If a prefixlen file signals the presence of a CGN, service providers can treat these prefixes in a way that rate limits are adjusted. To signal the presence of a CGN, the number of CGN end-sites is specified in the third field. For example, a CGN prefix 192.0.2.0/24 containing 4000 CGN end-sites would be specified as follows: 192.0.2.0/24,24,4000 Note the second field in the above example is set to '24', signaling that the 4000 CGN end-sites are present in the complete 192.0.2.0/24 prefix. On the other hand, if these 4000 CGN end-sites are distributed 1000 each in the four /26 sub-prefixes within 192.0.2.0/24, this is specified as follows: 192.0.2.0/24,26,1000 It is important to note that the third field denoting the number of CGN end-sites is referring to the prefix length specified in the second field. Note that this specification can be applied to IPv6 networks as well.

Longest Prefix Matching Prefix length files can contain sub-prefix entries of a parent prefix; this needs to be taken into account when processing these files. For example, if a cloud provider assigns /120 IPv6 prefixes to each customer VM and a /64 prefix to premium customers, it would create a prefix length file containing the following example entries: 2001:db8::/32,120, 2001:db8:abcd::/48,64, Note that the second entry in the above example is a subprefix of the first entry. Therefore, longest prefix matching has to be performed when parsing prefixlen files.

Not Specifying Any End-Site Prefix Length If an ISP delegates /32 IPv4 prefixes (i.e., a single IPv4 address) of the 192.0.2.0/24 range to its customers without the use of CGN, and it has a special sub-prefix 192.0.2.0/28 where this policy does not apply, it can signal so with the following prefix length file: 192.0.2.0/24,32, 192.0.2.0/28,, If both the second and third fields are empty, the publisher does not want to disclose any prefix length information. Any prefix length information from covering prefixes (192.0.2.0/24 in our example) MUST be discarded for sub-prefixes specified in prefixlen files (192.0.2.0/28 in our example).

Processing prefixlen Files Multiple entries with exactly the same prefix MUST be considered an error, and consumer implementations SHOULD log the repeated entries for further administrative review. Publishers MUST take measures to ensure there is one and only one entry per prefix. Upon encountering an erroneous entry in a prefixlen file, consumer implementations MUST skip that entry, log the error, and continue processing the remaining entries. Content providers and other parties who wish to differentiate services based on end-site prefixes need to find the relevant prefixlen data. specifies how to find the relevant prefixlen file given an IP address. prefixlen data for large providers administrating a large number of networks and end-sites can contain millions of entries. The size of a file can be even larger if an unsigned prefixlen file combines data for many prefixes, if dual IPv4/IPv6 spaces are represented, etc. This document also suggests an optional signature to strongly authenticate the data in the prefixlen files. The same approach to signatures is used in this document that was used in .

inetnum: Class The original RPSL specifications (, , and a trail of subsequent documents) were written by the RIPE community. The IETF standardized RPSL in and . Since then, it has been modified and extensively enhanced in the Regional Internet Registry (RIR) community, mostly by RIPE . At the time of publication, change control of RPSL effectively lies in the operator community. The RPSL, and and used by the RIRs, specify the inetnum: database class. Each of these objects describes an IP address range and its attributes. The inetnum: objects form a hierarchy ordered on the address space. Ideally, RPSL would be augmented to define a new RPSL prefixlen: attribute in the inetnum: class. Absent implementation of the prefixlen: attribute in a particular RIR database, this document defines the syntax of a prefixlen remarks: attribute, which contains an HTTPS URL of a prefixlen file. The format of the inetnum: prefixlen remarks: attribute MUST be as in this example, "remarks: Prefixlen ", where the token "Prefixlen" MUST be case-sensitive, followed by a URL that will vary but that MUST refer only to a single prefixlen file. inetnum: 192.0.2.0/24 # example remarks: Prefixlen https://example.com/prefixlen While we leave global agreement of RPSL modification to the relevant parties, we specify that a proper prefixlen: attribute in the inetnum: class MUST be "prefixlen:" and MUST be followed by a single URL that will vary, but it MUST refer only to a single prefixlen file. inetnum: 192.0.2.0/24 # example prefixlen: https://example.com/prefixlen The URL uses HTTPS, so the Web Public Key Infrastructure (WebPKI) provides authentication, integrity, and confidentiality for the fetched prefixlen file. However, the WebPKI cannot provide authentication of IP address space assignment. In contrast, the RPKI (see ) can be used to authenticate IP space assignment; see optional authentication in . Until all producers of inetnum: objects, i.e., the RIRs, state that they have migrated to supporting the prefixlen: attribute, consumers looking at inetnum: objects to find prefixlen URLs MUST be able to consume the remarks: and prefixlen: forms. The migration not only implies that the RIRs support the prefixlen: attribute, but that all registrants have migrated any inetnum: objects from remarks: to prefixlen:. Any particular inetnum: object SHOULD have, at most, one prefixlen reference, whether a remarks: or prefixlen: attribute when it is implemented. As the remarks: form cannot be formally checked by the RIR, this cannot be formally enforced. A prefixlen: attribute is preferred, of course, if the RIR supports it. If there is more than one type of attribute in the inetnum: object, the prefixlen: attribute MUST be prioritized over the remarks: attribute. For inetnum: instances covering the same address range, a signed prefixlen file MUST be preferred over an unsigned file. If none are signed, or more than one is signed, the (signed) inetnum: with the most recent last-modified: attribute MUST be preferred. If a prefixlen file describes multiple disjoint ranges of IP address space, there are likely to be prefixlen references from multiple inetnum: objects. Files with prefixlen references from multiple inetnum: objects are not compatible with the signing procedure in . An unsigned, and only an unsigned, prefixlen file MAY be referenced by multiple inetnum: instances and MAY contain prefixes from more than one registry. When fetching, the most specific inetnum: object with a prefixlen reference MUST be used. It is significant that prefixlen data may have finer granularity than the inetnum: that refers to them. For example, an inetnum: object for an address range P could refer to a prefixlen file in which P has been subdivided into one or more longer prefixes. Backward-compatibility issues regarding the implementation of new RPSL attributes are covered by .

Fetching prefixlen Data This document provides a guideline for how interested parties should fetch and read prefixlen files. To minimize the load on RIRs' WHOIS services, the RIR's bulk-download services SHOULD be used for large-scale access to gather inetnum: instances with prefixlen references. This uses efficient bulk access instead of fetching via brute-force search through the IP space. When using bulk-download services, they MUST be accessed using HTTPS ; FTP MUST NOT be used. On the other hand, RIRs are converging on RDAP support, which includes geofeed data; see . It is hoped that this will be extended, or generalized, to support prefixlen data. When reading data from a prefixlen file, one MUST ignore data outside the referring inetnum: object's address range. This is to avoid importing data about ranges not under the control of the operator. Note that signed files MUST only contain prefixes within the referring inetnum:'s range as mandated in . If prefixlen files are fetched, other prefix length information from the inetnum: MUST be ignored. Given an address range of interest, the most specific inetnum: object with a prefixlen reference MUST be used to fetch the prefixlen file. For example, if the fetching party finds the following inetnum: objects: inetnum: 192.0.2.0/24 # example remarks: Prefixlen https://example.com/prefixlen_1 inetnum: 192.0.2.0/26 # example remarks: Prefixlen https://example.com/prefixlen_2 An application looking for prefixlen data for 192.0.2.0/29 MUST ignore data in prefixlen_1 because 192.0.2.0/29 is within the more specific 192.0.2.0/26 inetnum: covering that address range and that inetnum: does have a prefixlen reference.

Authenticating prefixlen Data (Optional) The question arises whether a particular prefixlen data set is valid, i.e., is authorized by the "owner" of the IP address space and is authoritative in some sense. The inetnum: that points to the prefixlen file provides some assurance. Unfortunately, the RPSL in some repositories is weakly authenticated at best. An approach where RPSL was signed per the guidance in would be good, except it would have to be deployed by all RPSL registries, and there is a fair number of them. The remainder of this section specifies an optional authenticator for the prefixlen data set that follows the Signed Object Template for the Resource Public Key Infrastructure (RPKI) . A single optional authenticator MAY be appended to a prefixlen file. It is a digest of the main body of the file signed by the private key of the relevant RPKI certificate for a covering address range. The following format bundles the relevant RPKI certificate with a signature over the prefixlen text. The canonicalization procedure converts the data from their internal character representation to the UTF-8 character encoding (see ), and the <CRLF> sequence MUST be used to denote the end of each line of text. A blank line is represented solely by the <CRLF> sequence. For robustness, any non-printable characters MUST NOT be changed by canonicalization. Trailing blank lines MUST NOT appear at the end of the file. That is, the file must not end with multiple consecutive <CRLF> sequences. Any end-of-file marker used by an operating system is not considered to be part of the file content. When present, such end-of-file markers MUST NOT be covered by the digital signature. If the authenticator is not in the canonical form described above, then the authenticator is invalid, which means that it is treated in the same manner as an unauthenticated prefixlen data. Borrowing detached signatures from , after file canonicalization, the CMS (see ) is used to create a detached DER-encoded signature that is then Base64-encoded with padding (as defined in ) and line wrapped to 72 or fewer characters. The same digest algorithm MUST be used for calculating the message digest of the content being signed, which is the prefixlen file, and for calculating the message digest on the SignerInfo SignedAttributes (see ). The message digest algorithm identifier MUST appear in both the CMS SignedData DigestAlgorithmIdentifiers and the SignerInfo DigestAlgorithmIdentifier . The RPKI certificate covering the prefixlen inetnum: object's address range is included in the CMS SignedData certificates field . The address range of the signing certificate MUST cover all prefixes in the signed prefixlen file. If not, the authenticator is invalid. The signing certificate MUST NOT include the Autonomous System Identifier Delegation certificate extension . If it is present, the authenticator is invalid. As with many other RPKI signed objects, the IP Address Delegation certificate extension MUST NOT use the "inherit" capability defined in . If "inherit" is used, the authenticator is invalid. An IP Address Delegation certificate extension using "inherit" would complicate processing. The implementation would have to build the certification path from the end-entity to the trust anchor and then validate the path from the trust anchor to the end-entity. Then, the parameter would have to be remembered when the validated public key was used to validate a signature on a CMS object. Having to remember things from certification-path validation for use with CMS object processing would be quite complex and error-prone. And, the certificates do not get that much bigger by repeating the information. An address range A "covers" address range B if the range of B is identical to or a subset of A. "Address range" is used here because inetnum: objects and RPKI certificates need not align on Classless Inter-Domain Routing (CIDR) prefix boundaries, while those of the lines in a prefixlen file do align. The Certification Authority (CA) MUST generate a new End Entity (EE) certificate for each signing of a particular prefixlen file. The private key associated with the EE certificate SHOULD sign only one prefixlen file. That is, a new key pair SHOULD be generated for each new version of a particular prefixlen file. When the EE certificate is used in this fashion, it is termed a "one-time-use" EE certificate (see ). On the other hand, verifying the signature has no similar complexity; the certificate, which is validated in the RPKI, contains the needed public key. The RPKI trust anchors for the RIRs are available to the party performing signature validation. Validation of the CMS signature over the prefixlen file involves:

Obtaining the signer's certificate from the CMS SignedData CertificateSet . The certificate SubjectKeyIdentifier extension MUST match the SubjectKeyIdentifier in the CMS SignerInfo SignerIdentifier . If the key identifiers do not match, then validation MUST fail.
Validating the signer's certificate MUST ensure that it is part of the current manifest per and that all resources are covered by the RPKI certificate.
Constructing and validating the certification path for the signer's certificate. All of the needed certificates are expected to be readily available in the RPKI repository. The certification path MUST be valid according to the validation algorithm in and the additional checks specified in associated with the IP Address Delegation certificate extension. If certification path validation is unsuccessful, then validation MUST fail.
Validating the CMS SignedData as specified in using the public key from the validated signer's certificate. If the signature validation is unsuccessful, then validation MUST fail.
Confirming that the eContentType Object IDentifier (OID) is id-ct-prefixlenCSVwithCRLF (1.2.840.113549.1.9.16.1.57). This OID MUST appear within both the eContentType in the encapContentInfo object and the ContentType signed attribute in the signerInfo object (see ).
Verifying that the IP Address Delegation certificate extension covers all of the address ranges of the prefixlen file. If all of the address ranges are not covered, then validation MUST fail.

All of the above steps MUST be successful to consider the prefixlen file signature to be valid. The authenticator MUST be hidden as a series of "#" comments at the end of the prefixlen file. The following simple example is cryptographically incorrect: # RPKI Signature: 192.0.2.0 - 192.0.2.255 # MIIGlwYJKoZIhvcNAQcCoIIGiDCCBoQCAQMxDTALBglghkgBZQMEAgEwDQYLKoZ # IhvcNAQkQAS+gggSxMIIErTCCA5WgAwIBAgIUJ605QIPX8rW5m4Zwx3WyuW7hZu ... # imwYkXpiMxw44EZqDjl36MiWsRDLdgoijBBcGbibwyAfGeR46k5raZCGvxG+4xa # O8PDTxTfIYwAnBjRBKAqAZ7yX5xHfm58jUXsZJ7Ileq1S7G6Kk= # End Signature: 192.0.2.0 - 192.0.2.255 A correct and full example is in . The CMS signature does not cover the signature lines. The bracketing "# RPKI Signature:" and "# End Signature:" MUST be present as shown in the example. The RPKI Signature's IP address range MUST match that of the prefixlen URL in the inetnum: that points to the prefixlen file.

Operational Considerations To create the needed inetnum: objects, an operator wishing to register the location of their prefixlen file needs to coordinate with their Regional Internet Registry (RIR) or National Internet Registry (NIR) and/or any provider Local Internet Registry (LIR) that has assigned address ranges to them. RIRs/NIRs provide means for assignees to create and maintain inetnum: objects. They also provide means of assigning or sub-assigning IP address resources and allowing the assignee to create WHOIS data, including inetnum: objects, thereby referring to prefixlen files. The prefixlen files MUST be published via and fetched using HTTPS . When using data from a prefixlen file, one MUST ignore data outside the referring inetnum: object's inetnum: attribute address range. If and only if the prefixlen file is not signed per , then multiple inetnum: objects MAY refer to the same prefixlen file, and the consumer MUST use only lines in the prefixlen file where the prefix is covered by the address range of the inetnum: object's URL it has followed. If the prefixlen file is signed, and the signer's certificate is replaced with another certificate, then the signature in the prefixlen file MUST be updated so that it can be properly validated with the new certificate. It is good key hygiene to use a given key for only one purpose. To dedicate a signing private key for signing a prefixlen file, an RPKI Certification Authority (CA) may issue a subordinate certificate exclusively for the purpose shown in . Harvesting and publishing aggregated prefixlen data outside of the RPSL model SHOULD be avoided: it can have the effect that more specifics from one aggregatee could undesirably affect the less specifics of a different aggregatee. Moreover, publishing aggregated prefixlen data prevents the reader of the data to perform the checks described in Sections and . An anonymized version of bulk WHOIS data is openly available for all RIRs except ARIN, which requires an authorization. However, for users without such authorization, the same result can be achieved with extra RDAP effort. There is open-source code to pass over such data across all RIRs, collect all prefixlen references, and process them . To prevent undue load on RPSL and prefixlen servers, entity-fetching prefixlen data using these mechanisms MUST NOT do frequent real-time lookups. prefixlen servers SHOULD send an HTTP Expires header to signal when prefixlen data should be refetched. If an HTTP Expires or Cache-Control header is present, it MUST be honored by clients. As the data change very infrequently, in the absence of such an HTTP header signal, collectors SHOULD NOT fetch more frequently than weekly. It would be polite not to fetch at magic times such as midnight UTC, the first of the month, etc., because too many others are likely to do the same.

Implementation Status As of November 2025, the prefixlen: attribute in inetnum objects has been implemented by the RIPE NCC database. Registrants in databases that do not yet support the prefixlen: attribute are using the remarks:, or equivalent, attribute. At the time of publication, the registry data published by ARIN are not the same RPSL as that of the other registries (see for a survey of the WHOIS Tower of Babel); therefore, when fetching via bulk WHOIS over HTTPS , WHOIS , the Registration Data Access Protocol (RDAP) , etc., the "NetRange" or "ip network" attribute/key must be treated as "inetnum" and the "Comment" attribute must be treated as "remarks".

Security Considerations The consumer of prefixlen data SHOULD fetch and process the data themselves. Importing datasets produced and/or processed by a third party places significant trust in the third party. As mentioned in , some RPSL repositories have weak, if any, authentication. This allows spoofing of inetnum: objects pointing to malicious prefixlen files. suggests an unfortunately complex method for stronger authentication based on the RPKI. For example, if an inetnum: for a wide address range (e.g., a /16) points to an RPKI-signed prefixlen file, a customer or attacker could publish an unsigned equal or narrower (e.g., a /24) inetnum: in a WHOIS registry that has weak authorization, abusing the rule that the most-specific inetnum: object with a prefixlen reference MUST be used. If signatures were mandatory, the above attack would be stymied, but, of course, that is not happening anytime soon. The RPSL providers have had to throttle fetching from their servers due to too-frequent queries. Usually, they throttle by the querying IP address or block. Similar defenses will likely need to be deployed by prefixlen file servers. As prefixlen files disclose which parts of a prefix belong to an end-site, attackers could better focus DDoS traffic towards a website hosted by a cloud provider by overwhelming only IP addresses from that specific end-site. Furthermore, information collected from prefixlen files could allow for more targeted IPv6 scanning/reconnaissance, where scanners (be it benevolent or malicious ones) can target specific sub-prefixes that they deem more interesting. It is possible for publishers of prefixlen data to specify incorrect prefixlen data about their prefixes. This could be done either by mistake or on purpose. One example could be a malicious network operator trying to overflow the storage of databases that consume prefixlen data by setting a very specific prefix size (e.g., /128 for large blocks of IPv6 address space). In another example, a network operator might annotate their prefixes as using CGN to go around legitimate blocking or throttling. A third example would be a malicious provider publishing fake small allocations, so on receipt of complaints, they could plausibly respond by saying that they stopped the actions of a bad customer and move their malicious activities to a different prefix. As a fourth example, network operators could overwhelm consumers by publishing prefixlen files containing millions or even billions of entries (e.g., enumerating all possible /96 subprefixes of a /32 IPv6 prefix). Therefore, care should be taken when processing prefixlen data, as with any external third-party data.

IANA Considerations IANA has registered an object identifier for one ASN.1 Module in the "SMI Security for S/MIME Module Identifier (1.2.840.113549.1.9.16.0)" registry as follows:

Description	OID	Reference
id-mod-prefixlen-2025	1.2.840.113549.1.9.16.0.87	RFC 9977

IANA has registered an object identifier for one content type in the "SMI Security for S/MIME CMS Content Type (1.2.840.113549.1.9.16.1)" registry as follows:

Description	OID	Reference
id-ct-prefixlenCSVwithCRLF	1.2.840.113549.1.9.16.1.57	RFC 9977

References Normative References Key words for use in RFCs to Indicate Requirement Levels In many standards track documents several words are used to signify the requirements in the specification. These words are often capitalized. This document defines these words as they should be interpreted in IETF documents. This document specifies an Internet Best Current Practices for the Internet Community, and requests discussion and suggestions for improvements. Routing Policy Specification Language (RPSL) RPSL allows a network operator to be able to specify routing policies at various levels in the Internet hierarchy; for example at the Autonomous System (AS) level. At the same time, policies can be specified with sufficient detail in RPSL so that low level router configurations can be generated from them. RPSL is extensible; new routing protocols and new protocol features can be introduced at any time. [STANDARDS-TRACK] Routing Policy System Security The implementation and deployment of a routing policy system must maintain some degree of integrity to be of any operational use. This document addresses the need to assure integrity of the data by providing an authentication and authorization model. [STANDARDS-TRACK] UTF-8, a transformation format of ISO 10646 ISO/IEC 10646-1 defines a large character set called the Universal Character Set (UCS) which encompasses most of the world's writing systems. The originally proposed encodings of the UCS, however, were not compatible with many current applications and protocols, and this has led to the development of UTF-8, the object of this memo. UTF-8 has the characteristic of preserving the full US-ASCII range, providing compatibility with file systems, parsers and other software that rely on US-ASCII values but are transparent to other values. This memo obsoletes and replaces RFC 2279. X.509 Extensions for IP Addresses and AS Identifiers This document defines two X.509 v3 certificate extensions. The first binds a list of IP address blocks, or prefixes, to the subject of a certificate. The second binds a list of autonomous system identifiers to the subject of a certificate. These extensions may be used to convey the authorization of the subject to use the IP addresses and autonomous system identifiers contained in the extensions. [STANDARDS-TRACK] Routing Policy Specification Language next generation (RPSLng) This memo introduces a new set of simple extensions to the Routing Policy Specification Language (RPSL), enabling the language to document routing policies for the IPv6 and multicast address families currently used in the Internet. [STANDARDS-TRACK] Common Format and MIME Type for Comma-Separated Values (CSV) Files This RFC documents the format used for Comma-Separated Values (CSV) files and registers the associated MIME type "text/csv". This memo provides information for the Internet community. The Base16, Base32, and Base64 Data Encodings This document describes the commonly used base 64, base 32, and base 16 encoding schemes. It also discusses the use of line-feeds in encoded data, use of padding in encoded data, use of non-alphabet characters in encoded data, use of different encoding alphabets, and canonical encodings. [STANDARDS-TRACK] Internet X.509 Public Key Infrastructure Certificate and Certificate Revocation List (CRL) Profile This memo profiles the X.509 v3 certificate and X.509 v2 certificate revocation list (CRL) for use in the Internet. An overview of this approach and model is provided as an introduction. The X.509 v3 certificate format is described in detail, with additional information regarding the format and semantics of Internet name forms. Standard certificate extensions are described and two Internet-specific extensions are defined. A set of required certificate extensions is specified. The X.509 v2 CRL format is described in detail along with standard and Internet-specific extensions. An algorithm for X.509 certification path validation is described. An ASN.1 module and examples are provided in the appendices. [STANDARDS-TRACK] Cryptographic Message Syntax (CMS) This document describes the Cryptographic Message Syntax (CMS). This syntax is used to digitally sign, digest, authenticate, or encrypt arbitrary message content. [STANDARDS-TRACK] Additional New ASN.1 Modules for the Cryptographic Message Syntax (CMS) and the Public Key Infrastructure Using X.509 (PKIX) The Cryptographic Message Syntax (CMS) format, and many associated formats, are expressed using ASN.1. The current ASN.1 modules conform to the 1988 version of ASN.1. This document updates some auxiliary ASN.1 modules to conform to the 2008 version of ASN.1; the 1988 ASN.1 modules remain the normative version. There are no bits- on-the-wire changes to any of the formats; this is simply a change to the syntax. This document is not an Internet Standards Track specification; it is published for informational purposes. A Profile for Resource Certificate Repository Structure This document defines a profile for the structure of the Resource Public Key Infrastructure (RPKI) distributed repository. Each individual repository publication point is a directory that contains files that correspond to X.509/PKIX Resource Certificates, Certificate Revocation Lists and signed objects. This profile defines the object (file) naming scheme, the contents of repository publication points (directories), and a suggested internal structure of a local repository cache that is intended to facilitate synchronization across a distributed collection of repository publication points and to facilitate certification path construction. [STANDARDS-TRACK] A Profile for X.509 PKIX Resource Certificates This document defines a standard profile for X.509 certificates for the purpose of supporting validation of assertions of "right-of-use" of Internet Number Resources (INRs). The certificates issued under this profile are used to convey the issuer's authorization of the subject to be regarded as the current holder of a "right-of-use" of the INRs that are described in the certificate. This document contains the normative specification of Certificate and Certificate Revocation List (CRL) syntax in the Resource Public Key Infrastructure (RPKI). This document also specifies profiles for the format of certificate requests and specifies the Relying Party RPKI certificate path validation procedure. [STANDARDS-TRACK] Signed Object Template for the Resource Public Key Infrastructure (RPKI) This document defines a generic profile for signed objects used in the Resource Public Key Infrastructure (RPKI). These RPKI signed objects make use of Cryptographic Message Syntax (CMS) as a standard encapsulation format. [STANDARDS-TRACK] Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words RFC 2119 specifies common key words that may be used in protocol specifications. This document aims to reduce the ambiguity by clarifying that only UPPERCASE usage of the key words have the defined special meanings. Update to the Cryptographic Message Syntax (CMS) for Algorithm Identifier Protection This document updates the Cryptographic Message Syntax (CMS) specified in RFC 5652 to ensure that algorithm identifiers in signed-data and authenticated-data content types are adequately protected. HTTP Semantics The Hypertext Transfer Protocol (HTTP) is a stateless application-level protocol for distributed, collaborative, hypertext information systems. This document describes the overall architecture of HTTP, establishes common terminology, and defines aspects of the protocol that are shared by all versions. In this definition are core protocol elements, extensibility mechanisms, and the "http" and "https" Uniform Resource Identifier (URI) schemes. This document updates RFC 3864 and obsoletes RFCs 2818, 7231, 7232, 7233, 7235, 7538, 7615, 7694, and portions of 7230. Manifests for the Resource Public Key Infrastructure (RPKI) This document defines a "manifest" for use in the Resource Public Key Infrastructure (RPKI). A manifest is a signed object (file) that contains a listing of all the signed objects (files) in the repository publication point (directory) associated with an authority responsible for publishing in the repository. For each certificate, Certificate Revocation List (CRL), or other type of signed objects issued by the authority that are published at this repository publication point, the manifest contains both the name of the file containing the object and a hash of the file content. Manifests are intended to enable a relying party (RP) to detect certain forms of attacks against a repository. Specifically, if an RP checks a manifest's contents against the signed objects retrieved from a repository publication point, then the RP can detect replay attacks, and unauthorized in-flight modification or deletion of signed objects. This document obsoletes RFC 6486. Unicode Character Repertoire Subsets This document discusses subsets of the Unicode character repertoire for use in protocols and data formats and specifies three subsets recommended for use in IETF specifications. Information technology - Abstract Syntax Notation One (ASN.1): Specification of basic notation ITU-T Informative References Descriptions of Primary Objects RIPE NCC prefixlen-finder commit 5f446617796bc17d7e9495513537438ec26ab8e6 File Transfer Protocol This memo is the official specification of the File Transfer Protocol (FTP) for the DARPA Internet community. The primary intent is to clarify and correct the documentation of the FTP specification, not to change the protocol. The following new optional commands are included in this edition of the specification: Change to Parent Directory (CDUP), Structure Mount (SMNT), Store Unique (STOU), Remove Directory (RMD), Make Directory (MKD), Print Directory (PWD), and System (SYST). Note that this specification is compatible with the previous edition. WHOIS Protocol Specification This document updates the specification of the WHOIS protocol, thereby obsoleting RFC 954. The update is intended to remove the material from RFC 954 that does not have to do with the on-the-wire protocol, and is no longer applicable in today's Internet. This document does not attempt to change or update the protocol per se, or document other uses of the protocol that have come into existence since the publication of RFC 954. [STANDARDS-TRACK] Classless Inter-domain Routing (CIDR): The Internet Address Assignment and Aggregation Plan This memo discusses the strategy for address assignment of the existing 32-bit IPv4 address space with a view toward conserving the address space and limiting the growth rate of global routing state. This document obsoletes the original Classless Inter-domain Routing (CIDR) spec in RFC 1519, with changes made both to clarify the concepts it introduced and, after more than twelve years, to update the Internet community on the results of deploying the technology described. This document specifies an Internet Best Current Practices for the Internet Community, and requests discussion and suggestions for improvements. Digital Signatures on Internet-Draft Documents This document specifies the conventions for digital signatures on Internet-Drafts. The Cryptographic Message Syntax (CMS) is used to create a detached signature, which is stored in a separate companion file so that no existing utilities are impacted by the addition of the digital signature. This memo provides information for the Internet community. IANA-Reserved IPv4 Prefix for Shared Address Space This document requests the allocation of an IPv4 /10 address block to be used as Shared Address Space to accommodate the needs of Carrier- Grade NAT (CGN) devices. It is anticipated that Service Providers will use this Shared Address Space to number the interfaces that connect CGN devices to Customer Premises Equipment (CPE). Shared Address Space is distinct from RFC 1918 private address space because it is intended for use on Service Provider networks. However, it may be used in a manner similar to RFC 1918 private address space on routing equipment that is able to do address translation across router interfaces when the addresses are identical on two different interfaces. Details are provided in the text of this document. This document details the allocation of an additional special-use IPv4 address block and updates RFC 5735. This memo documents an Internet Best Current Practice. Inventory and Analysis of WHOIS Registration Objects WHOIS output objects from registries, including both Regional Internet Registries (RIRs) and Domain Name Registries (DNRs), were collected and analyzed. This document describes the process and results of the statistical analysis of existing WHOIS information. The purpose of this document is to build an object inventory to facilitate discussions of data objects included in Registration Data Access Protocol (RDAP) responses. Securing Routing Policy Specification Language (RPSL) Objects with Resource Public Key Infrastructure (RPKI) Signatures This document describes a method that allows parties to electronically sign Routing Policy Specification Language objects and validate such electronic signatures. This allows relying parties to detect accidental or malicious modifications of such objects. It also allows parties who run Internet Routing Registries or similar databases, but do not yet have authentication (based on Routing Policy System Security) of the maintainers of certain objects, to verify that the additions or modifications of such database objects are done by the legitimate holder(s) of the Internet resources mentioned in those objects. This document updates RFCs 2622 and 4012 to add the signature attribute to supported RPSL objects. A Format for Self-Published IP Geolocation Feeds This document records a format whereby a network operator can publish a mapping of IP address prefixes to simplified geolocation information, colloquially termed a "geolocation feed". Interested parties can poll and parse these feeds to update or merge with other geolocation data sources and procedures. This format intentionally only allows specifying coarse-level location. Some technical organizations operating networks that move from one conference location to the next have already experimentally published small geolocation feeds. This document describes a currently deployed format. At least one consumer (Google) has incorporated these feeds into a geolocation data pipeline, and a significant number of ISPs are using it to inform them where their prefixes should be geolocated. Temporary Address Extensions for Stateless Address Autoconfiguration in IPv6 This document describes an extension to IPv6 Stateless Address Autoconfiguration that causes hosts to generate temporary addresses with randomized interface identifiers for each prefix advertised with autoconfiguration enabled. Changing addresses over time limits the window of time during which eavesdroppers and other information collectors may trivially perform address-based network-activity correlation when the same address is employed for multiple transactions by the same host. Additionally, it reduces the window of exposure of a host as being accessible via an address that becomes revealed as a result of active communication. This document obsoletes RFC 4941. JSON Responses for the Registration Data Access Protocol (RDAP) This document describes JSON data structures representing registration information maintained by Regional Internet Registries (RIRs) and Domain Name Registries (DNRs). These data structures are used to form Registration Data Access Protocol (RDAP) query responses. This document obsoletes RFC 7483. HTTP Caching The Hypertext Transfer Protocol (HTTP) is a stateless application-level protocol for distributed, collaborative, hypertext information systems. This document defines HTTP caches and the associated header fields that control cache behavior or indicate cacheable response messages. This document obsoletes RFC 7234. Finding and Using Geofeed Data This document specifies how to augment the Routing Policy Specification Language (RPSL) inetnum: class to refer specifically to geofeed comma-separated values (CSV) data files and describes an optional scheme that uses the Resource Public Key Infrastructure (RPKI) to authenticate the geofeed data files. This document obsoletes RFC 9092. Registration Data Access Protocol (RDAP) Extension for Geofeed Data This document defines a new Registration Data Access Protocol (RDAP) extension, "geofeed1", for indicating that an RDAP server hosts geofeed URLs for its IP network objects. It also defines a new media type and a new link relation type for the associated link objects included in responses. RIPE Database Documentation RIPE NCC Representation Of IP Routing Policies In A Routing Registry RIPE-181 Representation Of IP Routing Policies In The RIPE Database RIPE-081

ASN.1 Module This appendix provides an ASN.1 Module for the CMS content type used for the prefixlen file. CONTENT-TYPE is imported from the ASN.1 Module in . PrefixLengthsModule-2025 { iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1) pkcs9(9) smime(16) mod(0) 87 } DEFINITIONS IMPLICIT TAGS ::= BEGIN -- EXPORTS ALL -- IMPORTS CONTENT-TYPE FROM CryptographicMessageSyntax-2010 -- in [RFC6268] { iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1) pkcs-9(9) smime(16) modules(0) id-mod-cms-2009(58) } ; ContentSet CONTENT-TYPE ::= { ct-prefixlenCSVwithCRLF, ... } ct-prefixlenCSVwithCRLF CONTENT-TYPE ::= { TYPE UTF8String IDENTIFIED BY id-ct-prefixlenCSVwithCRLF } id-ct-prefixlenCSVwithCRLF OBJECT IDENTIFIER ::= { iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1) pkcs-9(9) smime(16) ct(1) 57 } END

Example This appendix provides an example, including a trust anchor, a Certificate Revocation List (CRL) signed by the trust anchor, a CA certificate subordinate to the trust anchor, a CRL signed by the CA, an end-entity certificate subordinate to the CA for signing the prefixlen file, and a detached signature. The trust anchor is represented by a self-signed certificate. As usual in the RPKI, the trust anchor has authority over all IPv4 address blocks, all IPv6 address blocks, and all Autonomous System (AS) numbers. -----BEGIN CERTIFICATE----- MIIEQTCCAymgAwIBAgIUEggycNoFVRjAuN/Fw7URu0DEZNAwDQYJKoZIhvcNAQEL BQAwFTETMBEGA1UEAxMKZXhhbXBsZS10YTAeFw0yMzA5MTkyMDMzMzlaFw0zMzA5 MTYyMDMzMzlaMBUxEzARBgNVBAMTCmV4YW1wbGUtdGEwggEiMA0GCSqGSIb3DQEB AQUAA4IBDwAwggEKAoIBAQDQprR+g/i4JyObVURTp1JpGM23vGPyE5fDKFPqV7rw M1Amm7cnew66U02IzV0X5oiv5nSGfRX5UxsbR+vwPBMceQyDgS5lexFiv4fB/Vjf DT2qX/UjsLL9QOeaSOh7ToJSLjmtpa0D9iz7ful3hdxRjpMMZiE/reX9/ymdpW/E dg0F6+T9WGZE1miPeIjl5OZwnmLHCftkN/aaYk1iPNjNniHYIOjC1jSpABmoZyTj sgrwLE2F1fIRkVkwASqToq/D5v9voXaYYaXUNJb4H/5wenRuvT5O/n6PXh70rMQy F5yzLs96ytxqg5gGX9kabVnvxFU8nHfPa0rhlwfTJnljAgMBAAGjggGHMIIBgzAd BgNVHQ4EFgQUwL1SXb7SeLIW7LOjQ5XSBguZCDIwHwYDVR0jBBgwFoAUwL1SXb7S eLIW7LOjQ5XSBguZCDIwDwYDVR0TAQH/BAUwAwEB/zAOBgNVHQ8BAf8EBAMCAQYw GAYDVR0gAQH/BA4wDDAKBggrBgEFBQcOAjCBuQYIKwYBBQUHAQsEgawwgakwPgYI KwYBBQUHMAqGMnJzeW5jOi8vcnBraS5leGFtcGxlLm5ldC9yZXBvc2l0b3J5L2V4 YW1wbGUtdGEubWZ0MDUGCCsGAQUFBzANhilodHRwczovL3JyZHAuZXhhbXBsZS5u ZXQvbm90aWZpY2F0aW9uLnhtbDAwBggrBgEFBQcwBYYkcnN5bmM6Ly9ycGtpLmV4 YW1wbGUubmV0L3JlcG9zaXRvcnkvMCcGCCsGAQUFBwEHAQH/BBgwFjAJBAIAATAD AwEAMAkEAgACMAMDAQAwIQYIKwYBBQUHAQgBAf8EEjAQoA4wDDAKAgEAAgUA//// /zANBgkqhkiG9w0BAQsFAAOCAQEAa9eLY9QAmnlZOIyOzbpta5wqcOUQV/yR7o/0 1zkEZaSavKBt19lMK6AXZurx1T5jyjIwG7bEtZZThjtH2m80V5kc2tsFjSq/yp7N JBclMHVd3tXse9If3nXYF4bxRIcir1lXlAbYN+Eo1U3i5qJO+fxouzt7Merk2Dih nsenTeXKzN7tfmuCYZZHCC8viCoJWdH+o1uRM4TiQApZsUJ8sF4TABrrRJmA/Ed5 v0CTBbgqTx7yg0+VarFLPdnjYgtpoCJqwE2C1UpX15rZSaLVuGXtbwXd/cHEg5vF W6QTsMeMQFEUa6hkicDGtxLTUdhckBgmCGoF2nlZii5f1BTWAg== -----END CERTIFICATE----- The CRL issued by the trust anchor. -----BEGIN X509 CRL----- MIIBjjB4AgEBMA0GCSqGSIb3DQEBCwUAMBUxEzARBgNVBAMTCmV4YW1wbGUtdGEX DTI2MDUwNzIxMjI0OVoXDTI2MDYwNjIxMjI0OVqgLzAtMB8GA1UdIwQYMBaAFMC9 Ul2+0niyFuyzo0OV0gYLmQgyMAoGA1UdFAQDAgEMMA0GCSqGSIb3DQEBCwUAA4IB AQCkHXyCcQHejmVdHOL5Diafa3ys4HTb2eRqeNaMzwfY6T1D26hX6XuUyu0C7LV2 OThlAL8JWiN2afgfs5juBAWdauwY5YSKAvQpXidFeCIXpSWLHmk545p7t9og6qpy 840l+N+J2WnP9iGNCqgKG06CiRAoPtZZQCqqLZVcrELtDAOFNmZF0Bf+cE2SmsZO 8N/ab/fw05Ptm/IBqN3j+ekaILELFRWUGPaAXMimWYn6sNmzYdihUn2fNff294PZ Mygxfw8dpWlA01QQt8d9V+3NklyOKEB3X+X12eA4KYaVDCt4USWMlnlETNO3XwDe Cg5BBjoh5EtXzsNWf2ipZTNb -----END X509 CRL----- The CA certificate is issued by the trust anchor. This certificate grants authority over one IPv4 address block (192.0.2.0/24), one IPv6 address block(2001:db8::/32), and two AS numbers (64496 and 64497). -----BEGIN CERTIFICATE----- MIIE+zCCA+OgAwIBAgIUcyCzS10hdfG65kbRq7toQAvRDMIwDQYJKoZIhvcNAQEL BQAwFTETMBEGA1UEAxMKZXhhbXBsZS10YTAeFw0yNjA1MDcyMTIyNDlaFw0yNzA1 MDcyMTIyNDlaMDMxMTAvBgNVBAMTKDNBQ0UyQ0VGNEZCMjFCN0QxMUUzRTE4NEVG QzFFMjk3QjM3Nzg2NDIwggEiMA0GCSqGSIb3DQEBAQUAA4IBDwAwggEKAoIBAQDc zz1qwTxC2ocw5rqp8ktm2XyYkl8riBVuqlXwfefTxsR2YFpgz9vkYUd5Az9EVEG7 6wGIyZbtmhK63eEeaqbKz2GHub467498BXeVrYysO+YuIGgCEYKznNDZ4j5aaDbo j5+4/z0Qvv6HEsxQd0f8br6lKJwgeRM6+fm7796HNPB0aqD7Zj9NRCLXjbB0DCgJ liH6rXMKR86ofgll9V2mRjesvhdKYgkGbOif9rvxVpLJ/6zdru5CE9yeuJZ59l+n YH/r6PzdJ4Q7yKrJX8qD6A60j4+biaU4MQ72KpsjhQNTTqF/HRwi0N54GDaknEwE TnJQHgLJDYqww9yKWtjjAgMBAAGjggIjMIICHzAdBgNVHQ4EFgQUOs4s70+yG30R 4+GE78Hil7N3hkIwHwYDVR0jBBgwFoAUwL1SXb7SeLIW7LOjQ5XSBguZCDIwDwYD VR0TAQH/BAUwAwEB/zAOBgNVHQ8BAf8EBAMCAQYwGAYDVR0gAQH/BA4wDDAKBggr BgEFBQcOAjBDBgNVHR8EPDA6MDigNqA0hjJyc3luYzovL3Jwa2kuZXhhbXBsZS5u ZXQvcmVwb3NpdG9yeS9leGFtcGxlLXRhLmNybDBOBggrBgEFBQcBAQRCMEAwPgYI KwYBBQUHMAKGMnJzeW5jOi8vcnBraS5leGFtcGxlLm5ldC9yZXBvc2l0b3J5L2V4 YW1wbGUtdGEuY2VyMIG5BggrBgEFBQcBCwSBrDCBqTA+BggrBgEFBQcwCoYycnN5 bmM6Ly9ycGtpLmV4YW1wbGUubmV0L3JlcG9zaXRvcnkvZXhhbXBsZS1jYS5tZnQw NQYIKwYBBQUHMA2GKWh0dHBzOi8vcnJkcC5leGFtcGxlLm5ldC9ub3RpZmljYXRp b24ueG1sMDAGCCsGAQUFBzAFhiRyc3luYzovL3Jwa2kuZXhhbXBsZS5uZXQvcmVw b3NpdG9yeS8wLgYIKwYBBQUHAQcBAf8EHzAdMAwEAgABMAYDBADAAAIwDQQCAAIw BwMFACABDbgwIQYIKwYBBQUHAQgBAf8EEjAQoA4wDDAKAgMA+/ACAwD78TANBgkq hkiG9w0BAQsFAAOCAQEAipx10/ZrY11NYH+iVRtq32hAFGGaXysLWrjFVYd05+25 2nPtZYPmtLRf7TWMSwF27AkGPzvonjsRF2a7wdMAPDIW2nKctmDS1nFGWw+6vXyN Di+jhwHm7+FyFWh3u2ilzop+o6ecUiCF8rkE22TWHRkBJforN0eqUjJi0R/o4oaB q9sZs+Jr3vTmelRYjvP8Eej3AWRm+rilbP8yW3OOvV3sTvgJc4DmbFNJ2LBJ+cLx 1fjl+Wf/YHPo2kHw8f1TJsgXSI6kYBUradIyXIW1HGrWdiKiY+oXp+jVbf8cMvp/ KkLf1UqqCjgdu3GGQuukKjbNHeJPMuHmVw5Qa3iGzg== -----END CERTIFICATE----- The CRL issued by the CA. -----BEGIN X509 CRL----- MIIBrTCBlgIBATANBgkqhkiG9w0BAQsFADAzMTEwLwYDVQQDEygzQUNFMkNFRjRG QjIxQjdEMTFFM0UxODRFRkMxRTI5N0IzNzc4NjQyFw0yNjA1MDcyMTIyNDlaFw0y NjA2MDYyMTIyNDlaoC8wLTAfBgNVHSMEGDAWgBQ6zizvT7IbfRHj4YTvweKXs3eG QjAKBgNVHRQEAwIBATANBgkqhkiG9w0BAQsFAAOCAQEAFEEWr/QvDz2efRDS9mep GSpNS2QPbeV7Oz+rO5sZAIxrpuBZObe0NRlZaMamM0X+lSgKnEai2Ep5Pm4NzG6M Z1dHSrp196l65o0CTiPK0r4IqEUfY1Q6tkzXzc/6c9kUxMerE1saY/OlN29yYJ4F IDHrczvK5y1ddK8g3FB7fNjti4RCFAec8RsyizemDwS4JLd1R3y1+olJ5OH6Gvqq uMTSAJHl4LL5DeAZm3WLzL49PJWcaKoNe0oAPDdEalW5GXlAMsbQw9W8mOvBKotP 5Q9k8VVXaILSFn2+AzPKX7fQXoA954KMVnDAgN0r8Fa743J7TlbFbk+l5+V/+88f cA== -----END X509 CRL----- The end-entity certificate is issued by the CA. This certificate grants signature authority for one IPv4 address block (192.0.2.0/24). Signature authority for the IPv6 address block and the AS numbers is not needed for the prefixlen file that will be signed, so these items are not included in the end-entity certificate. -----BEGIN CERTIFICATE----- MIIEVjCCAz6gAwIBAgIUJ605QIPX8rW5m4Zwx3WyuW7hZvswDQYJKoZIhvcNAQEL BQAwMzExMC8GA1UEAxMoM0FDRTJDRUY0RkIyMUI3RDExRTNFMTg0RUZDMUUyOTdC Mzc3ODY0MjAeFw0yNjA1MDcyMTIyNDlaFw0yNzAzMDMyMTIyNDlaMDMxMTAvBgNV BAMTKDkxNDY1MkEzQkQ1MUMxNDQyNjAxOTg4ODlGNUM0NUFCRjA1M0ExODcwggEi MA0GCSqGSIb3DQEBAQUAA4IBDwAwggEKAoIBAQCycTQrOb/qB2W3i3Ki8PhA/DEW yii2TgGo9pgCwO9lsIRI6Zb/k+aSiWWP9kSczlcQgtPCVwr62hTQZCIowBN0BL0c K0/5k1imJdi5qdM3nvKswM8CnoR11vB8pQFwruZmr5xphXRvE+mzuJVLgu2V1upm BXuWloeymudh6WWJ+GDjwPXO3RiXBejBrOFNXhaFLe08y4DPfr/S/tXJOBm7QzQp tmbPLYtGfprYu45liFFqqP94UeLpISfXd36AKGzqTFCcc3EW9l5UFE1MFLlnoEog qtoLoKABt0IkOFGKeC/EgeaBdWLe469ddC9rQft5w6g6cmxG+aYDdIEB34zrAgMB AAGjggFgMIIBXDAdBgNVHQ4EFgQUkUZSo71RwUQmAZiIn1xFq/BToYcwHwYDVR0j BBgwFoAUOs4s70+yG30R4+GE78Hil7N3hkIwDgYDVR0PAQH/BAQDAgeAMBgGA1Ud IAEB/wQOMAwwCgYIKwYBBQUHDgIwYQYDVR0fBFowWDBWoFSgUoZQcnN5bmM6Ly9y cGtpLmV4YW1wbGUubmV0L3JlcG9zaXRvcnkvM0FDRTJDRUY0RkIyMUI3RDExRTNF MTg0RUZDMUUyOTdCMzc3ODY0Mi5jcmwwbAYIKwYBBQUHAQEEYDBeMFwGCCsGAQUF BzAChlByc3luYzovL3Jwa2kuZXhhbXBsZS5uZXQvcmVwb3NpdG9yeS8zQUNFMkNF RjRGQjIxQjdEMTFFM0UxODRFRkMxRTI5N0IzNzc4NjQyLmNlcjAfBggrBgEFBQcB BwEB/wQQMA4wDAQCAAEwBgMEAMAAAjANBgkqhkiG9w0BAQsFAAOCAQEAUIykBaqY nR/U+AXYzCqRbMqdygFY9R11fiNQubpkf5kEYHFxTut0CZLz9dToxuHRDLbPhjJv Ci3cDkb2ICy1Fdcit5oi9jFl1MD/sFa4l/FWGM07PhgKY+Isz3DXEw9furF7Al3I gbB0and5HQrvQbO6AnqixSYDffANsnZssojMzlHJIA9OLHIuhGZ66t+yh2VclhwV 7JdS+0EdyA0npIrTGyp//pD5vrigF04y+J4Y61jFXfmbWZbNJF/bMzFeBxD2PKaE uwixf65s3yI0JDjBbXjUtUhqyty0IZqV2HcuWU7MKH9Qc/wvrJDd4K4xTbkWWYgA ql7bgmJTHpW2Gw== -----END CERTIFICATE----- The end-entity certificate is displayed below in detail. For brevity, the other two certificates are not. 0 1110: SEQUENCE { 4 830: SEQUENCE { 8 3: [0] { 10 1: INTEGER 2 : } 13 20: INTEGER : 27 AD 39 40 83 D7 F2 B5 B9 9B 86 70 C7 75 B2 B9 : 6E E1 66 FB 35 13: SEQUENCE { 37 9: OBJECT IDENTIFIER : sha256WithRSAEncryption (1 2 840 113549 1 1 11) 48 0: NULL : } 50 51: SEQUENCE { 52 49: SET { 54 47: SEQUENCE { 56 3: OBJECT IDENTIFIER commonName (2 5 4 3) 61 40: PrintableString : '3ACE2CEF4FB21B7D11E3E184EFC1E297B3778642' : } : } : } 103 30: SEQUENCE { 105 13: UTCTime 07/05/2026 21:22:49 GMT 120 13: UTCTime 03/03/2027 21:22:49 GMT : } 135 51: SEQUENCE { 137 49: SET { 139 47: SEQUENCE { 141 3: OBJECT IDENTIFIER commonName (2 5 4 3) 146 40: PrintableString : '914652A3BD51C144260198889F5C45ABF053A187' : } : } : } 188 290: SEQUENCE { 192 13: SEQUENCE { 194 9: OBJECT IDENTIFIER : rsaEncryption (1 2 840 113549 1 1 1) 205 0: NULL : } 207 271: BIT STRING, encapsulates { 212 266: SEQUENCE { 216 257: INTEGER : 00 B2 71 34 2B 39 BF EA 07 65 B7 8B 72 A2 F0 F8 : 40 FC 31 16 CA 28 B6 4E 01 A8 F6 98 02 C0 EF 65 : B0 84 48 E9 96 FF 93 E6 92 89 65 8F F6 44 9C CE : 57 10 82 D3 C2 57 0A FA DA 14 D0 64 22 28 C0 13 : 74 04 BD 1C 2B 4F F9 93 58 A6 25 D8 B9 A9 D3 37 : 9E F2 AC C0 CF 02 9E 84 75 D6 F0 7C A5 01 70 AE : E6 66 AF 9C 69 85 74 6F 13 E9 B3 B8 95 4B 82 ED : 95 D6 EA 66 05 7B 96 96 87 B2 9A E7 61 E9 65 89 : F8 60 E3 C0 F5 CE DD 18 97 05 E8 C1 AC E1 4D 5E : 16 85 2D ED 3C CB 80 CF 7E BF D2 FE D5 C9 38 19 : BB 43 34 29 B6 66 CF 2D 8B 46 7E 9A D8 BB 8E 65 : 88 51 6A A8 FF 78 51 E2 E9 21 27 D7 77 7E 80 28 : 6C EA 4C 50 9C 73 71 16 F6 5E 54 14 4D 4C 14 B9 : 67 A0 4A 20 AA DA 0B A0 A0 01 B7 42 24 38 51 8A : 78 2F C4 81 E6 81 75 62 DE E3 AF 5D 74 2F 6B 41 : FB 79 C3 A8 3A 72 6C 46 F9 A6 03 74 81 01 DF 8C : EB 477 3: INTEGER 65537 : } : } : } 482 352: [3] { 486 348: SEQUENCE { 490 29: SEQUENCE { 492 3: OBJECT IDENTIFIER : subjectKeyIdentifier (2 5 29 14) 497 22: OCTET STRING, encapsulates { 499 20: OCTET STRING : 91 46 52 A3 BD 51 C1 44 26 01 98 88 9F 5C 45 AB : F0 53 A1 87 : } : } 521 31: SEQUENCE { 523 3: OBJECT IDENTIFIER : authorityKeyIdentifier (2 5 29 35) 528 24: OCTET STRING, encapsulates { 530 22: SEQUENCE { 532 20: [0] : 3A CE 2C EF 4F B2 1B 7D 11 E3 E1 84 EF C1 E2 97 : B3 77 86 42 : } : } : } 554 14: SEQUENCE { 556 3: OBJECT IDENTIFIER keyUsage (2 5 29 15) 561 1: BOOLEAN TRUE 564 4: OCTET STRING, encapsulates { 566 2: BIT STRING 7 unused bits : '1'B (bit 0) : } : } 570 24: SEQUENCE { 572 3: OBJECT IDENTIFIER certificatePolicies (2 5 29 32) 577 1: BOOLEAN TRUE 580 14: OCTET STRING, encapsulates { 582 12: SEQUENCE { 584 10: SEQUENCE { 586 8: OBJECT IDENTIFIER : resourceCertificatePolicy (1 3 6 1 5 5 7 14 2) : } : } : } : } 596 97: SEQUENCE { 598 3: OBJECT IDENTIFIER : cRLDistributionPoints (2 5 29 31) 603 90: OCTET STRING, encapsulates { 605 88: SEQUENCE { 607 86: SEQUENCE { 609 84: [0] { 611 82: [0] { 613 80: [6] : 'rsync://rpki.example.net/repository/3ACE' : '2CEF4FB21B7D11E3E184EFC1E297B3778642.crl' : } : } : } : } : } : } 695 108: SEQUENCE { 697 8: OBJECT IDENTIFIER : authorityInfoAccess (1 3 6 1 5 5 7 1 1) 707 96: OCTET STRING, encapsulates { 709 94: SEQUENCE { 711 92: SEQUENCE { 713 8: OBJECT IDENTIFIER : caIssuers (1 3 6 1 5 5 7 48 2) 723 80: [6] : 'rsync://rpki.example.net/repository/3ACE' : '2CEF4FB21B7D11E3E184EFC1E297B3778642.cer' : } : } : } : } 805 31: SEQUENCE { 807 8: OBJECT IDENTIFIER : ipAddrBlocks (1 3 6 1 5 5 7 1 7) 817 1: BOOLEAN TRUE 820 16: OCTET STRING, encapsulates { 822 14: SEQUENCE { 824 12: SEQUENCE { 826 2: OCTET STRING 00 01 830 6: SEQUENCE { 832 4: BIT STRING : '010000000000000000000011'B : } : } : } : } : } : } : } : } 838 13: SEQUENCE { 840 9: OBJECT IDENTIFIER : sha256WithRSAEncryption (1 2 840 113549 1 1 11) 851 0: NULL : } 853 257: BIT STRING : 50 8C A4 05 AA 98 9D 1F D4 F8 05 D8 CC 2A 91 6C : CA 9D CA 01 58 F5 1D 75 7E 23 50 B9 BA 64 7F 99 : 04 60 71 71 4E EB 74 09 92 F3 F5 D4 E8 C6 E1 D1 : 0C B6 CF 86 32 6F 0A 2D DC 0E 46 F6 20 2C B5 15 : D7 22 B7 9A 22 F6 31 65 D4 C0 FF B0 56 B8 97 F1 : 56 18 CD 3B 3E 18 0A 63 E2 2C CF 70 D7 13 0F 5F : BA B1 7B 02 5D C8 81 B0 74 6A 77 79 1D 0A EF 41 : B3 BA 02 7A A2 C5 26 03 7D F0 0D B2 76 6C B2 88 : CC CE 51 C9 20 0F 4E 2C 72 2E 84 66 7A EA DF B2 : 87 65 5C 96 1C 15 EC 97 52 FB 41 1D C8 0D 27 A4 : 8A D3 1B 2A 7F FE 90 F9 BE B8 A0 17 4E 32 F8 9E : 18 EB 58 C5 5D F9 9B 59 96 CD 24 5F DB 33 31 5E : 07 10 F6 3C A6 84 BB 08 B1 7F AE 6C DF 22 34 24 : 38 C1 6D 78 D4 B5 48 6A CA DC B4 21 9A 95 D8 77 : 2E 59 4E CC 28 7F 50 73 FC 2F AC 90 DD E0 AE 31 : 4D B9 16 59 88 00 AA 5E DB 82 62 53 1E 95 B6 1B : } To allow reproduction of the signature results, the end-entity private key is provided. For brevity, the other two private keys are not. -----BEGIN RSA PRIVATE KEY----- MIIEpQIBAAKCAQEAsnE0Kzm/6gdlt4tyovD4QPwxFsootk4BqPaYAsDvZbCESOmW /5Pmkollj/ZEnM5XEILTwlcK+toU0GQiKMATdAS9HCtP+ZNYpiXYuanTN57yrMDP Ap6EddbwfKUBcK7mZq+caYV0bxPps7iVS4LtldbqZgV7lpaHsprnYellifhg48D1 zt0YlwXowazhTV4WhS3tPMuAz36/0v7VyTgZu0M0KbZmzy2LRn6a2LuOZYhRaqj/ eFHi6SEn13d+gChs6kxQnHNxFvZeVBRNTBS5Z6BKIKraC6CgAbdCJDhRingvxIHm gXVi3uOvXXQva0H7ecOoOnJsRvmmA3SBAd+M6wIDAQABAoIBAQCyB0FeMuKm8bRo 18aKjFGSPEoZi53srIz5bvUgIi92TBLez7ZnzL6Iym26oJ+5th+lCHGO/dqlhXio pI50C5Yc9TFbblb/ECOsuCuuqKFjZ8CD3GVsHozXKJeMM+/o5YZXQrORj6UnwT0z ol/JE5pIGUCIgsXX6tz9s5BP3lUAvVQHsv6+vEVKLxQ3wj/1vIL8O/CN036EV0GJ mpkwmygPjfECT9wbWo0yn3jxJb36+M/QjjUP28oNIVn/IKoPZRXnqchEbuuCJ651 IsaFSqtiThm4WZtvCH/IDq+6/dcMucmTjIRcYwW7fdHfjplllVPve9c/OmpWEQvF t3ArWUt5AoGBANs4764yHxo4mctLIE7G7l/tf9bP4KKUiYw4R4ByEocuqMC4yhmt MPCfOFLOQet71OWCkjP2L/7EKUe9yx7G5KmxAHY6jOjvcRkvGsl6lWFOsQ8p126M Y9hmGzMOjtsdhAiMmOWKzjvm4WqfMgghQe+PnjjSVkgTt+7BxpIuGBAvAoGBANBg 26FF5cDLpixOd3Za1YXsOgguwCaw3Plvi7vUZRpa/zBMELEtyOebfakkIRWNm07l nE+lAZwxm+29PTD0nqCFE91teyzjnQaLO5kkAdJiFuVV3icLOGo399FrnJbKensm FGSli+3KxQhCNIJJfgWzq4bE0ioAMjdGbYXzIYQFAoGBAM6tuDJ36KDU+hIS6wu6 O2TPSfZhF/zPo3pCWQ78/QDb+Zdw4IEiqoBA7F4NPVLg9Y/H8UTx9r/veqe7hPOo Ok7NpIzSmKTHkc5XfZ60Zn9OLFoKbaQ40a1kXoJdWEu2YROaUlAe9F6/Rog6PHYz vLE5qscRbu0XQhLkN+z7bg5bAoGBAKDsbDEb/dbqbyaAYpmwhH2sdRSkphg7Niwc DNm9qWa1J6Zw1+M87I6Q8naRREuU1IAVqqWHVLr/ROBQ6NTJ1Uc5/qFeT2XXUgkf taMKv61tuyjZK3sTmznMh0HfzUpWjEhWnCEuB+ZYVdmO52ZGw2A75RdrILL2+9Dc PvDXVubRAoGAdqXeSWoLxuzZXzl8rsaKrQsTYaXnOWaZieU1SL5vVe8nK257UDqZ E3ng2j5XPTUWli+aNGFEJGRoNtcQvO60O/sFZUhu52sqq9mWVYZNh1TB5aP8X+pV iFcZOLUvQEcN6PA+YQK5FU11rAI1M0Gm5RDnVnUl0L2xfCYxb7FzV6Y= -----END RSA PRIVATE KEY----- Signing of "192.0.2.0/24,32,1" (terminated by CR and LF), yields the following detached CMS signature. # RPKI Signature: 192.0.2.0 - 192.0.2.255 # MIIGQAYJKoZIhvcNAQcCoIIGMTCCBi0CAQMxDTALBglghkgBZQMEAgEwDQYLKoZ # IhvcNAQkQATmgggRaMIIEVjCCAz6gAwIBAgIUJ605QIPX8rW5m4Zwx3WyuW7hZv # swDQYJKoZIhvcNAQELBQAwMzExMC8GA1UEAxMoM0FDRTJDRUY0RkIyMUI3RDExR # TNFMTg0RUZDMUUyOTdCMzc3ODY0MjAeFw0yNjA1MDcyMTIyNDlaFw0yNzAzMDMy # MTIyNDlaMDMxMTAvBgNVBAMTKDkxNDY1MkEzQkQ1MUMxNDQyNjAxOTg4ODlGNUM # 0NUFCRjA1M0ExODcwggEiMA0GCSqGSIb3DQEBAQUAA4IBDwAwggEKAoIBAQCycT # QrOb/qB2W3i3Ki8PhA/DEWyii2TgGo9pgCwO9lsIRI6Zb/k+aSiWWP9kSczlcQg # tPCVwr62hTQZCIowBN0BL0cK0/5k1imJdi5qdM3nvKswM8CnoR11vB8pQFwruZm # r5xphXRvE+mzuJVLgu2V1upmBXuWloeymudh6WWJ+GDjwPXO3RiXBejBrOFNXha # FLe08y4DPfr/S/tXJOBm7QzQptmbPLYtGfprYu45liFFqqP94UeLpISfXd36AKG # zqTFCcc3EW9l5UFE1MFLlnoEogqtoLoKABt0IkOFGKeC/EgeaBdWLe469ddC9rQ # ft5w6g6cmxG+aYDdIEB34zrAgMBAAGjggFgMIIBXDAdBgNVHQ4EFgQUkUZSo71R # wUQmAZiIn1xFq/BToYcwHwYDVR0jBBgwFoAUOs4s70+yG30R4+GE78Hil7N3hkI # wDgYDVR0PAQH/BAQDAgeAMBgGA1UdIAEB/wQOMAwwCgYIKwYBBQUHDgIwYQYDVR # 0fBFowWDBWoFSgUoZQcnN5bmM6Ly9ycGtpLmV4YW1wbGUubmV0L3JlcG9zaXRvc # nkvM0FDRTJDRUY0RkIyMUI3RDExRTNFMTg0RUZDMUUyOTdCMzc3ODY0Mi5jcmww # bAYIKwYBBQUHAQEEYDBeMFwGCCsGAQUFBzAChlByc3luYzovL3Jwa2kuZXhhbXB # sZS5uZXQvcmVwb3NpdG9yeS8zQUNFMkNFRjRGQjIxQjdEMTFFM0UxODRFRkMxRT # I5N0IzNzc4NjQyLmNlcjAfBggrBgEFBQcBBwEB/wQQMA4wDAQCAAEwBgMEAMAAA # jANBgkqhkiG9w0BAQsFAAOCAQEAUIykBaqYnR/U+AXYzCqRbMqdygFY9R11fiNQ # ubpkf5kEYHFxTut0CZLz9dToxuHRDLbPhjJvCi3cDkb2ICy1Fdcit5oi9jFl1MD # /sFa4l/FWGM07PhgKY+Isz3DXEw9furF7Al3IgbB0and5HQrvQbO6AnqixSYDff # ANsnZssojMzlHJIA9OLHIuhGZ66t+yh2VclhwV7JdS+0EdyA0npIrTGyp//pD5v # rigF04y+J4Y61jFXfmbWZbNJF/bMzFeBxD2PKaEuwixf65s3yI0JDjBbXjUtUhq # yty0IZqV2HcuWU7MKH9Qc/wvrJDd4K4xTbkWWYgAql7bgmJTHpW2GzGCAaowggG # mAgEDgBSRRlKjvVHBRCYBmIifXEWr8FOhhzALBglghkgBZQMEAgGgazAaBgkqhk # iG9w0BCQMxDQYLKoZIhvcNAQkQATkwHAYJKoZIhvcNAQkFMQ8XDTI2MDUwNzIxM # jI0OVowLwYJKoZIhvcNAQkEMSIEIGMBdMKw5mjZYL9qP4ivwgMt8g2+qEO0+Dcn # N5vQO1bNMA0GCSqGSIb3DQEBAQUABIIBAKzRicWBpSyN5nw39eDNfVai2H1mO0n # APgZUmVF/vgSCWtR0da1iZots4qwn0XwvvIgu5eZ7edhn9axLXhjTAOQajT4cOw # 9+raD7+SYdBIAUgZpuFy3Olnu4HykCd8Ub44lPfZVG1lF1LeN248+rWgozpE7xz # Dv5G83OslbvVzGXaVShJM4fsDfpkpKoQ4LszlBeqguU2yTm3XWVjkxH7VJvTtIT # SzO3jAqwqnCjfu3mnxCoz7LKES4DPZERsFoJv1zyDdHIXjPnfZuTBjjCOubjaQx # rRwgZtQ8Ljz3gpz1VzL9mKAv0pUzcyxtQfakHwdYtxyO33z2InljtTFJCroI= # End Signature: 192.0.2.0 - 192.0.2.255

Acknowledgments Thanks to the authors of and and the folk they acknowledge from whom ideas and text have been liberally expropriated. Thanks to for providing useful feedback on the document.