PCE Working Group A. Wang Internet-Draft China Telecom Intended status: Standards Track B. Khasanov Expires: April 23, 2021 S. Fang R. Tan Huawei Technologies,Co.,Ltd C. Zhu ZTE Corporation October 20, 2020 PCEP Extension for Native IP Network draft-ietf-pce-pcep-extension-native-ip-09 Abstract This document defines the Path Computation Element Communication Protocol (PCEP) extension for Central Control Dynamic Routing (CCDR) based application in Native IP network. The scenario and framework of CCDR in native IP is described in [RFC8735] and [I-D.ietf-teas-pce-native-ip]. This draft describes the key information that is transferred between Path Computation Element (PCE) and Path Computation Clients (PCC) to accomplish the End to End (E2E) traffic assurance in Native IP network under central control mode. 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 April 23, 2021. Copyright Notice Copyright (c) 2020 IETF Trust and the persons identified as the document authors. All rights reserved. Wang, et al. Expires April 23, 2021 [Page 1] Internet-Draft PCEP Extension for Native IP Network October 2020 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 2. Conventions used in this document . . . . . . . . . . . . . . 3 3. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3 4. Capability Advertisemnt . . . . . . . . . . . . . . . . . . . 3 4.1. Open message . . . . . . . . . . . . . . . . . . . . . . 3 5. PCEP messages . . . . . . . . . . . . . . . . . . . . . . . . 4 5.1. The PCInitiate message . . . . . . . . . . . . . . . . . 4 5.2. The PCRpt message . . . . . . . . . . . . . . . . . . . . 5 6. PCECC Native IP TE Procedures . . . . . . . . . . . . . . . . 6 6.1. BGP Session Establishment Procedures . . . . . . . . . . 6 6.2. Explicit Route Establish Procedures . . . . . . . . . . . 9 6.3. BGP Prefix Advertisement Procedures . . . . . . . . . . . 12 7. New PCEP Objects . . . . . . . . . . . . . . . . . . . . . . 13 7.1. CCI Object . . . . . . . . . . . . . . . . . . . . . . . 13 7.2. BGP Peer Info Object . . . . . . . . . . . . . . . . . . 14 7.3. Explicit Peer Route Object . . . . . . . . . . . . . . . 17 7.4. Peer Prefix Association Object . . . . . . . . . . . . . 18 8. New Error-Types and Error-Values Defined . . . . . . . . . . 19 9. Management Consideration . . . . . . . . . . . . . . . . . . 20 10. Security Considerations . . . . . . . . . . . . . . . . . . . 21 11. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 21 11.1. PCEP Object Types . . . . . . . . . . . . . . . . . . . 21 12. Contributor . . . . . . . . . . . . . . . . . . . . . . . . . 21 13. Acknowledgement . . . . . . . . . . . . . . . . . . . . . . . 21 14. Normative References . . . . . . . . . . . . . . . . . . . . 22 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 23 1. Introduction Generally, Multiprotocol Label Switching Traffic Engineering (MPLS- TE) requires the corresponding network devices support Multiprotocol Label Switching (MPLS) or Resource ReSerVation Protocol (RSVP)/Label Distribution Protocol (LDP) technologies to assure the End-to-End (E2E) traffic performance. But in native IP network, there will be no such signaling protocol to synchronize the action among different network devices. It is necessary to use the central control mode Wang, et al. Expires April 23, 2021 [Page 2] Internet-Draft PCEP Extension for Native IP Network October 2020 that described in [RFC8283] to correlate the forwarding behavior among different network devices. Draft [I-D.ietf-teas-pce-native-ip] describes the architecture and solution philosophy for the E2E traffic assurance in Native IP network via Multi Border Gateway Protocol (BGP) solution. This draft describes the corresponding Path Computation Element Communication Protocol (PCEP) extensions to transfer the key information about BGP peer info, peer prefix association and the explicit peer route on on-path routers. 2. Conventions used in this document 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 [RFC2119] [RFC8174] when, and only when, they appear in all capitals, as shown here. 3. Terminology This document uses the following terms defined in [RFC5440]: PCE, PCEP The following terms are defined in this document: o CCDR: Central Control Dynamic Routing o E2E: End to End o BPI: BGP Peer Info o EPR: Explicit Peer Route o PPA: Peer Prefix Association o QoS: Quality of Service 4. Capability Advertisemnt 4.1. Open message During the PCEP Initialization Phase, PCEP Speakers (PCE or PCC) advertise their support of Native IP extensions. This document defines a new Path Setup Type (PST) [RFC8408] for Native-IP, as follows: o PST = TBD1: Path is a Native IP path as per [I-D.ietf-teas-pce-native-ip]. Wang, et al. Expires April 23, 2021 [Page 3] Internet-Draft PCEP Extension for Native IP Network October 2020 A PCEP speaker MUST indicate its support of the function described in this document by sending a PATH-SETUP-TYPE-CAPABILITY TLV in the OPEN object with this new PST included in the PST list. [I-D.ietf-pce-pcep-extension-for-pce-controller] defined the PCECC- CAPABILITY sub-TLV to exchange information about their PCECC capability. A new flag is defined in PCECC-CAPABILITY sub-TLV for Native IP. N (NATIVE-IP-TE-CAPABILITY - 1 bit - TBD2): If set to 1 by a PCEP speaker, it indicates that the PCEP speaker is capable for TE in Native IP network as specified in this document. The flag MUST be set by both the PCC and PCE in order to support this extension. 5. PCEP messages PCECC Native IP TE solution utilizing the existing PCE LSP Initate Request message(PCInitiate)[RFC8281], and PCE Report message(PCRpt) [RFC8281] to accomplish the multi BGP sessions establishment, end to end TE path deployment, and route prefixes advertisement among different BGP sessions. A new PST for Native-IP is used to indicate the path setup based on TE in Native IP networks. The extended PCInitiate message described in [I-D.ietf-pce-pcep-extension-for-pce-controller] is used to download or cleanup central controller's instructions (CCIs). [I-D.ietf-pce-pcep-extension-for-pce-controller] specify an object called CCI for the encoding of central controller's instructions. This document specify a new CCI object-type for Native IP. The PCEP messages are extended in this document to handle the PCECC operations for Native IP. Three new PCEP Objects (BGP Peer Info (BPI) Object, Explicit Peer Route (EPR) Object and Peer Prefix Association (PPA) Object) are defined in this document. Refer toSection 7 for detail object definitions. 5.1. The PCInitiate message The PCInitiate Message defined in [RFC8281] and extended in [I-D.ietf-pce-pcep-extension-for-pce-controller] is further extended to support Native-IP CCI. The format of the extended PCInitiate message is as follows: Wang, et al. Expires April 23, 2021 [Page 4] Internet-Draft PCEP Extension for Native IP Network October 2020 ::= Where: is defined in [RFC5440] ::= [] ::= (| | ) ::= ( )| ((||) ) ::= [] Where: is as per [I-D.ietf-pce-pcep-extension-for-pce-controller]. and are as per [RFC8281]. The LSP and SRP object is defined in [RFC8231]. When PCInitiate message is used create Native IP instructions, the SRP and CCI objects MUST be present. The error handling for missing SRP or CCI object is as per [I-D.ietf-pce-pcep-extension-for-pce-controller]. Further either one of BPI, EPR, or PPA object MUST be present. If none of them are present, the receiving PCC MUST send a PCErr message with Error- type=6 (Mandatory Object missing) and Error-value=TBD (Native IP object missing). To cleanup the SRP object must set the R (remove) bit. 5.2. The PCRpt message The PCRpt message is used to acknowledge the Native-IP instructions received from the central controller (PCE). The format of the PCRpt message is as follows: Wang, et al. Expires April 23, 2021 [Page 5] Internet-Draft PCEP Extension for Native IP Network October 2020 ::= Where: ::= [] ::= (| ) ::= [] ::= [] ( )| ((||) ) Where: is as per [RFC8231] and the LSP and SRP object are also defined in [RFC8231]. The error handling for missing CCI object is as per [I-D.ietf-pce-pcep-extension-for-pce-controller]. Further either one of BPI, EPR, or PPA object MUST be present. If none of them are present, the receiving PCE MUST send a PCErr message with Error- type=6 (Mandatory Object missing) and Error-value=TBD ( Native IP object missing). 6. PCECC Native IP TE Procedures The detail procedures for the TE in native IP environment are described in the following sections. 6.1. BGP Session Establishment Procedures The procedures for establishing the BGP session between two peers is shown below, using the PCInitiate and PCRpt message pair. The PCInitiate message should be sent to PCC which acts as BGP routers and route reflector. In the example in Figure 1, it should be sent to R1(M1), R3(M2 & M3) and R7(M4), when R3 acts as RR. When PCC receives the BPI and CCI object (with the R bit set to 0 in SRP object) in PCInitiate message, the PCC should try to establish the BGP session with the indicated Peer AS and Local/Peer IP address. Wang, et al. Expires April 23, 2021 [Page 6] Internet-Draft PCEP Extension for Native IP Network October 2020 When PCC creates successfully the BGP session that is indicated by the associated information, it should report the result via the PCRpt messages, with BPI object included, and the corresponding SRP and CCI object. When PCC receives this message with the R bit set to 1 in SRP object in PCInitiate message, the PCC should clear the BGP session that indicated by the BPI object. When PCC clears successfully the specified BGP session, it should report the result via the PCRpt message, with the BPI object included, and the corresponding SRP and CCI object. Wang, et al. Expires April 23, 2021 [Page 7] Internet-Draft PCEP Extension for Native IP Network October 2020 M2 PCInitiate Message: M3 PCInitiate Message: CC-ID=X3(Symbolic Path Name=Class A) CC-ID=X3(Symbolic Path Name=Class A) BPI Object(Local IP=R3_A, Peer IP=R1_A) BPI Object(Local IP=R3_A, Peer IP=R7_A) M2-R PCRpt Message: M3-R PCRpt Message: CC-ID=X3 CC-ID=X3 BPI Object(Local IP=R3_A, Peer IP=R1_A) BPI Object(Local IP=R3_A, Peer IP=R7_A) ^ ^ | | +------------------------------------^------------------+ | | | | +------------------+ M1 PCInitiate Message: +----------+ PCE +-----------+ CC-ID=X1(Symbolic Path Name=Class A) | | +--------^---------+ | BPI Object(Local IP=R1_A, Peer IP=R3_A) | | | | | | | | <------+ +-------------+ +---+ M1-R PCRpt Message: | | | | CC-ID=X1 | +v-+ | | BPI Object(Local IP=R1_A, Peer IP=R3_A +------------------+R3+-------------------+ | ) | +--+ | | | | | +v-+ +--+ +--+ +-v+ | |R1+----------+R5+----------+R6+---------+R7| | ++-+ +--+ +--+ +-++ | M4 PCInitiate Message: | | | CC-ID=X7(Symbolic Path Name=Class A) | | | BPI Object(Local IP=R7_A,Peer IP=R3_A) | +--+ +--+ | | +------------+R2+----------+R4+-----------+ | | M4-R PCRpt Message: | CC-ID=X7 <----------------------------------------------------+ BPI Object(Local IP=R3_A, Peer IP=R1_A) Figure 1: BGP Session Establishment Procedures(R3 act as RR) If the PCC cannot establish the BGP session that required by this object, it should report the error values with the newly defined error type(Error-type=TBD) and error value(Error-Value=01 or 02), which is indicated in Section 8 Wang, et al. Expires April 23, 2021 [Page 8] Internet-Draft PCEP Extension for Native IP Network October 2020 6.2. Explicit Route Establish Procedures The detail procedures for the explicit route establishment procedures is shown below, using PCInitiate and PCRpt message pair. The PCInitiate message should be sent to the on-path routers respectively. In the example, for explicit route from R1 to R7, the PCInitiate message should be sent to R1(M1), R2(M2) and R4(M3), as shown in Figure 2. For explicit route from R7 to R1, the PCInitiate message should be sent to R7(M1), R4(M2) and R2(M3), as shown in Figure 3.. When PCC receives the EPR and the CCI object (with the R bit set to 0 in SRP object) in PCInitiate message, the PCC should install the explicit route to the the peer. When PCC install successfully the explicit route to the peer, it should report the result via the PCRpt messages, with EPR object included, and the corresponding SRP and CCI object. When PCC receives the EPR and the CCI object with the R bit set to 1 in SRP object in PCInitiate message, the PCC should clear the explicit route to the peer that indicated by the EPR object. When PCC clear successfully the explicit route that indicated by this object, it should report the result via the PCRpt message, with the EPR object included, and the corresponding SRP and CCI object. Wang, et al. Expires April 23, 2021 [Page 9] Internet-Draft PCEP Extension for Native IP Network October 2020 +------------------+ M1 PCInitiate Message: +----------+ PCE +-----------+ CC-ID=X1(Symbolic Path Name=Class A) | +----^---^---^-----+ | EPR Object(Peer Address=R7_A | | | | | Next Hop=R2_A) | | | | | | | | | | M1-R PCRpt Message: <---------------+ | | | | CC-ID=X1 | | +v-+ | | EPR Object(Peer Address=R7_A +------------+ +---+R3+-------------------+ ) Next Hop=R2_A) | | +--+ | | | | | | +v-+ +--+ | | +--+ +-v+ |R1+------+R5++ +----------------+R6+----+R7| ++-+ +--+ | | +--+ +-++ | | | | M2 PCInitiate Message | +---+ +---+ | CC-ID=X2(Symbolic Path Name=Class A) | +v-+ | | +v-+ | EPR Object(Peer Address=R7_A +----------+R2+-+ +--------+R4+-----------+ Next Hop=R4_A) | | | | M2-R PCRpt Message | | CC-ID=X2(Symbolic Path Name=Class A) <----------------------+ | EPR Object(Peer Address=R7_A | Next Hop=R4_A) | v M3 PCInitiate Message CC-ID=X4(Symbolic Path Name=Class A) EPR Object(Peer Address=R7_A Next Hop=R7_A) M3-R PCRpt Message CC-ID=X4(Symbolic Path Name=Class A) EPR Object(Peer Address=R7_A Next Hop=R7_A) Figure 2: Explicit Route Establish Procedures(From R1 to R7) Wang, et al. Expires April 23, 2021 [Page 10] Internet-Draft PCEP Extension for Native IP Network October 2020 -------------------------------------------------------------------------+ | | v +------------------+ | M1 PCInitiate Message: +----------+ PCE +-----+-----+ CC-ID=X7(Symbolic Path Name=Class A) | +----^---^---^-----+ | EPR Object(Peer Address=R1_A | | | | | Next Hop=R4_A) | | | | | | | | | | M1-R PCRpt Message: | | | | | CC-ID=X7 | | +v-+ | | EPR Object(Peer Address=R1_A +------------+ +---+R3+-------------------+ ) Next Hop=R4_A) | | +--+ | | | | | | +v-+ +--+ | | +--+ +-v+ |R1+------+R5++ +----------------+R6+----+R7| ++-+ +--+ | | +--+ +-++ | | | | M3 PCInitiate Message | +---+ +---+ | CC-ID=X2(Symbolic Path Name=Class A) | +v-+ | | +v-+ | EPR Object(Peer Address=R1_A +----------+R2+-+ +--------+R4+-----------+ Next Hop=R1_A) | | | | M3-R PCRpt Message | | CC-ID=X2(Symbolic Path Name=Class A) <----------------------+ | EPR Object(Peer Address=R1_A | Next Hop=R1_A) | v M2 PCInitiate Message CC-ID=X4(Symbolic Path Name=Class A) EPR Object(Peer Address=R1_A Next Hop=R2_A) M2-R PCRpt Message CC-ID=X4(Symbolic Path Name=Class A) EPR Object(Peer Address=R1_A Next Hop=R2_A) Figure 3: Explicit Route Establish Procedures(From R7 to R1) Upon the error occurs, the PCC SHOULD send the corresponding error(Error-type=TBD, Error-value=03) information that defined in Section 8. When the peer info that associated with the Symbolic Path Name is not the same as the peer info that indicated in EPR object in PCC, an error (Error-type=TBD, Error-value=04) should be reported via the PCRpt message. Wang, et al. Expires April 23, 2021 [Page 11] Internet-Draft PCEP Extension for Native IP Network October 2020 6.3. BGP Prefix Advertisement Procedures The detail procedures for BGP prefix advertisement is shown below, using PCInitiate and PCRpt message pair. The PCInitiate message should be sent to PCC that acts as BGP peer router only. In the example, it should be sent to R1(M1) and R7(M2) respectively. When PCC receives the PPA and the CCI object (with the R bit set to 0 in SRP object) in PCInitiate message, the PCC should send the prefixes indicated in this object to the appointed BGP peer. When PCC sends successfully the prefixes to the appointed BGP peer, it should report the result via the PCRpt messages, with PPA object included, and the corresponding SRP and CCI object. When PCC receives the PPA and the CCI object with the R bit set to 1 in SRP object in PCInitiate message, the PCC should withdraw the prefixes advertisement to the peer that indicated by this object. When PCC withdraws successfully the prefixes that indicated by this object, it should report the result via the PCRpt message, with the PPA object included, and the corresponding SRP and CCI object. The IPv4 prefix MUST only be advertised via the IPv4 BGP session and the IPv6 prefix MUST only be advertised via the IPv6 BGP session. If mismatch occur, an error(Error-type=TBD, Error-value=05) should be reported. When the peer info that associated with the Symbolic Path Name is not the same as the peer info that indicated in PPA object in PCC, an error (Error-type=TBD, Error-value=06) should be reported via the PCRpt message. Wang, et al. Expires April 23, 2021 [Page 12] Internet-Draft PCEP Extension for Native IP Network October 2020 M2 PCInitiate Message: CC-ID=X7(Symbolic Path Name=Class A) PPA Object(Peer IP=R1_A, Prefix=7_A) <-----+ M2-R PCRpt Message: | CC-ID=X7 | PPA Object(Peer IP=R1_A, Prefix=7_A) | | | | +------------------+ | M1 PCInitiate Message: +----------+ PCE +-----------+ | CC-ID=X1(Symbolic Path Name=Class A) | +------------------+ | | PPA Object(Peer IP=R7_A, Prefix=1_A) | | | | | | <----------+ +---+ M1-R PCRpt Message: | | CC-ID=X1 | +--+ | PPA Object(Peer IP=R7_A,Prefix=1_A) +------------------+R3+-------------------+ ) | +--+ | | | +v-+ +--+ +--+ +-v+ |R1+----------+R5+----------+R6+---------+R7| ++-+ +--+ +--+ +-++ | | | | | +--+ +--+ | +------------+R2+----------+R4+-----------+ Figure 4: BGP Prefix Advertisement Procedures 7. New PCEP Objects One new CCI Object and three new PCEP objects are defined in this draft. All new PCEP objects are as per [RFC5440] 7.1. CCI Object The Central Control Instructions (CCI) Object is used by the PCE to specify the forwarding instructions is defined in [I-D.ietf-pce-pcep-extension-for-pce-controller]. This document defines another object-type for Native-IP. CCI Object-Type is TBD for Native-IP as below Wang, et al. Expires April 23, 2021 [Page 13] Internet-Draft PCEP Extension for Native IP Network October 2020 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | CC-ID | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Reserved | Flags | +---------------------------------------------------------------+ | | // Optional TLV // | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 5: CCI Object for Native IP Figure 1 The field CC-ID is as described in [I-D.ietf-pce-pcep-extension-for-pce-controller]. Following fields are defined for CCI Object-Type TBD Reserved: is set to zero while sending, ignored on receipt. Flags: is used to carry any additional information pertaining to the CCI. Currently no flag bits are defined. The Symbolic Path Name TLV [RFC8231] MUST be included in the CCI Object-Type TBD to identify the end to end TE path in Native IP environment and MUST be unique. 7.2. BGP Peer Info Object The BGP Peer Info object is used to specify the information about the peer that the PCC should establish the BGP relationship with. This object should only be included and sent to the head and end router of the E2E path in case there is no Route Reflection (RR) involved. If the RR is used between the head and end routers, then such information should be sent to head router, RR and end router respectively. By default, there MUST be no prefix be distributed via such BGP session that established by this object. By default, the Local/Peer IP address SHOULD be dedicated to the usage of native IP TE solution, and SHOULD NOT be used by other BGP sessions that established by manual or non PCE initiated configuration. BGP Peer Info Object-Class is TBD Wang, et al. Expires April 23, 2021 [Page 14] Internet-Draft PCEP Extension for Native IP Network October 2020 BGP Peer Info Object-Type is 1 for IPv4 and 2 for IPv6 The format of the BGP Peer Info object body for IPv4(Object-Type=1) is as follows: 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Peer AS Number | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ETTL | Reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Local IP Address | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Peer IP Address | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Additional TLVs | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 6: BGP Peer Info Object Body Format for IPv4 The format of the BGP Peer Info object body for IPv6(Object-Type=2) is as follows: Wang, et al. Expires April 23, 2021 [Page 15] Internet-Draft PCEP Extension for Native IP Network October 2020 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Peer AS Number | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ETTL | Reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | + + | Local IP Address (16 bytes) | + + | | + + | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | + + | Peer IP Address (16 bytes) | + + | | + + | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Additional TLVs | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 7: BGP Peer Info Object Body Format for IPv6 Peer AS Number: 4 Bytes, to indicate the AS number of Remote Peer. ETTL: 1 Bytes, to indicate the multi hop count for EBGP session. It should be 0 and ignored when Local AS and Peer AS is same. Reserved: is set to zero while sending, ignored on receipt.. Local IP Address(4/16 Bytes): IP address of the local router, used to peer with other end router. When Object-Type is 1, length is 4 bytes; when Object-Type is 2, length is 16 bytes. Peer IP Address(4/16 Bytes): IP address of the peer router, used to peer with the local router. When Object-Type is 1, length is 4 bytes; when Object-Type is 2, length is 16 bytes; Additional TLVs: TLVs that associated with this object, can be used to convey other necessary information for dynamic BGP session establishment. Its definition is out of the current document. Wang, et al. Expires April 23, 2021 [Page 16] Internet-Draft PCEP Extension for Native IP Network October 2020 7.3. Explicit Peer Route Object The Explicit Peer Route object is defined to specify the explicit peer route to the corresponding peer address on each device that is on the E2E assurance path. This Object should be sent to all the devices that locates on the E2E assurance path that calculated by PCE. The path established by this object should have higher priority than other path calculated by dynamic IGP protocol, but should be lower priority that the static route configured by manual or NETCONF channel. Explicit Peer Route Object-Class is TBD. Explicit Peer Route Object-Type is 1 for IPv4 and 2 for IPv6 The format of Explicit Peer Route object body for IPv4(Object-Type=1) is as follows: 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Route Priority | Reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | IPv4 Peer Address | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Next Hop Address to the IPv4 Peer Address | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 8: Explicit Peer Route Object Body Format for IPv4 The format of Explicit Peer Route object body for IPv6(Object-Type=2) is as follows: Wang, et al. Expires April 23, 2021 [Page 17] Internet-Draft PCEP Extension for Native IP Network October 2020 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Route Priority | Reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | + + | IPv6 Peer Address | + + | | + + | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | + + | Next Hop Address to the IPv6 Peer Address | + + | | + + | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 9: Explicit Peer Route Object Body Format for IPv6 Route Priority: 2 Bytes, The priority of this explicit route. The higher priority should be preferred by the device. Reserved.: is set to zero while sending, ignored on receipt. Peer Address: To indicate the peer address. Next Hop Address to the Peer: To indicate the next hop address to the corresponding peer. 7.4. Peer Prefix Association Object The Peer Prefix Association object is defined to specify the IP prefixes that should be advertised to the corresponding peer. This object should only be included and sent to the head/end router of the end2end path. The prefixes information included in this object MUST only be advertised to the indicated peer, MUST NOT be advertised to other BGP peers. Peer Prefix Association Object-Class is TBD Peer Prefix Association Object-Type is 1 for IPv4 and 2 for IPv6 Wang, et al. Expires April 23, 2021 [Page 18] Internet-Draft PCEP Extension for Native IP Network October 2020 The format of the Peer Prefix Association object body is as follows: 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Peer IPv4 Address | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | // IPv4 Prefix subobjects // | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 10: Peer Prefix Association Object Body Format for IPv4 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Peer IPv6 Address | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | // IPv6 Prefix subobjects // | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 11: Peer Prefix Association Object Body Format for IPv6 Peer IPv4 Address: 4 Bytes. Identifies the peer IPv4 address that the associated prefixes will be sent to. IPv4 Prefix subojects: List of IPv4 Prefix subobjects that defined in [RFC3209], identify the prefixes that will be sent to the peer that identified by Peer IPv4 Address List. Peer IPv6 Address: 16 Bytes. Identifies the peer IPv6 address that the associated prefixes will be sent to. IPv6 Prefix subojects: List of IPv6 Prefix subobjects that defined in [RFC3209], identify the prefixes that will be sent to the peer that identified by Peer IPv6 Address List. 8. New Error-Types and Error-Values Defined A PCEP-ERROR object is used to report a PCEP error and is characterized by an Error-Type that specifies that type of error and an Error-value that provides additional information about the error. An additional Error-Type and several Error-values are defined to represent some the errors related to the newly defined objects, which are related to Native IP TE procedures. Wang, et al. Expires April 23, 2021 [Page 19] Internet-Draft PCEP Extension for Native IP Network October 2020 +============+===============+==============================+ | Error-Type | Meaning | Error-value | +============+===============+==============================+ | TBD | Native IP | | | | TE failure | | +------------+---------------+------------------------------+ | | | 0: Unassigned | +------------+---------------+------------------------------+ | | | 1: Peer AS not match | +------------+---------------+------------------------------+ | | | 2: Peer IP can't be reached | +------------+---------------+------------------------------+ | | | 3: Explicit Peer Route Error | +------------+---------------+------------------------------+ | | | 4: EPR/BPI Peer Info mismatch| +------------+---------------+------------------------------+ | | | 5: BPI/PPA Object AF mismatch| +------------+---------------+------------------------------+ | | | 6: PPA/BPI Peer Info mismatch| +------------+---------------+------------------------------+ | | | 7: | +------------+---------------+------------------------------+ | | | 8: | +------------+---------------+------------------------------+ | | | 8: | +------------+---------------+------------------------------+ | | | 9: | +------------+---------------+------------------------------+ Figure 12: Newly defined Error-Type and Error-Value 9. Management Consideration The information transferred in this draft is mainly used for the light weight BGP session setup, explicit route deployment and the prefix distribution. The planning, allocation and distribution of the peer addresses within IGP should be accomplished in advanced and they are out of the scope of this draft. [RFC8232] describes the state synchronization procedure between stateful PCE and PCC. The communication of PCE and PCC described in this draft should also follow this procedures, treat the three newly defined objects that associated with the same symbolic path name as the attribute of the same path in the LSP-DB. When PCE detects one or some of the PCCs are out of control, it should recompute and redeploy the traffic engineering path for native IP on the active PCCs. When PCC detects that it is out of control of the PCE, it should clear the information that initiated by the PCE. Wang, et al. Expires April 23, 2021 [Page 20] Internet-Draft PCEP Extension for Native IP Network October 2020 The PCE should assures the avoidance of possible transient loop in such node failure when it deploy the explicit peer route on the PCCs. 10. Security Considerations Service provider should consider the protection of PCE and their communication with the underlay devices, which is described in document [RFC5440] and [RFC8253] 11. IANA Considerations 11.1. PCEP Object Types IANA is requested to allocate new registry for the PCEP Object Type: Object-Class Value Name Reference TBD CCI Object This document Object-Type TBD: Native IP TBD BGP Peer Info This document Object-Type 1: IPv4 address 2: IPv6 address TBD Explicit Peer Route This document Object-Type 1: IPv4 address 2: IPv6 address TBD Peer Prefix Association This document Object-Type 1: IPv4 address 2: IPv6 address 12. Contributor Dhruv Dhody has contributed the contents of this draft. 13. Acknowledgement Thanks Mike Koldychev, Siva Sivabalan, Adam Simpson for his valuable suggestions and comments. Wang, et al. Expires April 23, 2021 [Page 21] Internet-Draft PCEP Extension for Native IP Network October 2020 14. Normative References [I-D.ietf-pce-pcep-extension-for-pce-controller] Li, Z., Peng, S., Negi, M., Zhao, Q., and C. Zhou, "PCEP Procedures and Protocol Extensions for Using PCE as a Central Controller (PCECC) of LSPs", draft-ietf-pce-pcep- extension-for-pce-controller-07 (work in progress), September 2020. [I-D.ietf-teas-pce-native-ip] Wang, A., Khasanov, B., Zhao, Q., and H. Chen, "PCE in Native IP Network", draft-ietf-teas-pce-native-ip-11 (work in progress), August 2020. [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, . [RFC3209] Awduche, D., Berger, L., Gan, D., Li, T., Srinivasan, V., and G. Swallow, "RSVP-TE: Extensions to RSVP for LSP Tunnels", RFC 3209, DOI 10.17487/RFC3209, December 2001, . [RFC5440] Vasseur, JP., Ed. and JL. Le Roux, Ed., "Path Computation Element (PCE) Communication Protocol (PCEP)", RFC 5440, DOI 10.17487/RFC5440, March 2009, . [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, May 2017, . [RFC8231] Crabbe, E., Minei, I., Medved, J., and R. Varga, "Path Computation Element Communication Protocol (PCEP) Extensions for Stateful PCE", RFC 8231, DOI 10.17487/RFC8231, September 2017, . [RFC8232] Crabbe, E., Minei, I., Medved, J., Varga, R., Zhang, X., and D. Dhody, "Optimizations of Label Switched Path State Synchronization Procedures for a Stateful PCE", RFC 8232, DOI 10.17487/RFC8232, September 2017, . Wang, et al. Expires April 23, 2021 [Page 22] Internet-Draft PCEP Extension for Native IP Network October 2020 [RFC8253] Lopez, D., Gonzalez de Dios, O., Wu, Q., and D. Dhody, "PCEPS: Usage of TLS to Provide a Secure Transport for the Path Computation Element Communication Protocol (PCEP)", RFC 8253, DOI 10.17487/RFC8253, October 2017, . [RFC8281] Crabbe, E., Minei, I., Sivabalan, S., and R. Varga, "Path Computation Element Communication Protocol (PCEP) Extensions for PCE-Initiated LSP Setup in a Stateful PCE Model", RFC 8281, DOI 10.17487/RFC8281, December 2017, . [RFC8283] Farrel, A., Ed., Zhao, Q., Ed., Li, Z., and C. Zhou, "An Architecture for Use of PCE and the PCE Communication Protocol (PCEP) in a Network with Central Control", RFC 8283, DOI 10.17487/RFC8283, December 2017, . [RFC8408] Sivabalan, S., Tantsura, J., Minei, I., Varga, R., and J. Hardwick, "Conveying Path Setup Type in PCE Communication Protocol (PCEP) Messages", RFC 8408, DOI 10.17487/RFC8408, July 2018, . [RFC8735] Wang, A., Huang, X., Kou, C., Li, Z., and P. Mi, "Scenarios and Simulation Results of PCE in a Native IP Network", RFC 8735, DOI 10.17487/RFC8735, February 2020, . Authors' Addresses Aijun Wang China Telecom Beiqijia Town, Changping District Beijing, Beijing 102209 China Email: wangaj3@chinatelecom.cn Boris Khasanov Huawei Technologies,Co.,Ltd Moskovskiy Prospekt 97A St.Petersburg 196084 Russia Email: bhassanov@yahoo.com Wang, et al. Expires April 23, 2021 [Page 23] Internet-Draft PCEP Extension for Native IP Network October 2020 Sheng Fang Huawei Technologies,Co.,Ltd Huawei Bld., No.156 Beiqing Rd. Beijing China Email: fsheng@huawei.com Ren Tan Huawei Technologies,Co.,Ltd Huawei Bld., No.156 Beiqing Rd. Beijing China Email: tanren@huawei.com Chun Zhu ZTE Corporation 50 Software Avenue, Yuhua District Nanjing, Jiangsu 210012 China Email: zhu.chun1@zte.com.cn Wang, et al. Expires April 23, 2021 [Page 24]