Softwire Working Group Q. Sun Internet-Draft H. Wang Intended status: Standards Track Y. Cui Expires: October 9, 2015 Tsinghua University I. Farrer Deutsche Telekom AG M. Boucadair France Telecom R. Asati Cisco Systems, Inc. April 7, 2015 YANG Data Model for IPv4-in-IPv6 Softwire draft-sun-softwire-yang-03 Abstract This document defines a YANG data model for the configuration and management of IPv4-in-IPv6 Softwire Border Routers and Customer Premises Equipment. It covers Lightweight 4over6, MAP-E and MAP-T Softwire mechanisms. Requirements Language The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in [RFC2119]. 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 http://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." This Internet-Draft will expire on October 9, 2015. Sun, et al. Expires October 9, 2015 [Page 1] Internet-Draft YANG for softwire April 2015 Copyright Notice Copyright (c) 2015 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 (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3 1.2. YANG Tree Diagrams . . . . . . . . . . . . . . . . . . . 4 1.3. YANG Modelling of NAT44 Functionality . . . . . . . . . . 4 2. Objectives . . . . . . . . . . . . . . . . . . . . . . . . . 4 2.1. Common . . . . . . . . . . . . . . . . . . . . . . . . . 4 2.2. Lightweight 4over6 . . . . . . . . . . . . . . . . . . . 5 2.3. MAP-E . . . . . . . . . . . . . . . . . . . . . . . . . . 5 2.4. MAP-T . . . . . . . . . . . . . . . . . . . . . . . . . . 5 3. Softwire YANG Tree Diagrams . . . . . . . . . . . . . . . . . 5 3.1. Common Tree Diagrams . . . . . . . . . . . . . . . . . . 5 3.2. Lightweight 4over6 Tree Diagrams . . . . . . . . . . . . 6 3.3. MAP-E Tree Diagrams . . . . . . . . . . . . . . . . . . . 9 3.4. MAP-T Tree Diagrams . . . . . . . . . . . . . . . . . . . 10 3.5. Notifications for Softwire YANG . . . . . . . . . . . . . 12 4. Softwire YANG Model . . . . . . . . . . . . . . . . . . . . . 14 5. Example of Configure Lw4over6 Binding-Table . . . . . . . . . 30 6. Security Considerations . . . . . . . . . . . . . . . . . . . 31 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 32 8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 32 9. References . . . . . . . . . . . . . . . . . . . . . . . . . 32 9.1. Normative References . . . . . . . . . . . . . . . . . . 32 9.2. Informative References . . . . . . . . . . . . . . . . . 33 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 33 1. Introduction The IETF Softwire Working Group has developed several IPv4-in-IPv6 Softwire mechanisms to address various deployment contexts and constraints. As a companion to the architectural specification documents, this document focuses on the provisioning aspects for Sun, et al. Expires October 9, 2015 [Page 2] Internet-Draft YANG for softwire April 2015 softwire functional elements that are: Border Routers (BRs) and Customer Premises Equipment (CEs). This document defines a YANG data model that can be used to configure and manage IPv4-in-IPv6 Softwire BRs and/or CEs via NETCONF protocol[RFC6241]. To ensure interoperability in mixed vendor environments, it is important that the models can be easily reused between different vendors and implementations. There are three different mechanisms in this YANG model. Each specific mechanism has their separate YANG modules respectively: o Lightweight 4over6 [I-D.ietf-softwire-lw4over6] o MAP-E [I-D.ietf-softwire-map] o MAP-T [I-D.ietf-softwire-map-t] This model is structured into two root containers: 1. Container "softwire-config" holds the collection of YANG definitions common to all softwire configuration of BRs and CEs. 2. Container "softwire-state" holds YANG definitions for the operational state of the Softwire BRs and CEs. The model also includes a notification module. The aim is to notify the client that a specific status has been changed. This approach has been taken so that the model can be easily extended in the future to support additional softwire mechanism, should this be necessary. 1.1. Terminology The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in [RFC2119]. The reader should be familiar with the terms defined in [I-D.ietf-softwire-lw4over6] [I-D.ietf-softwire-map] [I-D.ietf-softwire-map-t] , and the YANG data modelling language [RFC6020]. Sun, et al. Expires October 9, 2015 [Page 3] Internet-Draft YANG for softwire April 2015 1.2. YANG Tree Diagrams Softwire YANG tree diagrams provide a concise representation of a YANG module to help readers understand the module structure. The meaning if the symbols in these diagrams is as follows: o Brackets "[" and "]" enclose list keys. o Braces "{" and "}" enclose feature content. o Parentheses "(" and ")" enclose choice and case nodes, and case nodes are also marked with a colon (":"). o Symbols after data node names: "?" means an optional node, and "*" denotes a list and leaf-list. o Abbreviations before data node names: "rw" means configuration data (read-write), and "ro" means state data (read-only). 1.3. YANG Modelling of NAT44 Functionality This documented model does not include NAT-specific provisioning parameters other than the external IP address and port set which a softwire client may use for NAT44. Additional NAT-specific considerations are out of scope. 2. Objectives This document defines a YANG data model that can be used to configure and manage BRs and CEs for the following IPv4-in-IPv6 Softwire mechanisms: Lightweight 4over6, MAP-E and MAP-T. For the Lightweight 4over6, the configuration and management information of lwB4 and lwAFTR are different. The Lightweight 4over6 AFTRs needs to maintain the binding table of lwB4s. The Lightweight 4over6 B4s need to maintain the NAPT table of hosts. For the MAP-T and MAP-T, CE and BR both need to maintain the map-rule table. Thus, there is no need to distinguish BR and CE. 2.1. Common This common model abstracts the shared features of different BRs and CEs. The model defined a single node softwire description for common feature now. The following sections of the document are structured with the root of the softwire YANG model (common to all mechanisms) described Sun, et al. Expires October 9, 2015 [Page 4] Internet-Draft YANG for softwire April 2015 first. The subsequent sections describe the models relevant to the different softwire mechanisms. All functions are listed, but the YANG models use the "feature" statement to distinguish among the different softwire mechanisms. 2.2. Lightweight 4over6 Lightweight 4over6 include two elements: lwAFTR and lwB4. The lwAFTR holds configuration for IPv4-IPv6 address bindings which used for the forwarding of traffic originating from lwB4s. And the lwB4 is configured with the relevant parameters for establishing the IPv4 in IPv6 tunnel including an IPv6 address for the lwAFTR and the IPv4 configuration for NAPT44. 2.3. MAP-E MAP-E elements (BR and CE) are provisioned with the MAP rules necessary for defining MAP domains and forwarding rules. 2.4. MAP-T MAP-E elements (BR and CE) are provisioned with the MAP rules necessary for defining MAP domains and forwarding rules. MAP-T CEs an additional "ipv6-prefix" parameter is also configured. 3. Softwire YANG Tree Diagrams 3.1. Common Tree Diagrams Figure 1 describes the softwire data model which is common to all of the different softwire mechanisms listed in Section 1: Sun, et al. Expires October 9, 2015 [Page 5] Internet-Draft YANG for softwire April 2015 +--rw softwire-config | +--rw description? string | +--rw lw4over6 {lw4over6}? | | +--rw lwaftr {lwaftr}? | | +--rw lwb4 {lwb4}? | +--rw map-e {map-e}? | +--rw map-t {map-t}? | +--ro softwire-state +--ro description? string +--ro lw4over6 {lw4over6}? | +--ro lwaftr {lwaftr}? | +--ro lwb4 {lwb4}? +--ro map-e {map-e}? +--ro map-t {map-t}? Figure 1: Softwire Common Data Model Structure The mechanism specific models for lw4over6, MAP-E and MAP-T are described in detail in the following sections. 3.2. Lightweight 4over6 Tree Diagrams Figure 2 defines the softwire data model for Lightweight 4over6 which include lwAFR and lwB4: +--rw softwire-config | +--... | +--rw lw4over6 {lw4over6}? | | +--rw lwaftr {lwaftr}? | | | +--rw enable? boolean | | | +--rw lwaftr-instances | | | +--rw lwaftr-instance* [id] | | | +--rw id uint32 | | | +--rw name? string | | | +--rw binding-table | | | | +--rw binding-entry* [binding-ipv6-addr] | | | | +--rw binding-ipv6-addr inet:ipv6-address | | | | +--rw binding-ipv4-addr inet:ipv4-address | | | | +--rw port-set | | | | | +--rw offset uint8 | | | | | +--rw psid uint16 | | | | | +--rw psid-len uint8 | | | | +--rw lwaftr-ipv6-addr? inet:ipv6-prefix | | | | +--rw lifetime? uint32 | | | +--rw tunnels | | | | +--rw tunnel* [tunnel-id] | | | | +--rw tunnel-id uint8 Sun, et al. Expires October 9, 2015 [Page 6] Internet-Draft YANG for softwire April 2015 | | | | +--rw tunnel-mtu uint32 | | | | +--rw fragment-mru uint16 | | | +--rw tunnel-num-threshold uint32 | | +--rw lwb4 {lwb4}? | | +--rw enable? boolean | | +--rw lwb4-instances | | +--rw lwb4-instance* [binding-ipv6info] | | +--rw name? string | | +--rw b4-ipv6-addr-format boolean | | +--rw binding-ipv6info union | | +--rw binding-ipv4-addr inet:ipv4-address | | +--rw port-set | | | +--rw offset uint8 | | | +--rw psid uint16 | | | +--rw psid-len uint8 | | +--rw lwaftr-ipv6-addr? inet:ipv6-prefix | | +--rw tunnels | | +--rw tunnel* [tunnel-id] | | +--rw tunnel-id uint8 | | +--rw tunnel-mtu uint32 | | +--rw fragment-mru uint16 | +--... +--ro softwire-state +--... +--ro lw4over6 {lw4over6}? | +--ro lwaftr {lwaftr}? | | +--ro lwaftr-instances | | +--ro lwaftr-instance* [id] | | +--ro id uint32 | | +--ro name? string | | +--ro active-tunnel-num? uint32 | | +--ro binding-table | | | +--ro binding-entry* [binding-ipv6-addr] | | | +--ro binding-ipv6-addr inet:ipv6-address | | | +--ro active? boolean | | +--ro traffic-stat | | +--ro sentPacket? yang:zero-based-counter64 | | +--ro sentByte? yang:zero-based-counter64 | | +--ro rcvdPacket? yang:zero-based-counter64 | | +--ro rcvdByte? yang:zero-based-counter64 | | +--ro droppedPacket? yang:zero-based-counter64 | | +--ro droppedByte? yang:zero-based-counter64 | +--ro lwb4 {lwb4}? | +--ro lwb4-instances | +--ro lwb4-instance* [binding-ipv6info] | +--ro name? string | +--ro binding-ipv6info union | +--ro traffic-stat Sun, et al. Expires October 9, 2015 [Page 7] Internet-Draft YANG for softwire April 2015 | +--ro sentPacket? yang:zero-based-counter64 | +--ro sentByte? yang:zero-based-counter64 | +--ro rcvdPacket? yang:zero-based-counter64 | +--ro rcvdByte? yang:zero-based-counter64 | +--ro droppedPacket? yang:zero-based-counter64 | +--ro droppedByte? yang:zero-based-counter64 +--... Figure 2: Softwire Lightweight 4over6 Data Model Structure Introduction of important lwAFTR nodes: o binding-entry: used to define the binding relationship between 3-tuples, which contains the lwB4's IPv6 address, the allocated IPv4 address and restricted port-set. For detail information, please refer to [I-D.ietf-softwire-lw4over6]. o tunnel-mtu: used to set the value of MTU for Lightweight 4over6 tunnel. o fragment-mru: used to the value of fragment for Lightweight 4over6 tunnel. o tunnel-num-threshold: used to set the maximum number of tunnels that can be created on the lw4over6 device simultaneously. o active-tunnel-num (ro): used to present the number of tunnels currently provisioned on the device. o active (ro): used to show the status of particular binding-entry. o stat-count (ro): use to show the numbers of packets and bytes information of specific device respectively. Introduction of important lwB4 nodes: o b4-ipv6-addr-format: indicates the format of lwB4 IPv6 address. If set to true, it indicates that the IPv6 source address of the lwB4 is constructed according to the description in [I-D.ietf-softwire-lw4over6]; if set to false, the lwB4 can use any /128 address from the assigned IPv6 prefix. o binding-ipv6info: used to set the IPv6 address type which is combined in a binding entry, for a complete address or a prefix. o stat-count (ro): use to show the numbers of packets and bytes information of specific device respectively. Sun, et al. Expires October 9, 2015 [Page 8] Internet-Draft YANG for softwire April 2015 3.3. MAP-E Tree Diagrams Figure 3 defines the softwire data model for MAP-E: module: ietf-softwire +--rw softwire-config | +--... | +--rw map-e {map-e}? | | +--rw enable? boolean | | +--rw map-e-instances | | +--rw map-e-instance* [id] | | +--rw id uint32 | | +--rw name? string | | +--rw map-rules | | | +--rw map-rule* [id] | | | +--rw id uint8 | | | +--rw map-rule-type enumeration | | | +--rw rule-ipv6-prefix inet:ipv6-prefix | | | +--rw rule-ipv4-prefix inet:ipv4-prefix | | | +--rw port-set | | | | +--rw offset uint8 | | | | +--rw psid uint16 | | | | +--rw psid-len uint8 | | | +--rw ea-len uint8 | | +--rw br-ipv6-addr? inet:ipv6-address | | +--rw tunnels | | +--rw tunnel* [tunnel-id] | | +--rw tunnel-id uint8 | | +--rw tunnel-mtu uint32 | | +--rw fragment-mru uint16 | +--... +--ro softwire-state +--... +--ro map-e {map-e}? | +--ro map-e-instances | +--ro map-e-instance* [id] | +--ro id uint32 | +--ro name? string | +--ro traffic-stat | +--ro sentPacket? yang:zero-based-counter64 | +--ro sentByte? yang:zero-based-counter64 | +--ro rcvdPacket? yang:zero-based-counter64 | +--ro rcvdByte? yang:zero-based-counter64 | +--ro droppedPacket? yang:zero-based-counter64 | +--ro droppedByte? yang:zero-based-counter64 +--... Figure 3: Softwire MAP-E Data Model Structure Sun, et al. Expires October 9, 2015 [Page 9] Internet-Draft YANG for softwire April 2015 Introduction of important MAP-E nodes: o map-rule-type: used to define the type of map rule. The data type is enumeration, which are "BMR" and "FMR". o offset: used to set the number of offset bits. o psid: used to algorithmically identify a set of ports exclusively for a specific softwire. o ea-len: used to set the length of the Embedded-Address (EA), which defined in the mapping rule for a MAP domain. o tunnel-mtu: used to set the value of MTU for MAP-E tunnel. o fragment-mru: used to the value of fragment for MAP-E tunnel. o stat-count (ro): use to show the numbers of packets and bytes information of specific device respectively. 3.4. MAP-T Tree Diagrams Figure 4 defines the softwire data model for MAP-T: Sun, et al. Expires October 9, 2015 [Page 10] Internet-Draft YANG for softwire April 2015 module: ietf-softwire +--rw softwire-config | +--... | +--rw map-t {map-t}? | +--rw enable? boolean | +--rw map-t-instances | +--rw map-t-instance* [id] | +--rw id uint32 | +--rw name? string | +--rw map-rules | | +--rw map-rule* [id] | | +--rw id uint8 | | +--rw map-rule-type enumeration | | +--rw rule-ipv6-prefix inet:ipv6-prefix | | +--rw rule-ipv4-prefix inet:ipv4-prefix | | +--rw port-set | | | +--rw offset uint8 | | | +--rw psid uint16 | | | +--rw psid-len uint8 | | +--rw ea-len uint8 | +--rw dmr-ipv6-prefix? inet:ipv6-prefix +--ro softwire-state +--... +--ro map-t {map-t}? +--ro map-t-instances +--ro map-t-instance* [id] +--ro id uint32 +--ro name? string +--ro traffic-stat +--ro sentPacket? yang:zero-based-counter64 +--ro sentByte? yang:zero-based-counter64 +--ro rcvdPacket? yang:zero-based-counter64 +--ro rcvdByte? yang:zero-based-counter64 +--ro droppedPacket? yang:zero-based-counter64 +--ro droppedByte? yang:zero-based-counter64 Figure 4: Softwire MAP-T Data Model Structure Introduction of important MAP-T nodes: o map-rule-type: is used to define the type of map rule. The data type is enumeration, which are "BMR" and "FMR". o offset: is used to set the number of offset bits. o psid: is used to algorithmically identify a set of ports exclusively for a specific softwire. Sun, et al. Expires October 9, 2015 [Page 11] Internet-Draft YANG for softwire April 2015 o ea-len: is used to set the length of the Embedded-Address (EA), which defined in the mapping rule for a MAP domain. o dmr-ipv6-prefix: defines the DMR in MAP-T. o stat-count (ro): use to show the numbers of packets and bytes information of specific device respectively. 3.5. Notifications for Softwire YANG This section describes the diagram tree for the notifications. These notifications pertain to configuration and monitoring portions of specific Softwire mechanisms. The logic is that, the softwire instance notifies the NETCONF client with the index for a mapping entry and then the NETCONF client retrieves the related information from the operational datastore of that instance. Sun, et al. Expires October 9, 2015 [Page 12] Internet-Draft YANG for softwire April 2015 module: ietf-softwire notifications: +---n softwire-lwaftr-event {lwaftr}? | +--ro lwaftr-id -> /softwire-state/lwaftr/lwaftr-instances/ | | lwaftr-instance/id | +--ro invalid-entry* -> /softwire-config/lwaftr/lwaftr-instances/ | | lwaftr-instance[id=current()/../lwaftr-id]/ | | binding-table/binding-entry/binding-ipv6-addr | +--ro added-entry* inet:ipv6-address | +--ro modified-entry* -> /softwire-config/lwaftr/lwaftr-instances/ | lwaftr-instance[id=current()/../lwaftr-id]/ | binding-table/binding-entry/binding-ipv6-addr +---n softwire-lwb4-event {lwb4}? | +--ro lwb4-binding-ipv6-addr-change inet:ipv6-address +---n softwire-map-e-event {map-e}? | +--ro map-e-id -> /softwire-config/map-e/map-e-instances/ | | map-e-instance/id | +--ro invalid-entry-id* -> /softwire-config/map-e/map-e-instances/ | | map-e-instance[id=current()/../map-e-id]/ | | map-rules/map-rule/id | +--ro added-entry* uint32 | +--ro modified-entry* -> /softwire-config/map-e/map-e-instances/ | | map-e-instance[id=current()/../map-e-id]/ | | map-rules/map-rule/id +---n softwire-map-t-event {map-t}? +--ro map-t-id -> /softwire-config/map-t/map-t-instances/ | map-t-instance/id +--ro invalid-entry-id* -> /softwire-config/map-t/map-t-instances/ | map-t-instance[id=current()/../map-t-id]/ | map-rules/map-rule/id +--ro added-entry* uint32 +--ro modified-entry* -> /softwire-config/map-t/map-t-instances/ map-t-instance[id=current()/../map-t-id]/ map-rules/map-rule/id Figure 5: Softwire Notifications Data Model Structure Introduction of important notification nodes: o invalid-entry, added-entry, modified-entry: use to notify the client that a specific binding entry has been expired/invalid, added, or modified respectively. Same meaning for map rule list. o lwb4-binding-ipv6-addr-change: use to present the lwB4's binding- ipv6-address has been changed or the value of the 'b4-ipv6-addr- format' is "false". Sun, et al. Expires October 9, 2015 [Page 13] Internet-Draft YANG for softwire April 2015 4. Softwire YANG Model This module imports typedefs from [RFC6991]. file "ietf-softwire@2015-04-07.yang" module ietf-softwire { namespace "urn:ietf:params:xml:ns:yang:softwire"; prefix "softwire"; import ietf-inet-types {prefix inet; } import ietf-yang-types {prefix yang; } organization "Softwire Working Group"; contact " Qi Sun sunqi@csnet1.cs.tsinghua.edu.cn Hao Wang wangh13@mails.tsinghua.edu.cn Yong Cui yong@csnet1.cs.tsinghua.edu.cn Ian Farrer ian.farrer@telekom.de Mohamed Boucadair mohamed.boucadair@orange.com Rajiv Asati rajiva@cisco.com "; description "This document defines a YANG data model for the configuration and management of IPv4-in-IPv6 Softwire Border Routers and Customer Premises Equipment. It covers Lightweight 4over6, MAP-E and MAP-T Softwire mechanisms. Copyright (c) 2014 IETF Trust and the persons identified as authors of the code. All rights reserved. This version of this YANG module is part of RFC XXX; see the RFC itself for full legal notices."; revision 2015-04-07 { description "Version-03: Integrate lw4over6; Updata state nodes; Correct grammar errors; Reuse groupings; Update descriptions. Simplify the model."; } revision 2015-02-10 { description "Version-02: Add notifications."; } Sun, et al. Expires October 9, 2015 [Page 14] Internet-Draft YANG for softwire April 2015 revision 2015-02-06 { description "Version-01: Correct grammar errors; Reuse groupings; Update descriptions."; } revision 2015-02-02 { description "Initial revision."; } /* * Features */ feature lw4over6 { description "Lightweight 4over6 (lw4over6) is an IPv4-over-IPv6 tunnelling transition mechanism. Lightweight 4over6 is a solution designed specifically for complete independence between IPv6 subnet prefix (and /128 IPv6 address) and IPv4 address with or without IPv4 address sharing. This is accomplished by maintaining state for each softwire (per-subscriber state) in the central lwAFTR and a hub-and-spoke forwarding architecture. In order to delegate the NAPT function and achieve IPv4 address sharing, port-restricted IPv4 addresses needs to be allocated to CEs."; reference "I-D.ietf-softwire-lw4over6"; } feature lwaftr { if-feature lw4over6; description "The AFTRs (BRs) for Lightweight 4over6, so-called lwAFTR. This feature indicates that a instance functions as a lwAFTR. A lwAFTR is an IPv4-in-IPv6 tunnel concentrator that maintains per-subscriber IPv4-IPv6 address binding."; } feature lwb4 { if-feature lw4over6; description "The B4s (CEs) for Lightweight 4over6, so-called lwB4. This feature indicates that a instance functions as a lwB4. A lwB4 is an IPv4-in-IPv6 tunnel initiator. It is dual-stack capable node, either a directly connected end-host or a CE. It sources IPv4 conncections using the configured port-set and the public IPv4 address."; Sun, et al. Expires October 9, 2015 [Page 15] Internet-Draft YANG for softwire April 2015 } feature map-e { description "MAP-E is an IPv6 transition mechanism for transporting IPv4 packets across an IPv6 network using IP encapsulation. MAP-E allows for a reduction of the amount of centralized state using rules to express IPv4/IPv6 address mappings. This introduces an algorithmic relationship between the IPv6 subnet and IPv4 address. This relationship also allows the option of direct, meshed connectivity between users. Alternatively, MAP-E can be configured to support IPv4/IPv6 indepent binding. This feature indicates the instance functions as a MAP-E instance."; reference "I-D.ietf-softwire-map"; } feature map-t { description "The Mapping of Address and Port - Translation (MAP-T) architecture is a double stateless NAT64 based solution. It uses the stateless algorithmic address & transport layer port mapping scheme defined in MAP-E. The MAP-T solution differs from MAP-E in the use of IPv4-IPv6 translation, rather than encapsulation, as the form of IPv6 domain transport. This feature indicates the instance functions as a MAP-T instance. "; reference "I-D.ietf-softwire-map-t"; } /* * Grouping */ grouping port-set { description "Use the PSID algorithm to represent a range of transport layer ports."; leaf offset { mandatory true; type uint8 { range 0..16; } description "The number of offset bits. In Lightweight 4over6, the defaul value is 0 for assigning one contiguous port range. In MAP-E/T, the default value is 6, which excludes system ports by default and assigns distributed port ranges. If the this parameter is Sun, et al. Expires October 9, 2015 [Page 16] Internet-Draft YANG for softwire April 2015 larger than 0, the value of offset MUST be greater than 0."; } leaf psid { mandatory true; type uint16; description "Port Set Identifier (PSID) value, which identifies a set of ports algorithmically."; } leaf psid-len { mandatory true; type uint8 { range 0..16; } description "The length of PSID, representing the sharing ratio for a IPv4 address."; } } grouping binding-entry { description "The lwAFTR maintains an address binding table that contains the binding between the lwB4's IPv6 address, the allocated IPv4 address and restricted port-set."; /* choice binding-ipv6info { description "Allow for the binding table to be specified in one of two ways, either with an explicit /128 or a /64 with the IID automatically constructed from the IPv4 address and port set."; case ipv6addr { leaf binding-ipv6-addr { mandatory true; type inet:ipv6-address; description "The /128 IPv6 address of the lwB4, which is used to bind the address and port-set and source the tunnel."; } } case ipv6pref { leaf binding-ipv6-prefix { mandatory true; type inet:ipv6-prefix; description "The operator-assigned IPv6 prefix of the lwB4. The lwAFTR uses the prefix to construct the /128 IPv6 address to complete the binding entry. "; Sun, et al. Expires October 9, 2015 [Page 17] Internet-Draft YANG for softwire April 2015 reference "http://tools.ietf.org/html/draft-ietf-softwire-lw4over6-13#section-5.1, Figure 3"; } } } */ leaf binding-ipv6info { mandatory true; type union { type inet:ipv6-address; type inet:ipv6-prefix; } description "The IPv6 information for a binding entry. If it's an IPv6 prefix, it indicates that the IPv6 source address of the lwB4 is constructed according to the description in [I-D.ietf-softwire-lw4over6]; if it's an IPv6 address, it means the lwB4 uses any /128 address from the assigned IPv6 prefix. "; } leaf binding-ipv4-addr { mandatory true; type inet:ipv4-address; description "The IPv4 address assigned to the lwB4, which is used as the IPv4 External Address for lwB4 local NAPT44."; } container port-set { uses port-set { refine offset { default "0"; } } } leaf lwaftr-ipv6-addr { type inet:ipv6-prefix; description "The IPv6 address for lwaftr. Optional for the binding entry."; } leaf lifetime { type uint32; units seconds; } } /* grouping nat-table { Sun, et al. Expires October 9, 2015 [Page 18] Internet-Draft YANG for softwire April 2015 description "Grouping 'nat-table' is not extended. The current mechanism is focusing on the provisioning of external IP address and port set; other NAT-specific considerations are out of scope for this model."; } */ grouping map-instance { leaf id { mandatory true; type uint32; } leaf name { type string; } container map-rules { list map-rule { description "A set of parameters describing the mapping between an IPv4 prefix, IPv4 address or shared IPv4 address and an IPv6 prefix or address. Each domain uses a differe mapping rule set."; key "id"; leaf id { type uint8; } leaf map-rule-type { mandatory true; type enumeration { enum "BMR"; enum "FMR"; } description "The BMR and FMR share the rule format. BMR is used for a node to configure itself with IPv4 information retrived from the rule. FMR is designed for the in-domain 4-in-6 routing, used in mesh mode. A BMR can be FMR in some case. The DMR for map-t is defined separately."; } leaf rule-ipv6-prefix { type inet:ipv6-prefix; mandatory true; description "The Rule IPv6 prefix defined in the mapping rule."; } leaf rule-ipv4-prefix { type inet:ipv4-prefix; mandatory true; Sun, et al. Expires October 9, 2015 [Page 19] Internet-Draft YANG for softwire April 2015 description "The Rule IPv4 prefix defined in the mapping rule."; } container port-set { uses port-set { refine offset { default "6"; } } } leaf ea-len { mandatory true; type uint8; description "Embedded Address (EA) bits are the IPv4 EA-bits in the IPv6 address identify an IPv4 prefix/address (or part thereof) or a shared IPv4 address (or part thereof) and a port-set identifier. The length of the EA-bits is defined as part of a MAP rule for a MAP domain."; } } } } grouping traffic-stat { leaf sentPacket { type yang:zero-based-counter64; } leaf sentByte { type yang:zero-based-counter64; } leaf rcvdPacket { type yang:zero-based-counter64; } leaf rcvdByte { type yang:zero-based-counter64; } leaf droppedPacket { type yang:zero-based-counter64; } leaf droppedByte { type yang:zero-based-counter64; } } /* * Configuration Data Nodes */ Sun, et al. Expires October 9, 2015 [Page 20] Internet-Draft YANG for softwire April 2015 container softwire-config { description "The configuration data for Softwire instances. And the shared data describes the softwire data model which is common to all of the different softwire mechanisms, such as description."; leaf description { type string; description "A textual description of Softwire."; } container lwaftr { if-feature lwaftr; description "Indicate this instance supports the lwAFTR function. The instances advertise the lwaftr feature through the capability exchange mechanism when a NETCONF session is established."; leaf enable { type boolean; description "Enable/disable the lwAFTR function."; } container lwaftr-instances { description "A set of lwAFTRs to be configured."; list lwaftr-instance { key "id"; leaf id { type uint32; } leaf name { type string; description "The name for the lwaftr."; } leaf softwire-num-threshold { mandatory true; type uint32; description "The maximum number of tunnels that can be created on the lwAFTR."; } leaf tunnel-mtu { mandatory true; type uint32; description "The MTU for Lightweight 4over6 tunnel."; } leaf fragment-mru { Sun, et al. Expires October 9, 2015 [Page 21] Internet-Draft YANG for softwire April 2015 mandatory true; type uint16; description "The fragmentation MRU for Lightweight 4over6 tunnel."; } container binding-table { list binding-entry { key "binding-ipv6info"; uses binding-entry; } } } } } container lwb4 { if-feature lwb4; description "Indicate this instance supports the lwB4 function. The instances advertise the lwb4 feature through the capability exchange mechanism when a NETCONF session is established."; leaf enable { type boolean; description "Enable/disable the lwB4 function."; } container lwb4-instances { description "A set of lwB4s to be configured."; list lwb4-instance { key "binding-ipv6info"; leaf name { type string; description "The lwb4 name."; } leaf tunnel-mtu { mandatory true; type uint32; description "The MTU for Lightweight 4over6 tunnel."; } leaf fragment-mru { mandatory true; type uint16; description "The fragment MRU for Lightweight 4over6 tunnel."; } leaf b4-ipv6-addr-format { Sun, et al. Expires October 9, 2015 [Page 22] Internet-Draft YANG for softwire April 2015 type boolean; mandatory true; description "The format of lwB4 IPv6 address. If set to true, it indicates that the IPv6 source address of the lwB4 is constructed according to the description in [I-D.ietf-softwire-lw4over6]; if set to false, the lwB4 can use any /128 address from the assigned IPv6 prefix. [DISCUSS] Is this redudant? "; } uses binding-entry; } } } container map-e { if-feature map-e; description "Indicate the instances support the MAP-E function. The instances advertise the map-e feature through the capability exchange mechanism when a NETCONF session is established."; leaf enable { type boolean; default "true"; description "Enable/disable the MAP-E function."; } container map-e-instances { description "A set of MAP-E instances to be configured, applying to BRs and CEs."; list map-e-instance { key "id"; uses map-instance; leaf tunnel-mtu { mandatory true; type uint32; description "The MTU for MAP-E tunnel."; } leaf fragment-mru { mandatory true; type uint16; description "The fragment MRU for MAP-E tunnel."; } leaf br-ipv6-addr { type inet:ipv6-address; description Sun, et al. Expires October 9, 2015 [Page 23] Internet-Draft YANG for softwire April 2015 "The IPv6 address of the MAP-E BR."; } } } } container map-t { if-feature map-t; description "Indicate the instances support the MAP-T function. The instances advertise the map-t feature through the capability exchange mechanism when a NETCONF session is established."; leaf enable { type boolean; default "true"; description "Enable/disable the MAP-T function."; } container map-t-instances { description "A set of the MAP-T instances to be configured, applying to BRs and CEs."; list map-t-instance { key "id"; uses map-instance; leaf dmr-ipv6-prefix { type inet:ipv6-prefix; description "The IPv6 prefix of the MAP-T BR. "; } } } } } /* * Operational state Data Nodes */ container softwire-state { config false; description "The operational state data for Softwire instances. "; leaf description { type string; description "A textual description of the softwire instances."; } container lwaftr { Sun, et al. Expires October 9, 2015 [Page 24] Internet-Draft YANG for softwire April 2015 if-feature lwaftr; config false; description "Indicate this instance supports the lwAFTR function. The instances advertise the lwaftr feature through the capability exchange mechanism when a NETCONF session is established."; container lwaftr-instances { description "A set of lwAFTRs."; list lwaftr-instance { key "id"; leaf id { type uint32; } leaf name { type string; description "The name for this lwaftr."; } uses traffic-stat; leaf active-softwire-num { type uint32; description "The number of currently active tunnels on the lw4over6 instance."; } container binding-table { list binding-entry { key "binding-ipv6info"; leaf binding-ipv6info { mandatory true; type union { type inet:ipv6-address; type inet:ipv6-prefix; } description "The IPv6 information used to identify a binding entry. "; } leaf active { type boolean; description "Status of a specific tunnel."; } } } } } } Sun, et al. Expires October 9, 2015 [Page 25] Internet-Draft YANG for softwire April 2015 container lwb4 { if-feature lwb4; config false; description "Indicate this instance supports the lwB4 function. The instances advertise the lwb4 feature through the capability exchange mechanism when a NETCONF session is established."; container lwb4-instances { description "Status of the configured lwB4s."; list lwb4-instance { key "binding-ipv6info"; leaf name { type string; description "The lwb4 name."; } leaf binding-ipv6info { mandatory true; type union { type inet:ipv6-address; type inet:ipv6-prefix; } description "The IPv6 information used to identify a binding entry. "; } uses traffic-stat; } } } container map-e { if-feature map-e; config false; description "Indicate the instances support the MAP-E function. The instances advertise the map-e feature through the capability exchange mechanism when a NETCONF session is established."; container map-e-instances { description "Status of MAP-E instance(s)."; list map-e-instance { key "id"; leaf id { type int32; } leaf name { type string; description "The map-e instance name."; Sun, et al. Expires October 9, 2015 [Page 26] Internet-Draft YANG for softwire April 2015 } uses traffic-stat; } } } container map-t { if-feature map-t; config false; description "Indicate the instances support the MAP-T function. The instances advertise the map-t feature through the capability exchange mechanism when a NETCONF session is established."; container map-t-instances { description "Status of MAP-T instances."; list map-t-instance { key "id"; leaf id { type int32; } leaf name { type string; description "The map-t instance name."; } uses traffic-stat; } } } } /* * Notifications */ notification softwire-lwaftr-event { if-feature lwaftr; leaf lwaftr-id { mandatory true; type leafref { path "/softwire-state/lwaftr/lwaftr-instances/" + "lwaftr-instance/id"; } } leaf-list invalid-entry { type leafref { path "/softwire-config/lwaftr/lwaftr-instances/" + "lwaftr-instance[id=current()/../lwaftr-id]/" Sun, et al. Expires October 9, 2015 [Page 27] Internet-Draft YANG for softwire April 2015 + "binding-table/binding-entry/binding-ipv6info"; } description "Notify the client that a specific binding entry has been expired/invalid. The binding-ipv6info identifies an entry."; } leaf-list added-entry { type inet:ipv6-address; description "Notify the client that a binding entry has been added. The ipv6 address of that entry is the index. The client get other information from the lwaftr about the entry indexed by that ipv6 address. "; } leaf-list modified-entry { type leafref { path "/softwire-config/lwaftr/lwaftr-instances/" + "lwaftr-instance[id=current()/../lwaftr-id]/" + "binding-table/binding-entry/binding-ipv6info"; } } } notification softwire-lwb4-event { if-feature lwb4; leaf lwb4-binding-ipv6-addr-change { mandatory true; type inet:ipv6-address; description "The source tunnel IPv6 address of the lwB4. If 'b4-ipv6-addr-format' is false, or the lwb4's binding-ipv6-address changes for any reason, it SHOULD notify the NETCONF client."; } } notification softwire-map-e-event { if-feature map-e; leaf map-e-id { mandatory true; type leafref { path "/softwire-config/map-e/map-e-instances/map-e-instance/id"; } } leaf-list invalid-entry-id { type leafref { path "/softwire-config/map-e/map-e-instances/" Sun, et al. Expires October 9, 2015 [Page 28] Internet-Draft YANG for softwire April 2015 + "map-e-instance[id=current()/../map-e-id]/map-rules/" + "map-rule/id"; } } leaf-list added-entry { type uint32; } leaf-list modified-entry { type leafref { path "/softwire-config/map-e/map-e-instances/" + "map-e-instance[id=current()/../map-e-id]/map-rules/" + "map-rule/id"; } } } notification softwire-map-t-event { if-feature map-t; leaf map-t-id { mandatory true; type leafref { path "/softwire-config/map-t/map-t-instances/map-t-instance/id"; } } leaf-list invalid-entry-id { type leafref { path "/softwire-config/map-t/map-t-instances/" + "map-t-instance[id=current()/../map-t-id]/map-rules/" + "map-rule/id"; } } leaf-list added-entry { type uint32; } leaf-list modified-entry { type leafref { path "/softwire-config/map-t/map-t-instances/" + "map-t-instance[id=current()/../map-t-id]/map-rules/" + "map-rule/id"; } } } } Sun, et al. Expires October 9, 2015 [Page 29] Internet-Draft YANG for softwire April 2015 5. Example of Configure Lw4over6 Binding-Table The lwAFTR maintains an address binding table which contains the following 3-tuples: o IPv6 Address for a single lwB4 o Public IPv4 Address o Restricted port-set The entry has two functions: the IPv6 encapsulation of inbound IPv4 packets destined to the lwB4 and the validation of outbound IPv4-in- IPv6 packets received from the lwB4 for de-capsulation. Requirement: Add an entry that maintain the relationship between 3-tuples of lwB4 (2001::1) in binding-table, which on the lwAFTR (2001::2). The data value of this 3-tuples are '2001::1', '123.1.1.1' and '1234' respectively. Here is the example binding-table configuration xml: Sun, et al. Expires October 9, 2015 [Page 30] Internet-Draft YANG for softwire April 2015 // replace with IANA namespace when assigned. 2001::2 123.1.1.1 1234 2001::1 1 Figure 6: Lw4over6 Binding-Table Configuration XML 6. Security Considerations The YANG module defined in this memo is designed to be accessed via the NETCONF protocol [RFC6241]. The lowest NETCONF layer is the secure transport layer and the mandatory to implement secure transport is SSH [RFC6242]. The NETCONF access control model [RFC6536] provides the means to restrict access for particular NETCONF users to a pre-configured subset of all available NETCONF protocol operations and content. There are a number of data nodes defined in this YANG module which are writable/creatable/deletable (i.e. config true, which is the default). These data nodes may be considered sensitive or vulnerable in some network environments. Write operations (e.g. edit-config) to these data nodes without proper protection can have a negative effect on network operations. These are the subtrees and data nodes and their sensitivity/vulnerability: Sun, et al. Expires October 9, 2015 [Page 31] Internet-Draft YANG for softwire April 2015 subtrees and data nodes and state why they are sensitive Some of the readable data nodes in this YANG module may be considered sensitive or vulnerable in some network environments. It is thus important to control read access (e.g. via get, get-config or notification) to these data nodes. These are the subtrees and data nodes and their sensitivity/vulnerability: subtrees and data nodes and state why they are sensitive 7. IANA Considerations A registry for standard YANG modules shall be set up. This document registers one URI for the YANG XML namespace in the IETF XML registry [RFC3688]. URI: urn:ietf:params:xml:ns:yang:softwire 8. Acknowledgements The authors would like to thank Lishan Li, Bert Wijnen and Giles Heron for their contributions to this work. 9. References 9.1. Normative References [I-D.ietf-softwire-lw4over6] Cui, Y., Qiong, Q., Boucadair, M., Tsou, T., Lee, Y., and I. Farrer, "Lightweight 4over6: An Extension to the DS- Lite Architecture", draft-ietf-softwire-lw4over6-13 (work in progress), November 2014. [I-D.ietf-softwire-map] Troan, O., Dec, W., Li, X., Bao, C., Matsushima, S., Murakami, T., and T. Taylor, "Mapping of Address and Port with Encapsulation (MAP)", draft-ietf-softwire-map-13 (work in progress), March 2015. [I-D.ietf-softwire-map-t] Li, X., Bao, C., Dec, W., Troan, O., Matsushima, S., and T. Murakami, "Mapping of Address and Port using Translation (MAP-T)", draft-ietf-softwire-map-t-08 (work in progress), December 2014. [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. Sun, et al. Expires October 9, 2015 [Page 32] Internet-Draft YANG for softwire April 2015 [RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688, January 2004. [RFC6020] Bjorklund, M., "YANG - A Data Modeling Language for the Network Configuration Protocol (NETCONF)", RFC 6020, October 2010. [RFC6241] Enns, R., Bjorklund, M., Schoenwaelder, J., and A. Bierman, "Network Configuration Protocol (NETCONF)", RFC 6241, June 2011. [RFC6242] Wasserman, M., "Using the NETCONF Protocol over Secure Shell (SSH)", RFC 6242, June 2011. [RFC6536] Bierman, A. and M. Bjorklund, "Network Configuration Protocol (NETCONF) Access Control Model", RFC 6536, March 2012. 9.2. Informative References [RFC6991] Schoenwaelder, J., "Common YANG Data Types", RFC 6991, July 2013. Authors' Addresses Qi Sun Tsinghua University Beijing 100084 P.R. China Phone: +86-10-6278-5822 Email: sunqi@csnet1.cs.tsinghua.edu.cn Hao Wang Tsinghua University Beijing 100084 P.R. China Phone: +86-10-6278-5822 Email: wangh13@mails.tsinghua.edu.cn Sun, et al. Expires October 9, 2015 [Page 33] Internet-Draft YANG for softwire April 2015 Yong Cui Tsinghua University Beijing 100084 P.R. China Phone: +86-10-6260-3059 Email: yong@csnet1.cs.tsinghua.edu.cn Ian Farrer Deutsche Telekom AG CTO-ATI,Landgrabenweg 151 Bonn, NRW 53227 Germany Email: ian.farrer@telekom.de Mohamed Boucadair France Telecom Rennes 35000 France Email: mohamed.boucadair@orange.com Rajiv Asati Cisco Systems, Inc. 7025 Kit Creek Rd. RTP, NC 27709 USA Email: Rajiva@cisco.com Sun, et al. Expires October 9, 2015 [Page 34]