--- 1/draft-ietf-lpwan-schc-yang-data-model-01.txt 2020-02-28 06:13:17.457375273 -0800 +++ 2/draft-ietf-lpwan-schc-yang-data-model-02.txt 2020-02-28 06:13:17.509376588 -0800 @@ -1,19 +1,19 @@ lpwan Working Group A. Minaburo Internet-Draft Acklio Intended status: Standards Track L. Toutain -Expires: July 26, 2020 Institut MINES TELECOM; IMT Atlantique - January 23, 2020 +Expires: August 31, 2020 Institut MINES TELECOM; IMT Atlantique + February 28, 2020 Data Model for Static Context Header Compression (SCHC) - draft-ietf-lpwan-schc-yang-data-model-01 + draft-ietf-lpwan-schc-yang-data-model-02 Abstract This document describes a YANG data model for the SCHC (Static Context Header Compression) compression and fragmentation rules. Status of This Memo This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. @@ -21,21 +21,21 @@ 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 July 26, 2020. + This Internet-Draft will expire on August 31, 2020. Copyright Notice Copyright (c) 2020 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (https://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents @@ -55,29 +55,29 @@ 2.4. Field position . . . . . . . . . . . . . . . . . . . . . 7 2.5. Direction Indicator . . . . . . . . . . . . . . . . . . . 7 2.6. Target Value . . . . . . . . . . . . . . . . . . . . . . 8 2.7. Matching Operator . . . . . . . . . . . . . . . . . . . . 9 2.7.1. Matching Operator arguments . . . . . . . . . . . . . 10 2.8. Compression Decompresison Actions . . . . . . . . . . . . 10 2.8.1. Compression Decompression Action arguments . . . . . 12 3. Rule definition . . . . . . . . . . . . . . . . . . . . . . . 12 3.1. Compression rule . . . . . . . . . . . . . . . . . . . . 14 3.1.1. Compression context representation. . . . . . . . . . 14 - 3.1.2. Rule definition . . . . . . . . . . . . . . . . . . . 16 + 3.1.2. Rule definition . . . . . . . . . . . . . . . . . . . 15 3.2. Fragmentation rule . . . . . . . . . . . . . . . . . . . 16 3.3. YANG Tree . . . . . . . . . . . . . . . . . . . . . . . . 17 - 4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 17 - 5. Security considerations . . . . . . . . . . . . . . . . . . . 17 - 6. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 18 - 7. YANG Module . . . . . . . . . . . . . . . . . . . . . . . . . 18 - 8. Normative References . . . . . . . . . . . . . . . . . . . . 18 - Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 18 + 4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 19 + 5. Security considerations . . . . . . . . . . . . . . . . . . . 19 + 6. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 19 + 7. YANG Module . . . . . . . . . . . . . . . . . . . . . . . . . 19 + 8. Normative References . . . . . . . . . . . . . . . . . . . . 33 + Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 33 1. Introduction 2. SCHC rules SCHC is a compression and fragmentation mechanism for constrained networks defined in [I-D.ietf-lpwan-ipv6-static-context-hc] it is based on a static context shared by two entities at the boundary this contrained network. Draft [I-D.ietf-lpwan-ipv6-static-context-hc] provides an abstract representation of the rules used either for @@ -199,21 +199,21 @@ Figure 2 gives an example of field ID identityref definitions. The base identity is field-id-base-type, and field id are derived for it. The naming convention is "fid" followed by the protocol name and the field name. The yang model in annex gives the full definition of the field ID for [I-D.ietf-lpwan-ipv6-static-context-hc] and [I-D.ietf-lpwan-coap-static-context-hc]. -The type associated to this identity is field-id-type (cf. {{Fig-field-id-type}}) + The type associated to this identity is field-id-type (cf. Figure 3) typedef field-id-type { description "Field ID generic type."; type identityref { base field-id-base-type; } } Figure 3: Definition of indentityref for field IDs @@ -530,110 +530,163 @@ leaf field-position { mandatory true; type uint8; } leaf direction-indicator { mandatory true; type schc-id:direction-indicator-type; } list target-values { key position; - uses target-values-struct; } leaf mo { mandatory true; type schc-id:matching-operator-type; } - // /!\ Not always good, it allows to give several arguments to a MO, but - // theses arguments are only int or strings, cannot be arrays. Is it necessary? list mo-value { key position; uses target-values-struct; } leaf cda { mandatory true; - type schc-id:cda-type; + type schc-id:comp-decomp-action-type; } list cda-value { key position; uses target-values-struct; } } Figure 14: Definition of a compression entry 3.1.2. Rule definition A compression rule is a list of entries. grouping compression-content { list entry { - key "field-id field-position direction-indicator"; // field-position direction-indicator"; + key "field-id field-position direction-indicator"; uses compression-rule-entry; } } Figure 15: Definition of a compression rule - To identify a specific entry Field ID, position and direction is + To identify a specific entry Field ID, position and direction are needed. 3.2. Fragmentation rule - TBD + Parameters for fragmentation are defined in Annex D of + [I-D.ietf-lpwan-ipv6-static-context-hc]. Two new types are defined + for Ack on Error acknowlement behavior (ack-behavior-type) and the + RCS algorithm (RCS-algorithm-type). grouping fragmentation-content { + leaf direction { + type schc-id:direction-indicator-type; + description "should be up or down"; + } + leaf dtagsize { type uint8; + description "size in bit of the DTag field"; } leaf wsize { type uint8; + description "size in bit of the window field"; } leaf fcnsize { type uint8; + description "size in bit of the FCN field"; + } + leaf RCS-algorithm { + type RCS-algorithm-type; + default schc-id:RFC8724-RCS; + description "Algoritm used for RCS"; + } + leaf maximum-window-size { + type uint16; + description "by default 2^wsize - 1"; + } + + leaf retransmission-timer { + type uint64; + description "duration in seconds of the retransmission timer"; // Check the units + } + + leaf inactivity-timer { + type uint64; + description "duration is seconds of the inactivity timer"; // check units + } + + leaf max-ack-requests { + type uint8; } + + leaf maximum-packet-size { + type uint16; + mandatory true; + default 1280; + description "When decompression is done, packet size must not strictly exceed this limit in Bytes"; + } + choice mode { case no-ack; case ack-always; case ack-on-error { - leaf ack-method { - type enumeration { - enum afterAll0; - enum afterAll1; - enum always; + leaf tile-size { + type uint8; + description "size in bit of tiles"; + } + leaf tile-in-All1 { + type boolean; + description "When true, sender and receiver except a tile in All-1 frag"; } + leaf ack-behavior { + type schc-id:ack-behavior-type; + mandatory true; } + } } } Figure 16: Definition of a fragmentation rule 3.3. YANG Tree - module: schc +--rw schc +--rw version? uint64 +--rw rule* [rule-id rule-length] +--rw rule-id uint32 +--rw rule-length uint8 +--rw (nature)? +--:(fragmentation) + | +--rw direction? schc-id:direction-indicator-type | +--rw dtagsize? uint8 | +--rw wsize? uint8 | +--rw fcnsize? uint8 - | +--rw (mode)? + | +--rw RCS-algorithm? RCS-algorithm-type + | +--rw maximum-window-size? uint16 + | +--rw retransmission-timer? uint64 + | +--rw inactivity-timer? uint64 + | +--rw max-ack-requests? uint8 + | +--rw maximum-packet-size uint16 + | +--rw (mode) | +--:(no-ack) | +--:(ack-always) | +--:(ack-on-error) - | +--rw ack-method? enumeration + | +--rw tile-size? uint8 + | +--rw tile-in-All1? boolean + | +--rw ack-behavior schc-id:ack-behavior-type +--:(compression) +--rw entry* [field-id field-position direction-indicator] +--rw field-id schc-id:field-id-type +--rw field-length schc-id:field-length-type +--rw field-position uint8 +--rw direction-indicator schc-id:direction-indicator-type +--rw target-values* [position] | +--rw value? union | +--rw position uint16 +--rw mo schc-id:matching-operator-type @@ -656,20 +709,695 @@ This document does not have any more Security consideration than the ones already raised on [I-D.ietf-lpwan-ipv6-static-context-hc] 6. Acknowledgements The authors would like to thank Dominique Barthel, Carsten Bormann, Alexander Pelov. 7. YANG Module + Currently the data model is split into two parts. The first one is + dedicated to SCHC identifiers and the second one contains the rules + definition. The goal is to allow some stabilities in the rule + identifiers if new SCHC identfiers are added. When the model will be + stable, these two files will be merged. + + file schc-id@2020-02-28.yang +module schc-id{ + yang-version "1"; + namespace "urn:ietf:lpwan:schc:schc-id"; + prefix "schc-id"; + + description + "Identifiers used in SCHC data model."; + + revision 2020-02-28 { + description "Add fragmentation identifiers"; + } + revision 2020-02-11 { + description "Clean up"; + } + revision 2020-01-07 { + description "First version of the SCHC identifiers"; + } + +// ------------------------- +// Field ID type definition +//-------------------------- + +// generic value TV definition + + identity field-id-base-type { + description "Field ID with SID"; + } + + identity fid-ipv6-version { + base field-id-base-type; + description "IPv6 version field from RFC8200"; + } + + identity fid-ipv6-trafficclass { + base field-id-base-type; + description "IPv6 Traffic Class field from RFC8200"; + } + + identity fid-ipv6-trafficclass-ds { + base field-id-base-type; + description "IPv6 Traffic Class field from RFC8200, + DiffServ field from RFC3168"; + } + + identity fid-ipv6-trafficclass-ecn { + base field-id-base-type; + description "IPv6 Traffic Class field from RFC8200, + ECN field from RFC3168"; + } + + identity fid-ipv6-flowlabel { + base field-id-base-type; + description "IPv6 Flow Label field from RFC8200"; + } + + identity fid-ipv6-payloadlength { + base field-id-base-type; + description "IPv6 Payload Length field from RFC8200"; + } + + identity fid-ipv6-nextheader { + base field-id-base-type; + description "IPv6 Next Header field from RFC8200"; + } + + identity fid-ipv6-hoplimit { + base field-id-base-type; + description "IPv6 Next Header field from RFC8200"; + } + + identity fid-ipv6-devprefix { + base field-id-base-type; + description "correspond either to the source address or the desdination + address prefix of RFC 8200. Depending if it is respectively + a uplink or an downklink message."; + } + + identity fid-ipv6-deviid { + base field-id-base-type; + description "correspond either to the source address or the desdination + address prefix of RFC 8200. Depending if it is respectively + a uplink or an downklink message."; + } + + identity fid-ipv6-appprefix { + base field-id-base-type; + description "correspond either to the source address or the desdination + address prefix of RFC 768. Depending if it is respectively + a downlink or an uplink message."; + } + + identity fid-ipv6-appiid { + base field-id-base-type; + description "correspond either to the source address or the desdination + address prefix of RFC 768. Depending if it is respectively + a downlink or an uplink message."; + } + + identity fid-udp-dev-port { + base field-id-base-type; + description "UDP length from RFC 768"; + } + + identity fid-udp-app-port { + base field-id-base-type; + description "UDP length from RFC 768"; + } + + identity fid-udp-length { + base field-id-base-type; + description "UDP length from RFC 768"; + } + + identity fid-udp-checksum { + base field-id-base-type; + description "UDP length from RFC 768"; + } + + identity fid-coap-version { + base field-id-base-type; + description "CoAP version from RFC 7252"; + + } + + identity fid-coap-type { + base field-id-base-type; + description "CoAP type from RFC 7252"; + } + + identity fid-coap-tkl { + base field-id-base-type; + description "CoAP token length from RFC 7252"; + } + + identity fid-coap-code { + base field-id-base-type; + description "CoAP code from RFC 7252"; + } + + identity fid-coap-code-class { + base field-id-base-type; + description "CoAP code from RFC 7252"; + } + + identity fid-coap-code-detail { + base field-id-base-type; + description "CoAP code from RFC 7252"; + } + + identity fid-coap-mid { + base field-id-base-type; + description "CoAP message ID from RFC 7252"; + } + + identity fid-coap-token { + base field-id-base-type; + description "CoAP token from RFC 7252"; + } + + identity fid-coap-option-if-match { + base field-id-base-type; + description "CoAP option If-Match from RFC 7252"; + } + + identity fid-coap-option-uri-host { + base field-id-base-type; + description "CoAP option URI-Host from RFC 7252"; + } + + identity fid-coap-option-etag { + base field-id-base-type; + description "CoAP option Etag from RFC 7252"; + } + + identity fid-coap-option-if-none-match { + base field-id-base-type; + description "CoAP option if-none-match from RFC 7252"; + } + + identity fid-coap-option-observe { + base field-id-base-type; + description "CoAP option Observe from RFC 7641"; + } + + identity fid-coap-option-uri-port { + base field-id-base-type; + description "CoAP option Uri-Port from RFC 7252"; + } + + identity fid-coap-option-location-path { + base field-id-base-type; + description "CoAP option Location-Path from RFC 7252"; + } + + identity fid-coap-option-uri-path { + base field-id-base-type; + description "CoAP option Uri-Path from RFC 7252"; + } + + identity fid-coap-option-content-format { + base field-id-base-type; + description "CoAP option Content Format from RFC 7252"; + } + + identity fid-coap-option-max-age { + base field-id-base-type; + description "CoAP option Max-Age from RFC 7252"; + } + + identity fid-coap-option-uri-query { + base field-id-base-type; + description "CoAP option Uri-Query from RFC 7252"; + } + + identity fid-coap-option-accept { + base field-id-base-type; + description "CoAP option Max-Age from RFC 7252"; + } + identity fid-coap-option-location-query { + base field-id-base-type; + description "CoAP option Location-Query from RFC 7252"; + } + + identity fid-coap-option-block2 { + base field-id-base-type; + description "CoAP option Block2 from RFC 7959"; + } + + identity fid-coap-option-block1 { + base field-id-base-type; + description "CoAP option Block1 from RFC 7959"; + } + + identity fid-coap-option-size2 { + base field-id-base-type; + description "CoAP option size2 from RFC 7959"; + } + + identity fid-coap-option-proxy-uri { + base field-id-base-type; + description "CoAP option Proxy-Uri from RFC 7252"; + } + + identity fid-coap-option-proxy-scheme { + base field-id-base-type; + description "CoAP option Proxy-scheme from RFC 7252"; + } + + identity fid-coap-option-size1 { + base field-id-base-type; + description "CoAP option Size1 from RFC 7252"; + } + + identity fid-coap-option-no-response { + base field-id-base-type; + description "CoAP option No response from RFC 7967"; + } + + identity fid-coap-option-end-option { + base field-id-base-type; + description "CoAP End Option from RFC 7967"; + } + +//---------------------------------- +// Field Length type definition +//---------------------------------- + + identity field-length-base-type { + description "used to extend field length functions"; + } + + identity fl-variable { + base field-length-base-type; + description "residue length in Byte is sent"; + } + + identity fl-token-length { + base field-length-base-type; + description "residue length in Byte is sent"; + } + +//--------------------------------- +// Direction Indicator type +//--------------------------------- + + identity direction-indicator-base-type { + description "used to extend field length functions"; + } + + identity di-bidirectional { + base direction-indicator-base-type; + description "Direction Indication of bi directionality"; + } + + identity di-up { + base direction-indicator-base-type; + description "Direction Indication of upstream"; + } + + identity di-down { + base direction-indicator-base-type; + description "Direction Indication of downstream"; + } + +//---------------------------------- +// Matching Operator type definition +//---------------------------------- + + identity matching-operator-base-type { + description "used to extend Matching Operators with SID values"; + } + + identity mo-equal { + base matching-operator-base-type; + description "SCHC draft"; + } + + identity mo-ignore { + base matching-operator-base-type; + description "SCHC draft"; + } + + identity mo-msb { + base matching-operator-base-type; + description "SCHC draft"; + } + + identity mo-matching { + base matching-operator-base-type; + description "SCHC draft"; + } + +//------------------------------ +// CDA type definition +//------------------------------ + + identity compression-decompression-action-base-type; + + identity cda-not-sent { + base compression-decompression-action-base-type; + description "from SCHC draft"; + } + + identity cda-value-sent { + base compression-decompression-action-base-type; + description "from SCHC draft"; + } + + identity cda-lsb { + base compression-decompression-action-base-type; + description "from SCHC draft"; + } + + identity cda-mapping-sent { + base compression-decompression-action-base-type; + description "from SCHC draft"; + } + + identity cda-compute-length { + base compression-decompression-action-base-type; + description "from SCHC draft"; + + } + + identity cda-compute-checksum { + base compression-decompression-action-base-type; + description "from SCHC draft"; + } + + identity cda-deviid { + base compression-decompression-action-base-type; + description "from SCHC draft"; + } + + identity cda-appiid { + base compression-decompression-action-base-type; + description "from SCHC draft"; + } + +// -- type definition + + typedef field-id-type { + description "Field ID generic type."; + type identityref { + base field-id-base-type; + } + } + + typedef field-length-type { + type union { + type int64; /* positive length */ + type identityref { /* function */ + base field-length-base-type; + } + } + } + + typedef direction-indicator-type { + type identityref { + base direction-indicator-base-type; + } + } + + typedef matching-operator-type { + type identityref { + base matching-operator-base-type; + } + } + + typedef comp-decomp-action-type { + type identityref { + base compression-decompression-action-base-type; + } + } + +// -- fragmentation types + + identity ack-behavior-base-type { + description "type to define when to send an Acknowledgment message"; + } + + identity ack-behavior-after-All0 { + description "fragmentor expect Ack after sending All0 fragment."; + base ack-behavior-base-type; + } + + identity ack-behavior-after-All1 { + description "fragmentor expect Ack after sending All1 fragment."; + base ack-behavior-base-type; + } + + identity ack-behavior-after-Always { + description "fragmentor expect Ack after sending every fragment."; + base ack-behavior-base-type; + } + + typedef ack-behavior-type { + type identityref { + base ack-behavior-base-type; + } + } + +// -- fragmentation types + + identity RCS-algorithm-base-type { + description "identify which algorithm is used to compute RSC. + The algorithm defines also the size if the RSC field."; + } + + identity RFC8724-RCS { + description "CRC 32 defined as default RCS in RFC8724."; + base RCS-algorithm-base-type; + } + + typedef RCS-algorithm-type { + type identityref { + base RCS-algorithm-base-type; + } + + } + +} + + + Figure 18 + + file schc@2020-02-28.yang +module schc{ + yang-version "1"; + namespace "urn:ietf:lpwan:schc:rules-description"; + prefix "schc"; + + import schc-id { + prefix "schc-id"; + } + + description + "Generic Data model for Static Context Header Compression Rule for SCHC, + based on draft-ietf-lpwan-ipv6-static-context-hc-18. Include compression + rules and fragmentation rules."; + + revision 2020-02-28 { + description "Add Fragmentation parameters"; + } + + revision 2020-01-23 { + description "Modified TV with binary and union"; + } + + revision 2020-01-07 { + description "First version of the YANG model"; + } + +// -------- RULE DEFINITION ------------ + + grouping target-values-struct { + leaf value { + type union { + type binary; + type string; + } + } + leaf position { + type uint16; + } + + } + + grouping compression-rule-entry { + leaf field-id { + mandatory true; + type schc-id:field-id-type; + } + leaf field-length { + mandatory true; + type schc-id:field-length-type; + } + leaf field-position { + mandatory true; + type uint8; + } + leaf direction-indicator { + mandatory true; + type schc-id:direction-indicator-type; + } + list target-values { + key position; + uses target-values-struct; + } + leaf mo { + mandatory true; + type schc-id:matching-operator-type; + } + list mo-value { + key position; + uses target-values-struct; + } + leaf cda { + mandatory true; + type schc-id:comp-decomp-action-type; + } + list cda-value { + key position; + uses target-values-struct; + } + } + + grouping fragmentation-content { + leaf direction { + type schc-id:direction-indicator-type; + description "should be up or down"; + } + + leaf dtagsize { + type uint8; + description "size in bit of the DTag field"; + } + leaf wsize { + type uint8; + description "size in bit of the window field"; + } + leaf fcnsize { + type uint8; + description "size in bit of the FCN field"; + } + leaf RCS-algorithm { + type RCS-algorithm-type; + default schc-id:RFC8724-RCS; + description "Algoritm used for RCS"; + } + leaf maximum-window-size { + type uint16; + description "by default 2^wsize - 1"; + } + + leaf retransmission-timer { + type uint64; + description "duration in seconds of the retransmission timer"; // Check the units + } + + leaf inactivity-timer { + type uint64; + description "duration is seconds of the inactivity timer"; // check units + } + + leaf max-ack-requests { + type uint8; + } + + leaf maximum-packet-size { + type uint16; + mandatory true; + default 1280; + description "When decompression is done, packet size must not strictly exceed this limit in Bytes"; + } + + choice mode { + mandatory true; + case no-ack; + case ack-always; + case ack-on-error { + leaf tile-size { + type uint8; + description "size in bit of tiles"; + } + leaf tile-in-All1 { + type boolean; + description "When true, sender and receiver except a tile in All-1 frag"; + } + leaf ack-behavior { + type schc-id:ack-behavior-type; + mandatory true; + } + + } + } + } + + grouping compression-content { + list entry { + key "field-id field-position direction-indicator"; + uses compression-rule-entry; + } + } + +// Define rule ID. Rule ID is composed of a RuleID value and a Rule ID Length + + grouping rule-id-type { + leaf rule-id { + type uint32; + description "rule ID value, this value must be unique combined with the length"; + } + leaf rule-length { + type uint8 { + range 0..32; + } + description "rule ID length in bits, value 0 is for implicit rules"; + } + } + +// SCHC table for a specific device. + + container schc { + leaf version{ + type uint64; + mandatory false; + description "used as an indication for versioning"; + } + list rule { + key "rule-id rule-length"; + uses rule-id-type; + choice nature { + case fragmentation { + uses fragmentation-content; + } + case compression { + uses compression-content; + } + } + } + } + +} + + + + Figure 19 + 8. Normative References [I-D.ietf-lpwan-coap-static-context-hc] Minaburo, A., Toutain, L., and R. Andreasen, "LPWAN Static Context Header Compression (SCHC) for CoAP", draft-ietf- lpwan-coap-static-context-hc-12 (work in progress), December 2019. [I-D.ietf-lpwan-ipv6-static-context-hc] Minaburo, A., Toutain, L., Gomez, C., Barthel, D., and J.