LISP Working Group S. Barkai Internet-Draft B. Fernandez-Ruiz Intended status: Experimental O. Serfaty Expires: October 4, 2019 Nexar Inc. A. Rodriguez-Natal F. Maino Cisco Systems A. Cabellos-Aparicio J. Paillissé Vilanova Technical University of Catalonia D. Farinacci lispers.net May 4 2019 Network-Hexagons, an H3-LISP Based Mobility Network draft-barkai-lisp-nexagon-03 Abstract This document specifies combined use of H3 and LISP for mobility-networks: - Enabling real-time tile-by-tile localized-annotation of road-conditions - Sharing of road annotations: hazards, blockages, maintenance, furniture - Between MobilityClients producing and consuming road-state information - Using in-network tile-state addressable-indexed-maintained in H3Servers. Status of This Memo This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at https://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." This Internet-Draft will expire on October 4, 2019. Copyright Notice Copyright (c) 2019 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (https://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 2. Requirements Language . . . . . . . . . . . . . . . . . . . . 3 3. Definition of Terms . . . . . . . . . . . . . . . . . . . . . 3 4. Deployment Assumptions . . . . . . . . . . . . . . . . . . . 4 5. Mobility Clients-Network-Servers . . . . . . . . . . . . . . 4 6. Mobility Unicast-Multicast . . . . . . . . . . . . . . . . . 5 7. Security Considerations . . . . . . . . . . . . . . . . . . . 6 8. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 6 9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 6 10. Normative References . . . . . . . . . . . . . . . . . . . . 8 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 9 1. Introduction (1) The Locator/ID Separation Protocol (LISP) [RFC6830] splits current IP addresses in two different namespaces, Endpoint Identifiers (EIDs) and Routing Locators (RLOCs). LISP uses a map-and-encap approach that relies on (1) a Mapping System (distributed database) that stores and disseminates EID-RLOC mappings and on (2) LISP tunnel routers (xTRs) that encapsulate and decapsulate data packets based on the content of those mappings. (2) H3 is a geospatial indexing system using a hexagonal grid that can be (approximately) subdivided into finer and finer hexagonal grids, combining the benefits of a hexagonal grid with hierarchical subdivisions. H3 supports sixteen resolutions. Each finer resolution has cells with one seventh the area of the coarser resolution. Hexagons cannot be perfectly subdivided into seven hexagons, so the finer cells are only approximately contained within a parent cell. Each cell is identified by a 64bit HID. (3) The Berkeley Deep Drive (BDD) Industry Consortium investigates state-of- the-art technologies in computer vision and machine learning for automotive applications, and, for taxonomy of published automotive scene classification. These standards are combined to create in-network-state reflecting the condition of each one-square-meter (1sqm) hexagon road-tile. The lisp network maps traffic between MobilityClients endpoint identifiers (EID), and, hex-id (HID to EID) addressable tile-states. States maintained by H3Servers. The H3-LISP mobility network bridges timing-location gaps between the production and consumption of information by MobilityClients: - vision, sensory, LIADR, AI information producers - apps/smart-infrastructure information consumers And is achieved by mobility in-network addressable-state indirection. This capability addresses a key issue in todays' vehicle to vehicle (v2v) networking, where observed hazards are expected to be "hot-potato-tossed" between vehicles without clear convergence. For example, when a vehicle experiences a sudden highway slow-down, by "seeing" breaks light-up in-front, an-or by accelerometer, there is no clear way for it to share this annotation with vehicles which are 20-30 seconds away, potentially preventing major pile-ups, especially on icy or poor visibility conditions. Or, when a vehicle crosses an intersection, observing opposite=lane-obstruction - construction, double-park, commercial loading / un-loading, garbage truck, or stopped school -bus - there is no clear way for it to alert vehicles turning in to that lane as it drives straight on its away. The H3-LISP mobility network solves this limitation of direct vehicle to vehicle communication by MobilityClients (EIDs) communicating with in-network road-tile in-network states. These states are aggregated-maintained by LISP EID addressable H3Servers. An important set of use-cases involves propagation of condition information to MobilityClients to provide drivers heads-up alerts on hazards and obstacles beyond line of sight: over traffic, around blocks, far-side-junction, beyond turns and surface-curvatures. This highlights the importance of networks in providing road-safety greater then any isolated or autonomous vehicle safety technology. To summarize the H3-LISP solution outline: (1) Partition: Geo-spatial H3.r15 (1sqm) road-tiles indexed by 64bit HIDs (2) State: geo-tile-state values complied to 64bit condition representation (3) Aggregation: H3Servers use H3.r9 resolution to group H3.r15 road-tiles (4) Channels: H3Servers function multicast aggregated H3.r15 state updates (5) Scale: H3Servers are distributed for in-network for latency-throughput (6) Mapped: An overlay tunneled-network routes the mobility-network traffic (7) Signal-free: Tunneled overlay is used to map-register for mcast channels (8) Access: Tunnels used between MobilityClients/H3Servers <> and LISP edge (9) Access: ClientXTRs/ServerXTRs tunnel traffic to-from the LISP EdgeRTRs (10) Control: EdgeRTRs register-resolve identity-location as well as mcast |-0-|-1-|-2-|-3-|-4-|-5-|-6-|-7-|-8-|-9-|-A-|-B-|-C-|-D-|-E-|-F-| | H3 Hexagon ID Key | |-0-|-1-|-2-|-3-|-4-|-5-|-6-|-7-|-8-|-9-|-A-|-B-|-C-|-D-|-E-|-F-| | H3 Hexagon State-Value | |---------------------------------------------------------------| ___ ___ H3Servers ___ / \ H3Servers ___ / \ ___ / | H3.r9 | ___ / | H3.r9 | / | H3.r9 \ ___ / / | H3.r9 \ ___ / | H3.r9 \ ___ / sXTR | H3.r9 \ ___ / sXTR \ ___ / sXTR | \ ___ / sXTR | sXTR | | sXTR | | | | | | | | | | | | | | + - - + - - EdgeRTR EdgeRTR - + - + - - + || ( ( -- || ( ) ( Nexagon ) ( H3-LISP Based ) ( Mobility Network ) (( ) || (( __ -- || || || || || = = = = = = = = = = = || || EdgeRTR EdgeRTR .. .. .. .. .. .. .. .. ((((|)))) ((((|)))) ((((|)))) ((((|)))) /|\ RAN /|\ /|\ RAN /|\ .. .. .. ___ ___ ___ .. .. .............. / \/ \/ \ << cXTR::MobilityClient .. - - - - - - - - H3.r15 H3.r15 H3.r15 - - - - - - - MobilityClient::cXTR >> \ ___ /\ ___ /\ ___ /.......... cXTR: ClientXTR tunnel encapsulation through access network to LISP Edge sXTR: ServerXTR tunnel encapsulation through cloud network to LISP Edge Each H3.r9 hexagon is a server with corresponding H3 ID. Bound to that server is a LISP xTR, called a ServerXTR, resident to deliver encapsulated packets to and from the H3Server and the LISP Edge. EdgeRTRs are used to re-tunnel packets from MobilityClients to that H3Server. Each H3Server HID is also a source multicast address for updating MobilityClients as to the state of the H3.r15 tiles contained in the H3.r9 H3Server. 2. 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]. 3. Definition of Terms H3Server: Is a server process which maintains state in part of a H3 geo-spatial grid. H3Server is responsible for a single hexagon in a given resolution. In this specification each H3Server is responsible for one H3.r9 hexagon. An H3Server can roam between hosting locations for maintenance or failover, it will always have the same EID IPv6 address based on its HID hexagon ID. The H3Server application sends unicast and multicast packets from its EID. It has a light-weight LISP protocol stack to tunnel packets aka ServerXTR. H3Server EID: Is an IPv6 EID that contains the H3 64-bit address numbering scheme. See IANA consideration for details. ServerXTR: Is a light-weight LISP protocol stack implementation that co-exists with an H3Server process. When the server roams, the xTR roams with it. The ServerXTR encapsulates and decapsulates packets to/from EdgeRTRs. MobilityClient: Is a roaming application that may be resident as part of an automobile, as part of a navigation application, part of municipal, state, of federal government command and control application, or part of live street view consumer type of application. It has a light-weight LISP protocol stack to tunnel packets aka ClientXTR. MobilityClient EID: Is the IPv6 EID used by the Mobility Client applications to source packets. The destination of such packets are only H3Server EIDs. The EID format is opaque and is assigned as part of the MobilityClient network as-a-service (NaaS) authorization. ClientXTR: Is the light-weight LISP protocol stack implementation that is co-located with the Mobility Client application. It encapsulates packets sourced by applications to EdgeRTRs and decapsulates packets from EdgeRTRs. EdgeRTR: Is the core scale and structure of the LISP mobility network. LISP RTRs decapsulate packets from ClientXTRs and ServerXTRs and re-encapsulates packets to ServerXTRs and ClientXTRs. The EdgeRTRs glean H3Server EIDs and glean MobilityClient EIDs when it decapsulates packets. EdgeRTRs store H3Server EIDs and their own RLOC of where the H3Server is currently reachable from in the map-cache. These mappings are registered to the LISP mapping system so other EdgeRTRs know where to encapsulate for such EIDs. 4. Deployment Assumptions The specification described in this document makes the following deployment assumptions: (1) Unique 64-bit HID is associated with each H3 geo-spatial tile (2) MobilityClients and H3Servers share this well known index (3) A 64-bit BDD state value is associated with each H3 tile (4) Tile state is compiled 16 fields of 4-bits or 16 enums |-0-|-1-|-2-|-3-|-4-|-5-|-6-|-7-|-8-|-9-|-A-|-B-|-C-|-D-|-E-|-F-| 0123012301230123012301230123012301230123012301230123012301230123 A MobilityClient which needs to use an H3-LISP mobility overlay network - instantiates a ClientXTR. It leverages DNS resolution to find EdgeRTR(s) in order to home to. ClientXTR is provisioned with an anycast address for the DNS resolvers, that help with the EdgeRTR discovery. The ClientXTR uses these anycasted DNS resolvers to resolve a query that includes the ClientXTR’s current H3 index at resolution 9 (e.g. h3res9.example.net). To find its current H3.res9 index, the ClientXTR first translates its current geo- location to an H3 index (e.g. gps snap-to-res9-hex).As a response to the query including the H3.res9 index of the ClientXTR, the DNS resolver will return the IP address of the Edge RTR that the ClientXTR can use to home to the H3-LISP mobility overlay. The EdgeRTR discovery by the ClientXTR performed via DNS resolution so that: 1) EdgeRTRs are not tightly coupled to H3.r9 areas for easy load-balance 2) Mobility Clients do not need to constantly update EdgeRTR when it roams In that sense, the same EdgeRTR may serve several H3.r9 areas for smooth ride continuity, and, several EdgeRTRs may load balance a H3.r9 area with high density of originating MobilityClient rides. When a MobilityClient::ClientXTR is homed to an EdgeRTR it is able to communicate with H3Servers to leverage and support the mobility network. 5. Mobility Clients-Network-Servers The mobility network functions as a standard LISP VPN overlay. The overlay delivers unicast and multicast packets across: - multiple access-network providers / radio-access technologies. - multiple cloud-edge hosting providers, public, private, or hybrid. We use data-plane XTRs in the stack of each mobility client and server. ClientXTRs and ServerXTRs are homed to one or more EdgeRTRs at the LISP edge. This structure allows for MobilityClients to "show-up" at any time, behind any network-provider in a given mobility network administrative domain (metro), and for any H3Server to be instantiated, moved, or failed-over to any rack in any cloud-provider. The LISP overlay enables these roaming mobility network elements to communicate un-interrupted. This quality is insured by the LISP RFCs. The determinism of identities for MobilityClients to always refer to the correct H3Servers is insured by H3 geospatial HIDs. LISP location-identity-separation makes HIDs network addressable elements. There are two options for how we associate ClientXTRs with LISP EdgeRTRs: I. semi-random through DNS based load-balancing In this option we assume that in a given metro edge a pool of EdgeRTRs can distribute the Mobility Clients load randomly between them and that EdgeRTRs are topologically more or less equivalent. Each RTR uses LISP to mesh with the other RTRs in order to connect each Mobility Client with H3 Servers. Mobility Clients can (multi) home to the same RTR(s) throughout a ride. II. geo-spatial, where a well known any-cast RTR aggregates H3.r9 hexagons In this option we align an EdgeRTR with a geo-spatial cell area, very much like in Evolved Packet Core (EPC) solution. Mobility Clients currently roaming in an area home to that RTR and so is the H3 Server. There is only one hop across the edge overlay between clients and servers and mcast replication is more focused, but clients need to keep re-homing as they move. To summarize the H3LISP mobility network layout: (1) Mobility-Clients traffic is tunneled via data-plane ClientXTRs ClientXTRs are (multi) homed to EdgeRTR(s) (2) H3Server traffic is tunneled via data-plane ServerXTR ServerXTRs are (multi) homed to EdgeRTR(s) (3) EdgeRTRs use mapping service to resolve Ucast HIDs to RTR RLOCs EdgeRTRs also register to (Source, Group) H3Server HID multicasts MobilityClients <> ClientXTR EdgeRTR v v v << Map-Assisted Mobility-Network Overlay << v v >> EdgeRTR ServerXTR <> H3Servers 6. Mobility Unicast and Multicast Which ever way a ClientXTR is homed to an Edge RTR, via DNS metro load-balance or via a well known geo-spatial map of IPs (a few 10Ks per large metro area), an authenticated MobilityClient EID can send: [64bitH3.15ID :: 64bitState] annotation to the H3.r9 HID server. The H3.r9 IP HID can be calculated by clients algorithmically form the H3.15 localized snapped-to-tile annotation. The ClientXTR encapsulates MobilityClient EID and the H3Server HID in a packet sourced from the ClientXTR, destined to the EdgeRTR RLOC IP, Lisp port. EdgeRTRs then re-encapsulate annotation packets either to remote EdgeRTR (optionI) or to homed H3Server ServerXTR (option2). The remote EdgeRTR aggregating H3Servers re-encapsulates MobilityClient EID, H3Server HID to the ServerXTR and from there to the H3Server. To Summarize Unicast: (1) Mobility Clients can send annotation state localized an H3.r15 tile These annotations are sent to an H3.r9 mobility server (2) Source Client EID and Dest HID are encapsulated XTR <> RTR <> RTR <> XTR * RTRs can map-resolve re-tunnel HIDs to remote RTR RLOC (3) RTRs re-encapsulate original source-dest to ServerXTRs ServerXTRs decapsulate packet and serve the original packet to H3Server Each H3.r9 Server is used by clients to update H3.r15 tile state is also an IP Multicast channel Source used to update subscribers on the aggregate state of the H3.r15 tiles in the H3.r9 Server. We use rfc8378 signal free multicast to implement mcast channels in the overlay. The mobility network has many channels and relatively few subscribers per each. MobilityClients driving through or subscribing to a a H3.r9 area can explicitly issue an rfc4604 MLDv2 in-order to subscribe, or, may be subscribed implicitly by the EdgeRTR gleaning to ucast HID dest. The advantage of explicit client MLDv2 registration trigger to rfc8378 is that the clients manage their own mobility mcast hand-over according to their location-direction moment vectors, and that it allows for otherwise silent, or, non annotating clients. The advantage of EdegRTR implicit registration is less signaling required. MLDv2 signaling messages are encapsulated between the ClientXTR and the LISP EdgeRTR, therefore there is no requirement for the underlying network to support native multicast. If native access multicast is supported (for example native 5G multicast), then MobilityClient registration to H3Server road-safety channels may be integrated to it, in which case the evolved-packet-core (EPC) element supporting it (eNB) will use this standard to register with the appropriate H3.r9 channels in its area. EdgeRTRs note the subscribed MobilityClient stack XTRs and register as channel subscribers in the mapping system (Source, Group) entry. This is done at the first subscription request, if additional MobilityClients homed to the same EdgeRTR register for the same channels the EdgeRTR registration covers them. Upon receiving a multicast packet the EdgeRTR homing H3.r9 Servers resolve the (S,G) remote EdgeRTRs registered for the channel and replicates the packet. ` The remote EdgeRTRs homing MobilityClients in-turn replicate the packet to the MobilityClients registered with them. We expect an average of 600 H3.r15 tiles of the full 7^6 (~100K) possible in H3.r9 to be part of any road. The H3.r9 server can transmit the status of all 600 or just those with meaningful state based on update SLA and policy. To Summarize: (1) H3LISP Clients tune to H3.r9 mobility updates using rfc8378 H3LISP Client issue MLDv2 registration to H3.r9 HIDs ClientXTRs encapsulate MLDv2 to EdgeRTRs who register (s,g) (2) ServerXTRs encapsulate updates to EdgeRTRs who map-resolve (s,g) RLOCs EdgeRTRs replicate mobility update and tunnel to registered EdgeRTRs Remote EdgeRTRs replicate updates to registered ClientXTRs 7. Security Considerations The way to provide a security association between the ITRs and the Map-Servers must be evaluated according to the size of the deployment. For small deployments, it is possible to have a shared key (or set of keys) between the ITRs and the Map-Servers. For larger and Internet-scale deployments, scalability is a concern and further study is needed. 8. Acknowledgments This work is partly funded by the ANR LISP-Lab project #ANR- 13-INFR-009 (https://lisplab.lip6.fr). 9. IANA Considerations I. Formal H3 to IPv6 EID mapping II. State enum fields of H3 tiles: Field 0x describes the "freshness" of the state { 0x: less than 1Sec 1x: less than 10Sec 2x: less than 20Sec 3x: less than 40Sec 4x: less than 1min 5x: less than 2min 6x: less than 5min 7x: less than 15min 8x: less than 30min 9x: less than 1hour Ax: less than 2hours Bx: less than 8hours Cx: less than 24hours Dx: less than 1week Ex: less than 1month Fx: more than 1month } field 1x: persistent weather or structural { 0x - null 1x - pothole 2x - speed-bump 3x - icy 4x - flooded 5x - snow-cover 6x - snow-deep 7x - construction cone 8x - curve } field 2x: transient or moving obstruction { 0x - null 1x - pedestrian 2x - bike 3x - stopped car / truck 4x - moving car / truck 5x - first responder vehicle 6x - sudden slowdown 7x - oversized-vehicle } field 3x: traffic-light timer countdown { 0x - green now 1x - 1 seconds to green 2x - 2 seconds to green 3x - 3 seconds to green 4x - 4 seconds to green 5x - 5 seconds to green 6x - 6 seconds to green 7x - 7 seconds to green 8x - 8 seconds to green 9x - 9 seconds to green Ax - 10 seconds or less Bx - 20 seconds or less Cx - 30 seconds or less Dx - 40 seconds or less Ex - 50 seconds or less Fx - minute or more left } field 4x: impacted tile from neighboring { 0x - not impacted 1x - light yellow 2x - yellow 3x - light orange 4x - orange 5x - light red 6x - red 7x - light blue 8x - blue } field 5x: incidents { 0x - clear 1x - light collision (fender bender) 2x - hard collision 3x - collision with casualty 4x - recent collision residues 5x - hard brake 6x - sharp cornering } field 6x - compiled tile safety rating { } field 7x: LaneRightsSigns { 0x - stop 1x - yield 2x - speedLimit 3x - straightOnly 4x - noStraight 5x - rightOnly 6x - noRight 7x - leftOnly 8x - noLeft 9x - noUTurn 10x - noLeftU 11x - bikeLane 12x - HOVLane } field 8x: MovementSigns { 0x - noPass 1x - keepRight 2x - keepLeft 3x - stayInLane 4x - doNotEnter 5x - noTrucks 6x - noBikes 7x - noPeds 8x - oneWay 9x - parking 10x - noParking 11x - noStandaing 12x - loadingZone 13x - truckRoute 14x - railCross 15x - School } field 9x: CurvesIntersectSigns { 0x - turnsLeft 1x - turnsRight 2x - curvesLeft 3x - curvesRight 4x - reversesLeft 5x - reversesRight 6x - windingRoad 7x - hairPin 8x - 270Turn 9x - pretzelTurn 10x - crossRoads 11x - crossT 12x - crossY 13x - circle 14x - laneEnds 15x - roadNarrows } field Ax - reserved field Bx - reserved field Cx - reserved field Dx - reserved field Ex - reserved field Fx - reserved 10. Normative References [I-D.ietf-lisp-rfc6833bis] Fuller, V., Farinacci, D., and A. Cabellos-Aparicio, "Locator/ID Separation Protocol (LISP) Control-Plane", draft-ietf-lisp-rfc6833bis-07 (work in progress), December 2017. [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, . [RFC6830] Farinacci, D., Fuller, V., Meyer, D., and D. Lewis, "The Locator/ID Separation Protocol (LISP)", RFC 6830, DOI 10.17487/RFC6830, January 2013, . [RFC8378] Farinacci, D., Moreno, V., "Signal-Free Locator/ID Separation Protocol (LISP) Multicast", RFC8378, DOI 10.17487/RFC8378, May 2018, . Authors' Addresses Sharon Barkai Nexar CA USA Email: sharon.barkai@getnexar.com Bruno Fernandez-Ruiz Nexar London UK Email: b@getnexar.com Ohad Serfaty Nexar Israel Email: sharon@fermicloud.io Alberto Rodriguez-Natal Cisco Systems 170 Tasman Drive San Jose, CA USA Email: natal@cisco.com Fabio Maino Cisco Systems 170 Tasman Drive San Jose, CA USA Email: fmaino@cisco.com Albert Cabellos-Aparicio Technical University of Catalonia Barcelona Spain Email: acabello@ac.upc.edu Jordi Paillissé-Vilanova Technical University of Catalonia Barcelona Spain Email: jordip@ac.upc.edu Dino Farinacci lispers.net San Jose, CA USA Email: farinacci@gmail.com