Network-Hexagons: H3-LISP Based Mobility Network
draft-barkai-lisp-nexagon-10

lt;---------------------------------------|                   |
          |               ACA (Interim)            |                   |

   Using this network-login / re-login method we ensure that:
   - the MobilityClientEIDs serve as credentials with the specific EdgeRTRs
   - EdgeRTRs are not tightly coupled to H3.r9 areas for privacy/load-balance
   - Mobility Clients do not need to update EdgeRTRs while roaming in a metro

   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 EdgeRTR it is able to communicate with H3ServiceEIDs.

5. Mobility Clients-Network-Services

  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, 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 H3ServiceEID 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 H3ServiceEID is insured by H3
  geospatial HIDs.

  There are two options for how we associate ClientXTRs with LISP EdgeRTRs:

  I. Semi-random load-balancing by DNS/AAA

  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 tunnel
  traffic to and from other EdgeRTRs for MobilityClient with H3Service exchanges.
  MobilityClients can (multi) home to EdgeRTRsRTRs throughout while moving.

  II. Topological by any-cast

  In this option we align an EdgeRTR with topological aggregation like in the
  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) H3ServiceEID 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) H3ServiceEID multicasts

       MobilityClients <> ClientXTR <Access Provider > EdgeRTR  v
                                                                v
       v      << Map-Assisted Mobility-Network Overlay <<       v
       v
       >> EdgeRTR <Cloud Provider> ServerXTR <> H3ServiceEID

6. Mobility Unicast and Multicast

  Which ever way a ClientXTR is homed to an Edge RTR an authenticated
  MobilityClient EID can send: [64bitH3.15ID :: 64bitState] annotation to the
  H3.r9 H3ServiceEID. 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 H3ServiceEID 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 H3ServiceEID ServerXTR (option2).
  The remote EdgeRTR aggregating H3ServiceEIDs re-encapsulates MobilityClient
  EID to ServerXTR and from there to the H3ServiceEID.

    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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ \
|Version| Traffic Class |           Flow Label                  |  |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+  |
|         Payload Length        |  Next Header  |   Hop Limit   |  |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+  |
|                                                               |  |
+                                                               +  |
|                                                               |  |
+                    Source MobilityClientEID                   +  |
|                                                               | IPv6
+                                                               +  |
|                                                               |  |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+  |
|                                                               |  |
+                                                               +  |
|                                                               |  |
+                       Dest H3ServiceEID                       +  |
|                                                               |  |
+                                                               +  |
|                                                               | /
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|       Source Port = xxxx      |       Dest Port = xxxx        | \
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ UDP
|           UDP Length          |        UDP Checksum           | /
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ \
|  Type         |gzip |        Reserved         | Pair Count = X| Nexgon Header
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ /
|                                                               |
+                       64 Bit H3-R15 ID                        +
|                                                               |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                                                               |
+                       64 Bit State                            +
|                                                               |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                                                               |
+                       64 Bit H3-R15 ID                        +
|                                                               |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                                                               |
+                       64 Bit State                            +
|                                                               |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

  To Summarize Unicast:

   (1) MobilityClients can send annotation state localized an H3.r15 tile
       These annotations are sent to an H3.r9 mobility H3ServiceEIDs
   (2) MobilityClient EID and H3ServiceEID HID are encapsulated:
         XTR <> RTR <> RTR <> XTR
       * RTRs can map-resolve re-tunnel HIDs
   (3) RTRs re-encapsulate original source-dest to ServerXTRs
       ServerXTRs decapsulate packets to H3ServiceEID

  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 EdgeRTR 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 H3ServiceEID
  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.

  Multicast update packets are of the following structure:

    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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ \
|Version| Traffic Class |           Flow Label                  |  |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+  |
|         Payload Length        |  Next Header  |   Hop Limit   |  |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+  |
|                                                               |  |
+                                                               +  |
|                                                               |  |
+                       Source H3-R9 EID Address                +  |
|                                                               | IPv6
+                                                               +  |
|                                                               |  |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+  |
|                                                               |  |
+                                                               +  |
|                                                               |  |
+                          Group Address                        +  |
|                                                               |  |
+                                                               +  |
|                                                               | /
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|       Source Port = xxxx      |       Dest Port = xxxx        | \
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ UDP
|           UDP Length          |        UDP Checksum           | /
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ \
|                                                               | Nexagons Header
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ /
~                            Nexagons Payload                   ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Outer headers = 40 (IPv6) + 8 (UDP) + 8 (LISP) = 56
Inner headers = 40 (IPv6) + 8 (UDP) + 4 (Nexagon Header) = 52

1500 (MTU) - 56 - 52 = 1392 bytes of effective payload

Type 1:key-value, key-value.. 1392 / (8 + 8) = 87 pairs
Type 2:value, key,key,key.. (1392 - 8) / 8 = 173 H3-R15 IDs

 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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ \
|  Type =   1   |gzip |        Reserved         | Pair Count = X| Nexagon Header
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ /
|                                                               |
+                       64 Bit H3-R15 ID                        +
|                                                               |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                                                               |
+                       64 Bit State                            +
|                                                               |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                                                               |
+                       64 Bit H3-R15 ID                        +
|                                                               |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                                                               |
+                       64 Bit State                            +
|                                                               |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

 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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ \
|  Type =   2   |gzip |     Reserved            |H3R15 Count = X| Nexagon Header
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ /
|                                                               |
+                       64 Bit State                            +
|                                                               |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                                                               |
+                       64 Bit H3-R15 ID                        +
|                                                               |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                                                               |
+                       64 Bit H3-R15 ID                        +
|                                                               |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                                                               |
+                       64 Bit H3-R15 ID                        +
|                                                               |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

` 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 nexagon layer3 v2v/v2i/c&c network is inherently more secure and private
  then alternatives because of the indirection. No car or infrastructure element
  ever communicates directly with MobilityClients. All information is conveyed
  using shared / addressable geo-state. MobilityClients are supposed to receive
  information only from the network as a trusted broker without indication as
  to the origin of the information. This is an important step towards better
  privacy, security, extendability, and interoperability.

  In order to be able to use the nexagon mobility network for a given period,
  the mobility clients go through a DNS/AAA stage by which they obtain their
  clientEID identifiers-credentials and the RLOCs of EdgeRTRs they may use as
  gateways to the network. This MobilityClient <> EdgeRTR is the most sensitive
  interface in the network as far as privacy-security.

  The traffic on the MobilityClient<>EdgeRTR interface is tunneled  and its UDP
  content may be encrypted, still, the EdgeRTR will know based on the LISP
  headers alone the MobilityClient RLOC and H3-R9 (~0.1sqkm) geo-spatial area
  a given client publishes in or subscribes to.

  For this reason we envision the ability of enterprise or groups of users to
  "bring their own" EdgeRTRs. BYO-RTR masks individual clients' IP-RLOC to
  H3-R9 association and is pre-provisioned to be able to use the mapping system
  and be on a white-list of EdgeRTRs aggregating H3ServiceEIDs.

  Beyond this sensitive hop, the mapping system does not hold MobilityClientEIDs
  and remote EdgeRTRs are only aware of MobilityClient ephemeral EIDs not their
  actual IP RLOC or any other mobile-device identifiers. EdgeRTRs register in the
  mapping (s,g) H3-R9 multicast groups, but which clients reside beyond which
  EdgeRTR is not in the mapping system. The H3ServiceEIDs them selves of-course
  decrypt and parse actual H3-R15 annotations, they also consider during this the
  MobilityClientEID credentials to avoid "fake-news", but again these are only
  temporary EIDs allocated to clients in-order to be able to use the mobility
  network and not for their basic communications.

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: Traffic Direction {
0x - null
1x - Lane North
2x - Lane North + 30
3x - Lane North + 60
4x - Lane North + 90
5x - Lane North + 120
6x - Lane North + 150
7x - Lane North + 180
8x - Lane North + 210
9x - Lane North + 240
Ax - Lane North + 270
Bx - Lane North + 300
Cx - Lane North + 330
Dx - junction
Ex - shoulder
Fx - sidewalk
}

field 1x: Persistent or Structural {
 0x - null
 1x - pothole light
 2x - pothole severe
 3x - speed-bump low
 4x - speed-bump high
 5x - icy
 6x - flooded
 7x - snow-cover
 8x - snow-deep
 9x - construction cone
 Ax - gravel
 Bx - choppy
 Cx - blind-curve
 Dx - steep-slope
 Ex - low-bridge
}

field 2x: Transient Condition {
 0x - null
 1x - pedestrian
 2x - bike scooter
 3x - stopped car / truck
 4x - moving car / truck
 5x - first responder vehicle
 6x - sudden slowdown
 7x - oversized over-height vehicle
 8x - red-light-breach
 9x - light collision (fender bender)
 Ax - hard collision / casualty
 Bx - collision course car/structure
 Cx - recent collision residues
 Dx - hard brake
 Ex - sharp cornering
 Fx - freeing-parking
}

field 3x: Traffic-light Cycle {
 0x - null
 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 - 60 seconds or less
 Ex - green now
 Fx - red now
}

field 4x: Impacted tile from neighboring {
 0x - null
 1x - epicenter
 2x - light yellow
 3x - yellow
 4x - light orange
 5x - orange
 6x - light red
 7x - red
 8x - light blue
 9x - blue
 Ax - green
 Bx - light green
}

field 5x: Transient, Cycle, Impacted, Valid for Next{
 0x - null
 1x - 1sec
 2x - 5sec
 3x - 10sec
 4x - 20sec
 5x - 40sec
 6x - 60sec
 7x - 2min
 8x - 3min
 9x - 4min
 Ax - 5min
 Bx - 10min
 Cx - 15min
 Dx - 30min
 Ex - 60min
 Fx - 24hours
}

field 6x: LaneRightsSigns {
 0x - null
 1x - yield
 2x - speedLimit
 3x - straightOnly
 4x - noStraight
 5x - rightOnly
 6x - noRight
 7x - rightStraight
 8x - leftOnly
 9x - leftStraight
 Ax - noLeft
 Bx - noUTurn
 Cx - noLeftU
 Dx - bikeLane
 Ex - HOVLane
 Fx - Stop
}

field 7x: MovementSigns {
0x - null
1x - keepRight
2x - keepLeft
3x - stayInLane
4x - doNotEnter
5x - noTrucks
6x - noBikes
7x - noPeds
8x - oneWay
9x - parking
Ax - noParking
Bx - noStandaing
Cx - noPassing
Dx - loadingZone
Ex - railCross
Fx - schoolZone
}

field 8x: CurvesIntersectSigns {
0x - null
1x - turnsLeft
1x - turnsRight
3x - curvesLeft
4x - curvesRight
5x - reversesLeft
6x - reversesRight
7x - windingRoad
8x - hairPin
9x - pretzelTurn
Ax - crossRoads
Bx - crossT
Cx - crossY
Dx - circle
Ex - laneEnds
Fx - roadNarrows
}

field 9x: Current Tile Speed {
0x - null
1x - < 5kmh
2x - < 10kmh
3x - < 15kmh
4x - < 20kmh
5x - < 30kmh
6x - < 40kmh
7x - < 50kmh
8x - < 60kmh
9x - < 80kmh
Ax - < 100kmh
Bx - < 120kmh
Cx - < 140kmh
Dx - < 160kmh
Ex - > 160kmh
Fx - queuedTraffic
}

field Ax - reserved
filed 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,
              <https://www.rfc-editor.org/info/rfc2119>.

   [RFC6830]  Farinacci, D., Fuller, V., Meyer, D., and D. Lewis, "The
              Locator/ID Separation Protocol (LISP)", RFC 6830,
              DOI 10.17487/RFC6830, January 2013,
              <https://www.rfc-editor.org/info/rfc6830>.

   [RFC8378]  Farinacci, D., Moreno, V., "Signal-Free Locator/ID Separation
              Protocol (LISP) Multicast", RFC8378,
              DOI 10.17487/RFC8378, May 2018,
              <https://www.rfc-editor.org/info/rfc8378>.

Authors' Addresses

   Sharon Barkai
   Nexar
   CA
   USA

   Email: sbarkai@gmail.com

   Bruno Fernandez-Ruiz
   Nexar
   London
   UK

   Email: b@getnexar.com

   S ZionB
   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