Pymesh updates

  • Hi community 🙌

    I want to share with you the Pymesh (LoRa Mesh) current development and plans; last release of Pymesh is in v1.20.0.rc7
    For starting, this is my Pymesh presentation(workshop) done at TTN Conf Jan 2019 Amsterdam; if you have any questions 🗣
    As I've said in a previous mail, currently I'm working on the Border Router feature, I try to explain in a nice micropy script, basically how Pymesh data can be exposed outside of mesh, on Wifi/BLE/Cellular to the ☁.
    Not to forget the 📕 were copied here: and with a disclaimer, as Pymesh is included just in RC (development) releases.
    But, no worries, 😅 we'll include it in the first official stable.
    We're planning in releasing firmware releases with and without Pymesh, due to relatively large (~200KB) code-size.
    I'm working at the road-plan for further Pymesh features.
    Long-term plan is exposing more openthread features, make tons of tests (lots of nodes, distance); connect Pymesh with Pybytes, optimise power-consumption, security for private Pymesh, profile some KPI (data able to be sent over Pymesh), and of course share all plans with community (basically I will open-source the micropy scripts presented in workshop, have some articles to explain all use-cases).
    Just let me know your thoughts, about the further projects, and we could include requirements into official development.

  • Hi community,

    I've released a beta version of the Pymesh mobile app:

    In this repo there are firmware binaries (but latest development should work too), and micropy scripts (but should be also fine).

  • @rfinkers yes, it should work fine with L01, due to increased RAM+Flash.

  • @catalin said in Pymesh updates:

    It was tested on a 20+ Mesh network on Lopy4 and Fipy (sorry Lopy1 can't work with these scripts, due to scripts size and RAM requirements).

    Does it work on the L01? It has the same amount of RAM and flash as the Lopy4.

  • Just a small note, the v1.20.0.rc8 for Fipy and Pybytes scripts doesn't have Mesh class inside LoRa (so no Pymesh feature included).
    Due to an error, Pymesh was excluded on Lopy4 rc8 builds, too; this is about to be fixed as I speak.

  • Hi community 🙌,
    I've been busy lately making Pymesh application protocol more robust ⚙.
    I've just released a relatively large 🐘 micropy project using Pymesh:
    It was tested on a 20+ Mesh network on Lopy4 and Fipy (sorry Lopy1 can't work with these scripts, due to scripts size and RAM requirements).
    I am really waiting for your comments and PRs, I foresee tons of improvements 🤓.

    Heads-up, I am working on a visual tool, like a Pymesh viewer to actually click buttons and follow Pymesh evolution. Most probably connecting Pymesh to Pybytes 🌥.

  • @catalin SF is 7, Bandwidth is 125. The RssI values were not being printed.

  • @jordan-reyes I did not properly tested Pymesh on Lopy1, mainly because the scripts that I use, occupy lots of RAM.
    What LoRa params are you using, spreading-factor, bandwidth? I would start tests with fastest datarate (SF7, BW 250). Are you printing the RSSI values, if they are at the border (for that SF, for ex: lower than -115), there could be corrupted packets, that Node could exit/re-enter the Mesh.
    10 seconds is a small waiting time; Mesh internally sends, every 32 seconds, sends a keepalive between each pair of neighbours (last communication is in the age field from Mesh.neighbors() and Mesh.routers()).

  • @catalin deployed rc8 upon boot up nodes hit (outside With Line of sight ) and they are suppose to respond every ten seconds, some responsive more than others but after some time they do not send data anymore. Sometimes it lasts an hour sometimes a day but it is not reliable. What is environment you are running your set upon. We are covering about 2.25-2.5 km.

  • @catalin with both deployed is orignial lopy, not lopy4 would this be any difference with about 12 nodes. it was running for a bit and then would crash, but we weren't getting stable communication either, some were more consistent then others.

  • Hi Jordan,
    Yes, please try the RC8 release, I did not had any issue with RC7, either.
    Now I am running the Pymesh with ~30 micropython scripts (sending data to the Cloud, using Wifi and BLE), also creating Pymesh with 20+ nodes(lopy4 and Fipy), no Error found.

  • @catalin had a lot of issues with 1.20.0.rc7 almost all nodes were corrupted with guru meditation error on lora.mesh. the mesh seemed to be the issue, The error did not seem to be on previous versions, (although it wasn't run very long on previous version prior to update), I am hoping with rc8 this problem is fixed....

  • @catalin ooo, interesting. Thanks for the update.


  • Hello everyone,

    In the release 1.20.0.rc8 the Pymesh was updated, please check

    As usual, let me know what's not clear, the Border Router example a bit too simple.

  • Hi @jordan-reyes, announcing a stable release with Pymesh included, it's not a matter of Pymesh being not stable. There are some other features/improvements that need to be tested in whole firmware. Sorry, I don't know more details, probably the bugs/requests were raised on forum :)

    Some new Pymesh features were just released internally (so they will be incorporated in the next RC, probably this Friday) plus some example scripting for Border Router:

    • added socket binding to IP, add listing border_router
    • BUG: src and dest port on BR should he Host Swapped
    • Mesh.rx_cb() added argument, with the callback
    • added Mesh.border_router_del(prefix) method, for erasing Border Router entry
    • added multi-socckets (max 3)
    • added Border Router socket with header IP and port destination
      I did not forgot, we'll open-source some Pygo example scripts, as promised. I need to update/test for the new release.

    Plus, working on some Pymesh Roadmap...

  • @catalin Awesome when do you think stable version to be released?

  • For the Networks Engineers 🤓, this are the OSI Layers that are stacked into LoRa Mesh (Pymesh) feature:
    0_1551267465638_Screenshot 2019-02-27 at 13.36.32.png
    So, @thinginnovations Andrew, the IPv6 routing is already handled at Transport level.

  • hi Andrew,

    The router sends (routes) a packet to the destination, using the internal Thread routing(vector-distance algorithm). There could be some trouble, as the IPv6 of the destination should be known (either RLOC or ML-EID from here).
    In the TTN conf scripts I've implemented some sort or ARP (MAC to IP resolution), so node with LoRa MAC 0xA can send a message to the node 0xB, without knowing B's IPv6 (internally node A interrogates Leader to find IP of node B).
    I'll try to open-source them ASAP.

  • Thanks for the update.

    When a node designated as a router receives a packet is this automatically sent out to the neighbours or does the application code need to resend to neighbours in the receiver callback function?

    Thanks, trying to understand the process as I'm starting to build a larger mesh of nodes.



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