March 2013 - PSDR - mailman.hamwan.org

Re: [HamWAN PSDR] Mesh backbone
by Bart Kus 13 Mar '13

13 Mar '13

Hi Craig, First, let's speak the same language. There's a lot of confusion around the word "MESH". I'm also not sure why it's always capitalized. It's not an acronym as far as I know. The term "mesh network" describes nothing more than the logical topology of a network. There's a really good write-up on this at the wikipedia page <http://en.wikipedia.org/wiki/Mesh_networking>. I'm pretty sure that when you (and others on this email) use the phrase "mesh network" it is not the wikipedia definition you're intending. It means something different, including: 1) Using a common RF channel 2) Promiscuous neighbor discovery + association 3) Automatic IP configuration based on MAC 4) Nearly open node authentication 5) Omnidirectional operation 6) WDS <http://en.wikipedia.org/wiki/Wireless_distribution_system>-style operation These are the typical traits of a SeattleWireless <http://seattlewireless.net/> style mesh network (which, BTW, has been attempting to bootstrap itself for the last 13 years). This type of definition of "mesh network" is quite a different animal from the canonical mesh network definition (wikipedia's, derived from network theory). The reason I want to make the distinction clear is that nearly all large networks in the world are indeed mesh networks, but nearly none of them possess the qualities of 1-6. So when I say something like "HamWAN <https://www.hamwan.org/t/tiki-index.php> is a mesh network", I want it to be clear that I'm referring to the network topology only (the wikipedia definition). I'm not sure what is the right word to describe the other type of network; perhaps capitalizing all the letters is a good differentiator after all. :) So, with the definitions out of the way, let me address your actual email now that I can speak to it unambiguously. I concur that we all want to implement a mesh network, but I don't think everyone wants to implement a MESH network. Phrasing the problem of "how do we provide modern digital communications to the ham community" in terms of "how do we implement a MESH network" is putting the cart before the horse. Over the last 6 months, I've been leading the HamWAN effort to create solutions to the first question. We've made respectable progress on both the RF engineering and networking fronts. We had a fully functional cell site setup @ last weekend's Flea Market. This site design is about to start rolling out to the real world. This transition in the project's status has allowed me to start thinking about how HamWAN might integrate with other ham networking efforts. We've had a good relationship with BCWARN.net <http://www.bcwarn.net/intermapper/rf-map.html> for the last few months, and integration with that network will be simple. The physical links are already planned in fact! We're both excited to make it happen and start exchanging traffic internationally! The integration with NW-MESH efforts is far more challenging. In fact, it may be outright impossible unless changes are made in the NW-MESH design. From what I've seen, this difficulty of peering will be present in all MESH networks. The problems range from simple route exchange, to address space conflicts, to policy propagation (access, QoS, filtering, etc). I don't even wanna think about DNS. :P Having said all that, there is some value to HamWAN using a MeSh (hybrid of mesh and MESH) layer. Traffic between nodes may flow more optimally on the ground than through the mountain sites. A nearby ham who doesn't want to invest in a dish might get on HamWAN by MeShing with his neighbor. I'd be good for the health of HamWAN to make use of these optimizations. But like I said, in order for these routing decision to be made correctly and automatically, NW-MESH designs will need to change. I'd like to invite you (in fact, all of you) to join the HamWAN weekly meeting today @ 7PM. I'll re-send the connectivity details on the mailing list (email: psdr-join(a)hamwan.org) an hour before the meeting, but basically install Mumble <http://mumble.sourceforge.net/> 1.2.4 <http://mumble.info/snapshot/mumble-1.2.4-rc1-8-gb115a29.msi>+ (currently beta), and connect to BartK.us. Please use a headset to avoid generating echoes. Craig, can you give me an idea of your skills? Perhaps you would enjoy solving these types of problems as part of the HamWAN development team? We run a tight ship with specific assignments and weekly reporting. I believe this is the "small group of experts" approach you were proposing. :) --Bart On 03/12/2013 12:09 PM, Craig B wrote: > When I first heard about the MESH project from Daniel Stevens (KL7WM) > back in late fall 2012, the first question I had for him was "what > will it connect to?" Since then, as I have become more involved I > have started to formulate what I think it could be connected to and > how it could be used. > > Based on what I have learned and seen to date, I see 3 tiers of > network involved here. The backbone, which I see as a long-haul that > would be based on a region that is defined by terrain and distance. > The middle tier would be smaller and could be between HAM towers or > other "secondary" sites. The 3rd tier would be for the "neighborhood" > or "home" MESHing with WRT's and other low-power devices. In this > type of configuration, I see the backbone as being the one common > piece across regions while the secondary and tertiary tiers could be > specific to the 'regional' implementation. Each tier would have to > bridge from itself to the next level, which seems to be reasonable > where a given site could choose to bridge by adding necessary hardware > or remain remote. > > What I would like to do is see if we can't get a written network plan > for a regional backbone and then any additional tiers that need to be > included in a good network design document. I am a firm believer that > it should be hardware agnostic for the most part, although could > provide a list of acceptable components that have been shown or > believe to be the best hardware based on application. It would also > dictate how traffic might be handled moving up/down through the tiers, > possibly allowing for QoS or other transport methods. > > As I am sure we all want to see a MESH network available to all HAMs; > given the area NW-MESH has been getting feedback on, I think we need > to start looking at how we connect them all together. As such, in > talking with Bob Rutherford, it seems like the first step is to build > out a plan that could be presented to FWARC, Tukwila Radio Club, and > EMCOMM (and other clubs/groups). > > Since this is all great in theory, it seems the next step is to secure > funding and move it from paper to reality. Given the real application > of this MESH network for EMCOMM, and their generally deep pockets, it > seems like a great way to get a backbone built. > > If we are going to design this, I believe it needs to be initially > designed by a small group of network and radio experts. Once an > initial plan is cobbled together it could be released to the larger > MESH community for comments and additions/subtractions, etc. > > I am willing to take on leading this charge; however, I will need a > team of experts behind me helping lay the ground work. My initial > thought is to have something ready by mid or late summer, given that > we all have other priorities as well, not adverse to taking longer if > it means having a complete and well planned out design. > > Any thoughts on this? > > Thanks, > Craig > KF7LLA

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Meeting notes March 5th, 2013
by Bart Kus 12 Mar '13

12 Mar '13

1) Ben published draft bylaws. We'll review/tweak this week, and then submit for voting. He's continuing to investigate insurance policy. I need to forward MicroHams policy info to him. Ben will help with setup on Friday by way of truck. Ben's also putting together the server/switch side of the Flea Market demo. Setting up asterisk as one service. 2) Curt got us a 50 minute presentation @ SeaPac!!! Details forthcoming. He'll forward background image to Ben for banner creation, and will submit own design if possible. Curt will engage with Seattle ACS folks to see how HamWAN can help their emergency activities. BANNER DESIGN MUST BE SUBMITTED TOMORROW 3) Cory's back and working on 802.1x/authentication. Was off the last 2 weeks. Will supply SIP phone for Flea Market. 4) Rob couldn't attend but here's his update: Greetings all, I will be unable to make >this< meeting tomorrow, due to >another< meeting. Perhaps we should have a meeting about scheduling meetings? (no, just kidding) 1)Rotor control software progress -- moderate, but not nearly fast enough. Availability of time is the issue. 1^st run in VB is probably 75% along. Got the cable back from Scott so I can test. Need to pick someone's brain on the interface to the test equipment. Do I simply poll for whatever value is presented (i.e. the TE is continuously sending output), or do I need to send a command parameter then get a response, etc, etc. 6)It looks like I will be going to Puyallup after all. Previous commitment has been cancelled. Not sure how much time I'll have between now and then, but what needs to be done? (I'm really going to hate myself for asking that...) I cannot be there late as we do have other commitments that evening around 6 up north. Rob 5) KD7ILD will contact Housing Authority about hosting sites. Focus on Beacon Tower. Other site development in progress as well. 6) I'll setup the cell site here and generate OpenVPN creds for people to dial in and make sure everything is working prior to the Flea Market. General discussion points: 1) We'll go with the full blown RF analysis display @ Flea Market. Heavy, but nifty. There will be enough people to cover the table so things don't get messed with. 2) New member "megor" has promised to get his ham license this Saturday. Go Team Megors! 3) Banner printing will have to be local / quick. FedEx is looking likely. I'll check their rates. 4) We postponed the discussion on the FCC's Notice of Proposed Rulemaking. I need to draft a response and have the board sign it on behalf of HamWAN. Send it to state rep and ARRL and FCC? We'll figure that out. Many other finer points were omitted from this email.... --Bart

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Presentations
by Bill Vodall 08 Mar '13

08 Mar '13

> 2) Curt got us a 50 minute presentation @ SeaPac!!! Details forthcoming. > He'll forward background image to Ben for banner creation, and will submit > own design if possible. > BANNER DESIGN MUST BE SUBMITTED TOMORROW You're getting well prepared for these presentations.... Here's a techy local event asking for presentations that's sadly lacking any HAM radio presence... http://linuxfestnorthwest.org/ I've attended the last few of the Linux fests. It's not great but it's not bad and a good excuse to get out to do something different. There has been talk of a Xastir demo but nobody has had the time. 73 Bill - WA7NWP

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FCC Notice of Proposed Rule Making (NPRM) 13-22
by Bart Kus 05 Mar '13

05 Mar '13

Attaching an FCC notice which affects HamWAN and all ham users of the 5GHz band. Have a read. So long. --Bart

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Agenda for tomorrow's meeting (March 5th, 2013)
by Bart Kus 05 Mar '13

05 Mar '13

Hello, 1) Rob will update us on rotor control software progress. 2) Ben will update us about insurance policy details, and will present bylaws document. 3) Curt will update us on the Banner front for the Flea Market, and on future bookings, especially SeaPac. 4) Cory will update us on 802.1x/authentication research work. 5) We will discuss and settle on the Flea Market plan of action. Times when we'll meet to take specific hardware to deploy on Friday evening. Who will attend @ the opening on Saturday and throughout the day. Who will be doing teardown and when. 6) Flea Market demo commitments. What scenarios are being realized and by who exactly? I've personally got to build the cell site (physically+network configs) and have to share it via OpenVPN with others building other parts of it. The central switch/router is not here yet to do this, so it might be challenging. 7) We need to respond to the FCC's intent to rule on further allocations in the 5GHz band. Their plan is to completely overlap the amateur radio allocation there with U-NII services. This puts us in a very bad spot spectrum-wise. 8) Site development work. DNR and others. Inviting KB7ILD and Mike Ping explicitly for this. If you'd like to append to this agenda, please respond to this email with your needs. New attendees welcome! You may walk away with work though. ;) *Meeting Details* *How* Mumble <http://mumble.sourceforge.net/> voice + text chat software (v1.2.4+, install the beta if needed) *Where* Connect to server "BartK.us" *When* Tuesdays @ 7:00PM PST for 1 hour *How* Please use a headset or enable Echo Cancellation --Bart

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Shields up, captain!
by Bart Kus 01 Mar '13

01 Mar '13

And despite all that, the attenuation between TX+RX antennas is still 65.5dB! This must be reflections internal to my garage. Gotta re-run these measurements outside. Also, the angles on the shield are too shallow. I gave it a 130 deg opening, but the back is recessed from the active elements of the antenna, so this doesn't actually shield as much as it should. It'll be fun to see this on the radiation pattern measurement range! See before + after. Might have to use a wider shield. This is 2ft by 1ft sheet. The bolt pattern won't work for production use. In real life, if these shields are to be used, they'll just hang on via the 2 mounting bolts at the very center of the back of the antenna. You can just see their nuts pointing up in the last picture. Undoing all the other bolts while the antenna is inside the radome would permanently break the antenna. Spacers would get knocked loose, and you'd have to destroy the radome to re-align things. This antenna is entirely metric. Horizontal spacing between all bolts = 6cm. Spacing between the upper/lower bolts and the inner bolts = 20cm. Spacing between the inner bolts = 6.8cm. Holes are fine with 1/4" drill. Bolts are M10. --Bart

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POLL: How do you feel about HamWAN network having shared control of the microwave modem @ your location?
by Bart Kus 28 Feb '13

28 Feb '13

Hello, Keeping the network and all client devices correctly configured is no easy feat. These are complicated devices with 100s of settings, which will need to change in coordinated ways over time. To ensure correct operation, it would make sense for the HamWAN network to push updates and change settings on end-user modems. Almost all ISPs run this way already. The difference is you can still login + control your device, but any setting changes you make which make the device non-compliant in ways HamWAN cares about would be automatically overridden with a config update from the network. If the network can't control and repair your device settings, you would lose authorization onto the network until the settings are fixed. I see this shared administration model as the only one that's feasible in keeping a reliable network running. Please let me know if you are OK with it, if you object to it, or if you have a better idea. Thanks, --Bart

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Clarification on client node routing (this means your home / EOC /etc)
by Bart Kus 28 Feb '13

28 Feb '13

There appears to be confusion about what client sites will look like. I have had the Client Node Routing <https://www.hamwan.org/t/tiki-index.php?page=Client+Node+Routing&structure=…> page up for a while, but it did not contain a clear pictographic view, nor a thorough textual description. I've now spent a little time to draw up a clear graphical representation of what to expect at your site. Just hit up that page to see. Your local router and wireless access point are staying, as is your Internet modem. The newly added HamWAN microwave modem + router will simply plug into the LAN side of your network. From a routing perspective, the HamWAN modem will announce routes to your main router via RIP /most likely/ (see below). These are subnets which are accessible via the microwave network and the packets for those subnets should be sent to the microwave modem. Default gateway /should/ (see below) stay as your main ISP. If you have received subnet routing services from HamWAN (ie: you have your own subnet which is announced into the rest of the HamWAN network) then you'll configure your LAN devices with your subnet's IPs. The open problems in this design are: 1) Asymmetric reply traffic when requests come into your HamWAN subnet from Internet IPs. The reply packets will attempt to leave via your ISP since it's your default gateway. We may have to do some policy routing on the main router to mitigate this, or multinet any network devices which want to talk out both networks. To be engineered. 2) DNS queries need to work for at least the HamWAN.net domain despite a total Internet failure (of both your local ISP and HamWAN's Internet links). DNS queries for regular Internet domains should be undisturbed during normal operation. HamWAN should not request any control over user routers beyond the HamWAN modem + router device. On the HamWAN modem + router device, users need to be free to define their own firewall rules and set other settings which do not conflict with HamWAN access policy. --Bart

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