Hi Jim, I fully agree with you. Declaring OLSRv2 etc. out of scope just because "a home is not a mesh network" seems simplistic to me. As you explained in your mail, many of the problems that mesh networks already solve successfully today, can be very similar in a home: dynamic topology, no skilled network operator centrally managing the devices, wireless and wired devices, limited resources on the routers etc. These were exactly the motivation for developing such protocols in MANET.
Best regards Ulrich On 10/12/11 3:10 AM, Jim Gettys wrote: > On 10/07/2011 03:48 AM, Fred Baker wrote: >> 4) The use of OLSR in mesh network scenarios >> >> Jim Gettys commented on the fact of OLSR use. The general sense of the room >> was that OLSRv2 is interesting but out of scope for this discussion as mesh >> networks are quite different from typical residential and SOHO networks. >> > Actually, I have no opinion of OLSR, Babel, Babelz or OSPF; it's not my > area of expertise. > > Babel/BabelZ is appearing in CeroWrt today as the people who are > interested in such things are doing the work (we don't need a routing > protocol in the simple single home router case), and it provided the > functionality we needed. > > For those who want something else, quagga is in the CeroWrt build for > your hacking pleasure. > > And I'm not advocating the homenet working group do anything unusual > about routing at this date; as I said, it's not my area of expertise. > > Having said this, I do note the following technological trends: > > 1) As soon as we get real "plug and play" routers that don't need manual > configuration that work, we'll see a lot more routers in a home > environment. Other radio technologies (e.g. zigbee) may encourage this > trend. It seemed like the working group agreed that getting to the > point that just hooking things together would really "just worked" was a > fundamental requirement (and I agree entirely with this sentiment, as it > reflects reality of what already happens in the homes of hackers and > non-hackers alike). > > 2) wireless is much cheaper to implement than wired networking, > particularly in most houses where pulling cable is hard. I know this > first hand, where I've pulled a lot of cat 6 and wish I could get it to > places I don't have it. > > Unless power line networking really works, I believe that this trend > isn't going to change. Is there any progress in this area? I've seen > many promises, and few reliable working products. > > 3) As soon as you have two routers, you have at least two paths; the > wired connection between them and the wireless. You may have 3 paths, > if you have both 2.4 and 5ghz radios. Frequency diversity routing > becomes immediately interesting, along with using your ethernet when > it's available in preference to wireless. > > 4) an apartment building look like a mesh, and possibly with multiple > backhauls possibly with multiple ISP's. One should at least think about > what happens when you have "homes", in such a building, and make sure > nothing breaks. Wireless is messy: it isn't limited to where a wire > goes. Taking down an entire apartment building/blocks/city would not be > fun. I know, I've been there (at least to the point of taking down > buildings, and came within a week of a much larger scale disaster). > > If you believe 1 + 2 + 3 +4 (as I do), then if you look a few years > out, you end up with something in the "home" that begins to resemble > very strongly what the community mesh networking folks are doing at a > higher scale geographically and in terms of # of nodes today, with > many/most of the same concerns and solutions. Understanding the problems > they've faced/are facing is therefore worth a bit of investment; Radio > diversity is one of the concerns, and interference (of various sorts). > > Julius' talk about why frequency diversity is an issue is here: > > http://www.youtube.com/watch?v=1VNzm0shSA8 > > While the issues outlined above are not where home networking is today, > my gut feel is they will be in five years. > > If there is *anything* I can urge on the group, is to respect the > scaling problems that can/will occur, and to internalise wireless > !=wired: wireless goes where wireless goes and does not behave like > ethernet. The group needs to ensure nothing "bad" happens when people > start building systems in ways you don't expect, particularly in an > apartment building. The challenge is balancing the reality of how > wireless works, with "just works" automatic configuration, with "fail > safe" behaviour. > - Jim > > > > > > > > _______________________________________________ > homenet mailing list > homenet@ietf.org > https://www.ietf.org/mailman/listinfo/homenet _______________________________________________ homenet mailing list homenet@ietf.org https://www.ietf.org/mailman/listinfo/homenet
