Hi Rajiv, One of the issues is that many early deployments of smart meter are using IEEE 802.15.4. That technology uses extremely small packet sizes (127 byte packets).
Meanwhile, each of the device manufacturers using smart meter information are choosing their own link layer technology. SAE (electric cars) are looking to deploy powerline carrier (HomePlug GreenPHY seems to be the leading candidate, IEEE P1901 subset). So for simple smart meter deployments, the router won't necessarily be present. However, as devices like plug in electric vehicles are deployed and connected to the smart meter, you will end up with routers as well as the CPE router device. Don On 8/3/11 9:46 AM, "Rajiv Asati (rajiva)" <[email protected]> wrote: >Don, > >Just curious about 'smart energy' home network - Why is there a router >behind the CPE router? > >Cheers, >Rajiv > > >> -----Original Message----- >> From: [email protected] [mailto:[email protected]] On Behalf >Of Don >> Sturek >> Sent: Wednesday, August 03, 2011 10:25 AM >> To: Torbet, Dan; [email protected]; [email protected] >> Subject: Re: [v6ops] default LAN routing protocol for IPv6 CE router >> >> Hi Dan, >> >> Here is the initial scenario we are dealing with in the smart energy >arena: >> >> >> >> Provider (eg ISP) Provider (eg >utility) >> | >> | >> CPE router >> CPE router >> | >> | >> Router --------------------------------- >router >> | Link layer >> | >> | Interconnect >> | >> <Macs, >> <Smart appliances, >> iPads, >> plug in vehicles, >> Entertainment....> >load >> shed devices....> >> >> I purposely drew in the devices the way I did since some of these >networks >> will evolve as silos then will interconnect when customers upgrade >their >> routers to ones with multiple link layers that accommodate >interconnection. >> >> Ultimately, there will not be such a rigid division of devices like >shown but >> wanted to emphasize the likelihood that there will be multiple CPE >routers in >> the home and an interconnection between them within the home. >> >> Don >> >> >> >> >> From: "Torbet, Dan" <[email protected]> >> Date: Wed, 3 Aug 2011 07:42:53 -0600 >> To: "[email protected]" <[email protected]>, "[email protected]" ><[email protected]> >> Subject: [v6ops] default LAN routing protocol for IPv6 CE router >> >> >> >> The conversations so far on this topic have been great. I think >however, we >> need to take a step back for a moment and think through what the >HOMENET >> network looks like when serviced by a CPE Router. In my mind, we have >a few >> scenarios that are possible. >> >> >> >> >> The first is a CPE ingress router to the home and no other routers. >There may >> be in this device multiple SSIDs and they each might need to have >their own >> address space and have separate firewall/filtering rules. In this >case, >> everything is contained in a single box and so no additional routing >protocols >> are needed. This has been defined in the CPE router (RFC 6204) and >the bis >> extension that is in draft right now. >> >> >> >> The second case is a CPE ingress router with N routers behind it. In >this >> case, I humbly submit that anything where N is greater than 2 says >medium >> sized business maybe larger. I find it real hard to get any deeper >than 2 >> routers in series for a HOMENET class device deployment. Anything >greater than >> that and you likely would not use this class of device anyway. Sure >there >> will be situations where this is not true ,but I'll wager that in 90% >of the >> installations where a CPE router is providing the link to the world, >this will >> be the case. Even factoring in SmartGrid I just can't see a very deep >> network. Is there a use case for more than 1 or 2 layers in a HOMENET >> deployment that uses a CPE router as the connection to the world? To >be clear >> here - this is what I mean: >> >> (sorry for the poor ASCII art here ) >> >> >> >> Provider Router -------- CPE router ----------Router >------ >> Router >> >> >> >> Or >> >> >> >> >> >> Provider >> >> | >> >> CPE Router >> >> ^ >> >> Router >Router >> >> | >> | >> >> Router >Router >> >> >> >> I will acknowledge that in some business cases you might place a >router on >> each floor or each building in a campus, but this is where things get >blurry >> for me - would you really use a CPE router in these cases for ingress >into the >> business? You certainly could, but would you? >> >> >> >> Given that, I think that defining how many routers exist behind this >CPE >> ingress router will provide us with a reasonable place from which to >define >> the needs and requirements for an IGP running in the home. >> >> >> >> Dan >> >> _______________________________________________ v6ops mailing list >> [email protected] https://www.ietf.org/mailman/listinfo/v6ops _______________________________________________ homenet mailing list [email protected] https://www.ietf.org/mailman/listinfo/homenet
