Gigabit guarantee to local transit exchange

From home grid
Jump to: navigation, search

Many advocate fibre not just "to" but "into" the home, while few understand the implications of smart grid technologies once extended into the home. To address these misunderstandings, Craig Hubley suggests the terminology fibre to the home, fibre the curb [1] and even the homes with tails terminology "ought to be ditched in favour of fibre from transit exchange to transformer (for the hardware) and gigabit guaranteed to the meter" for services. In combination, a gigabit guarantee to local transit exchanges.

A smart home for instance could provide such a guarantee to every AC outlet, making smart appliances easy to support. Smart home.jpgGE Nucleus plug2 270x393 270x393.jpg

A transit exchange is a deliberately abstract concept (more so than "pole", "curb", "premises" or "meter") like "node", but implying open access to all service providers. Fibre neighbourhood pod.PNG Example: a fibre optic neighbourhood pod placed on a pole in Malaysia, unifying nearby homes with fibre optic "tails" into a public closet that many service providers can access. Swiss Telecom runs excess fiber where it wants to be free of onerous regulation.

Hubley cites five reasons for this shift of terminology:

between homes[edit]

"1. Fibre should normally not be deployed within the home - it's fragile, requires some expensive upgrades and could never (unlike the power-integrated copper networking of 802.3at/PoE and G.9960/EoP) reach every DC and AC device to maximize power conserving

2. Anyone who needs more than a gigabit is going to also want a redundant network to fail over to when there's a problem - thus a bona fide fibre-into-the-home application also requires hot copper backup. It would need it for power control anyway even without the data need.

Addressing 1 and 2:

To say "fibre from transit exchange to transformer" is specifying one of several possible ways to connect transit exchanges (or "neighbourhood closets") to the pole next to the house. It emphasizes that the transformer must be bridged around to get into the home with powerline technology and that it is where responsibility for maintenance may/should also change hands. It's deliberately agnostic on how one gets into the home once past the transformer - it could be one fibre continuing on past to a private home, could be G.9960 over cat3 or coax, or (best) G.9960/EoP on the existing AC power lines including a meter. Or all of these set up for failover.

Advocacy of linking the transit exchange to the transformer with fibre needs to be clearly separated from advocacy of fully integrated smart meters and home area networks (or "home grids"). They're two different issues, though both important to achieving the lowest long term footprint.

exchange to meter[edit]

Hubley further differentiates the issues from the exchange to the meter:

"3. Between transit exchange and the meter (entry point to the home, ignoring the transformer), what users really need is bandwidth and service level guarantees of low latency (say under 10ms) to the transit exchange, high (one gigabit) bandwidth and operation for some period of time even in a power outage (say 72 hours). Training users to demand these things, rather than "high speed" or "broadband" or "bandwidth enough to do VoIP" (no such thing, it's a latency concern not a bandwidth conern, G.729 runs on 7 kbps <-- notice the k w/ low latency).

4. The central role of the power meter in the optimal configuration is hard to over-emphasize. You need one anyway and this will be the authoritative device for any line loss, short or surge monitoring done by the powerco. If it's not fully integrated with the in-home devices then most of the benefits of integrated power and data disappear. Letting powercos put in non-IP or even just non-G.9960-compliant meters that can't participate in the home network is just another barrier to a genuine "smart grid" that can ask every AC outlet to perform a curtailment to level peaks, more dumb devices wasting power.

Addressing 3 and 4:

To say "gigabit guaranteed to the meter" is emphasizing the capacity G.9960 and 802.3at currently carry as a baseline, emphasizing it's a service guarantee not a type of hardware specified, and reinforcing the central role of the meter and responsibility of powercos to make it easy, not difficult, to smarten up homes.

Notice that the meter and the transformer are separated by the power mast and the service cable (which hangs between the pole and the mast, if you have a pole). Ownership of these devices varies somewhat in different regulatory regimes, but it's probably important for powercos to cede all control of data over the service cable and into the mast to whoever provides that gigabit guarantee. The motives for the powerco to roll out tariffed gigabit data service itself are: Enforce high authentication standards, not have to trust metering from third parties, control interface to emergency response agencies. However, if a responsible third party such as a local emergency management agency or insurance co-operative wants to take over both metering and service guarantees, that should not only be possible but facilitated by government. Powercos should not be in the position, for instance, of deciding which medically vulnerable persons should continue to get power to their medical devices in outages. Nor what other services should be considered essential."


He mentions the resilience issues as also requiring some grid advocacy terms to focus attention:

"Resilient buildings and communities will have to make such choices. We're best off thinking hard about them right now, not once we actually have smart devices out there and making life-critical decisions.

I don't have a catch phrase to describe the position optimal to advocate on this issue, but, we might think about "citizen control of life-critical service priority" rather than utility control. This should also replace the useless "net neutrality" slogan which seems to many people to justify giving P2P file sharing the same priority as VoIP calls for help from dying people or text messages from paramedics to the hospital. Rather than "neutrality" I suggest we need "sensitivity" to the real life implications of the traffic, rather than to the priorities of geeks or of the commercially-motivated utilities or govts seeking to facilitate their own friends."

Battery backup, multiple network failover, all highlight the need to specify a secure robust transit exchange shed where competitive local service providers (CLECs, in the Canadian terminology) can deploy the equipment they require to provide high-bandwidth services on the home gigabit network.

This would be equivalent to the Swiss guarantee of four dark fibres to each home - better in many ways as it would reach every home very quickly and it would not allow four monopolies to refuse entry to vertical market services.

type of service[edit]

"Karl Auerbach correctly points out that type of service traffic filtering was part of IP from day one, and always will be. It's a question of who defines the types and whether they do so with reference to bona fide functionality and life support requirements, or with some other agenda.

A regular public outreach such as Oregon held once to decide which medical services had highest priority might put citizens in charge of the type of service map used to decide packet throttling, failover priority or power outage coverage."

operational distinctions[edit]

We're just going to lose all these fights if we haven't made operational distinctions like the above. It's fine to have cute terminology (like "tails") to describe the configurations, but ultimately any such metaphor misleads - we have at least not to mislead each other on what the eventual configuration is we need.