Hacker News Reader

Comment by Youden | Hacker News Reader

For anyone unfamiliar, PON means that several users will be physically spliced onto one shared fibre. In most of the deployments I'm aware of, it's 32 users per fibre. It also requires specific hardware, not standard off-the-shelf SFP modules like normal FTTH deployments.

I suggest "20 Gig" with PON should come with a massive asterisk; when you read "PON", you should think "Comcast" because you're about as likely to get the advertised speed from PON as you are from Comcast.

View on HN

> It also requires specific hardware, not standard off-the-shelf SFP modules like normal FTTH deployments.

What is a "normal FTTH" deployment? What percentage of residential deployments are PON versus non-PON? Because I was under the impression that PON was the (vast) majority of residential fibre deployments, in houses and apartments/condos.

And by 'standard OTS SFTP' do you mean Ethernet? Because the IEEE has their own PON standards, but also once you get outside the data centre, office building/tower, or campus, there are all sorts of 'different' technologies you tend to have to deal with WANs depending on distance.

We recently switched ISPs at work, and our 10Gb link was a BiDi single-mode fibre and we were provided with a media convertor from which we connected our router-firewall. Depending on distance desired you may (>80km) have to start getting into coherent equipment or optics (CWDM, -ZR).

>It also requires specific hardware, not standard off-the-shelf SFP modules like normal FTTH deployments.

Sorry this sentence doesn't make any sense unless it is US specific. There no such thing as "standard off-the-shelf SFP modules like normal FTTH deployments". And normal FTTH deployment around the is PON. Or specifically GPON.

Every single residential internet connection is sharing bandwidth one way or another. You are not owning a piece of the internet backbone.

I don't know of many places splicing in splitters. You can do it in a distributed split but distributed splits are a nightmare to maintain. We home run all endpoints to splitter cabinets to a patch panel. Then we patch the input fibers into splitters and then splitter output to house. This is all in a cabinet that a tech can walk up to and work on without tools.

> I don't know of many places splicing in splitters. You can do it in a distributed split but distributed splits are a nightmare to maintain.

Could this be dependent on geography?

Perhaps distributed (cascaded?) splits may be useful in less urban / more rural deployments where stringing a large number of strands over very long distances can be more pricey? Perhaps better to have x strands strung and patch in at any poles that are near residences?

* https://www.commscope.com/globalassets/digizuite/915282-taps...

* https://www.commscope.com/globalassets/digizuite/3101-optica...

* https://community.fs.com/article/centralized-splitting-vs-di...

We are pretty darn rural, not quite kansas rural. I guess the way we look at it is that the cable doesnt really cost anything in the grand scheme of things. Getting it built and maintenance really dwarfs the cable itself over time. Plus it allows you to do piecemeal upgrades to XGSPON instead of having to do an entire distributed split all at the same time. We can feed a splitter cabinet an XGS optic and patch each individual customer over as they upgrade. It just provides some better options at the cost of wasted fibers.

You're always sharing bandwidth. It's not like you have committed capacity end-to-end to every site on the Internet.

As much as I hate Comcast, I never had a problem getting the advertised speeds from them.

I'm on AT&T PON and I get higher than I pay for (I pay for 1Gbps and regularly get 1.2Gbps+ through a 5GBase-T link). It helps that I live in a small town and my neighbors aren't very noisy (in a networking sense)

What companies do "normal" FTTH deployments? My only other experience is with Quantum (née CenturyLink, née Quest), who definitely use GPON.

I know of a few coops that did active ethernet for future proofing after they got badly bitten by DSL. I doubt they even got that close to paying for the DSL rollout before they ended up ripping it all out for fiber.

Reply on news.ycombinator.com