On Wed, Oct 26, 2016 at 5:36 PM, Mikael Abrahamsson <swmike@swm.pp.se>
wrote:

> On Wed, 26 Oct 2016, Jan Ceuleers wrote:
>
> What I mean is that the OLT optics become very expensive if you need to
>> support as many lambdas as you have customers. You'd furthermore need an
>> OLT port for much fewer customers (e.g. 1 port per 64 or 128 customers)
>> than the thousands you can support on a (shared) GPON port on a single
>> lambda.
>>
>
> That only works if your customers don't use their Internet access very
> much. If they do, you're in trouble and have to rebuild.
>

Yes, and the question then becomes: How much is "very much"? This can of
course be analyzed mathematically, which e.g. Google have done here:

http://research.google.com/pubs/pub44935.html


>
> In my market, we're now in the access speeds where 100/10 is on the lower
> end of access, and it's not uncommon for people to have 250, 500 or 1000
> downstream. If they then actually start using their bw then you'd have to
> rebuild to either go higher speed for some CPE (complicated and expensive),
> or rebuild to have smaller splitter domains.
>

The standard answer from PON proponents (I'm not one) is to upgrade
equipment, from GPON to XG-PON or NG-PON2. But upgrading hardware as
bandwidth demand increases is necessary whatever the technology - what's
important is the scalability of the solution.