user109 It’s about layer 1 of the OSI model. Through direct access to the fiber to the end customer or Init7 has full flexibility regarding the usage unit. It could also “beam” quantum through the fiber 😂 or offer ⅒/25/50/100/400 Gbit/s or terabit internet, the physics of the fiber optic is basically the limit and not the layer 2 technology of it respective PON technology. With PON or GPON or XGS-PON you are bound to the limitations of the technology. The whole discussion and argument with the ComCo is not about PON vs. AON, but rather the topology (P2MP vs. P2P) of the fiber optic network between headquarters and end customers, so to speak about the discussion of where the splitters are located. Originally these were not only in the headquarters, but between feeder and drop or even in the BEP. So there is no chance for a competitor to get an ALO or Rent layer 1 access from the headquarters. You had to rely on Swisscom’s PON tree for better or worse, or you could buy your own PON tree between the headquarters and the usage unit for a lot of money as a cooperation partner (e.g. Salt). As a relatively small number, you would have had no chance of getting to Layer 1 and would have only had to purchase your services via BBCS from Swisscom and therefore via Swisscom’s technology (Layer ⅔). The nice thing about P2MP or PON is the possibility of saving fibers in the feeder. to make much better use of existing fibers. Swisscom would have to add fewer fibers and would certainly be able to expand more quickly. But that’s no longer up for debate, because a discussion about would have been couldn’t get us anywhere. The status of the old telephone network has now been restored, so to speak: one or even two direct connections (P2P) between the usage unit and the central office. PON or AON can be used flexibly by any provider in this central office. No technology is dictated.

Here is the structure at Init7:

The lower 4 switches of the access level are Cisco Catalyst with 48 SFP28 ports, where 1, 10 or 25 Bidi Gigabit Ethernet modules can be flexibly installed. The top two switches of the aggregation layer are also from Cisco and have 32 QSFP28 ports for 100 Gigabit Ethernet. Each switch is connected to an aggregation switch with 1× 100 Gigabit/s. So in this example, if we assume full occupancy with 50% 25 Gigabit/s and 50% 10 Gigabit/s (completely unrealistic, most customers are probably still on 1 Gbit/s):

• 0.5 * 48 * 25 Gbit/s = 600 Gbps
• 0.5 * 48 * 10 Gbit/s = 240 Gbit/s
• Total: 840 Gbit/s
• Uplink: 200Gbps
• Ratio on aggregation switch: 1: 4.2

Now the connection of the two aggregation switches, each with 1 × 100 Gbit/s, into the core network of Init7 comes into play:

• 4 access switches with 2 × 100 Gbit/s each (multimode AOC) on the aggregation switches: 800 Gbit/s
• Uplink per aggregation switch: 100 Gbit/s
• Ratio: 1:4

Total Ratio: 1: 16.8

Another advantage of the setup: off-the-shelf hardware and no proprietary telco equipment.

(I don’t know where these 4 DACs are going. Photos come from [https://ipng.ch/s/articles/2021/08/28/fiber7-x.html](https://ipng.ch /s/articles/2021/08/28/fiber7-x.html) )

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@cybi wrote:

Um, maybe a stupid question, but if I now order FTTH on demand from SC, is that also XGS-PON? Or is it AON?

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Only P2P is built. The provider of your choice decides on the technology and provides it at the headquarters. the POP or the point where your fiber “arrives”. If the control center is a POP, Init7 will use AON and Swisscom, Sunrise etc. will use XGS-PON. Many providers will offer advance services via BBCS from Swisscom and thus XGS-PON.

Whoaahh. You simply write too much, nobody wants to read who should (have to) still be working 😁

Just briefly: I cannot (and am not allowed to @user109) say exactly how our network is/will be structured.

• Much of what is written here is not entirely true.
• This means we can monitor the utilization of the PON trees through constant monitoring and use HU/KI (Human Intelligence with the help of AI) to decide when we want to expand the FAN uplinks many times over.
• The overbooking calculation here is a bit pessimistic.

About the distance:

• No, it doesn’t matter at all!
• The biggest problem is splices and the longer a fiber optic cable, the more such splices there are. Of course you try to avoid them as much as possible, but they are unavoidable if there are junctions.
• It is also known that these splices age, so the “attenuation” can increase over time.
• Further, SFPs lose their diode performance and become blind over time, which affects distance.

Strategy:

• Copper will be used for >10 years.
• In 2024 there will be a significant fiber push, even in rural areas where feasible (e.g. in my case 😁)
• There may be money from the federal government to develop areas that are not economically viable (first this has to be analyzed… and that will certainly take time)
• The development of remote areas can also be done using alternative technologies (SAT, 5G,…).
• 1 fiber per usage unit in the central office is enough (who the heck decided to install an OTO with 4 plugs)
• In the central office, this fiber can be switched to any of the ISP’s equipment. The comparison with POTS is good because xgsPON is also a type of TDM technology and only one line runs into the apartment.

It was short, right?

Many greetings and enjoy the holidays

Roger G

Question, according to this treat, Swisscom uses PON with 1:64 splitters and the splitters are probably now very often also installed in the control centre, because of the 2P2 design according to the specification. If everyone on a PON tree shares 10Gb/s up and down, that doesn’t leave much bandwidth per user. I realise that it is very often the case that not all 64 users (provided all 64 ports are occupied) are online or require a lot of bandwidth. However, I think that there are still bottlenecks and a certain amount of overbooking. Connecting the PONS to the backbone is certainly no longer a problem these days, there is certainly enough capacity available.

How are bottlenecks resolved, are additional PON ports connected and customers moved to another PON port?

Another question regarding PON. Does or will Swisscom also use WDM-PON? I know about 25PON or 50 PON, but I don’t know what impact this has on the available bandwidth on the individual PON port.

Greetings Tom

Tom_40 These are optical splitters. The market is moving towards NG-PON2 (also known as TWDM-PON). Mainly for the advanced network capabilities, less for the pure speed.

Hello together

Here you can read about it:

50 Gbit/s on a fixed line - world premiere!

https://www.swisscom.ch/de/about/news/2020/10/08-weltpremiere.html

Greetings Lorenz

Lori-77 Did I miss something? It’s 2025 now. World premiere was 2020.

user109

No, you didn’t, the link contains the year, it was previously about what doesn’t come after XGS PON, I just came across this link again.

What was once tested…..

You know yourself how few users effectively utilise the 10GB…..

Greetings Lorenz

user109

Thanks for the info and the link, I know this entry. However, it does not show how to react if rationing alone is not sufficient and a PON tree is really utilised over a longer period of time. The backbone is then not the problem as the PON tree is probably connected via a 100G/bits link.

Greetings Tom

user109

Thank you, I am interested in PON and the design of this network technology, hence the question. There are Youtube videos about it on the internet. But not how bottlenecks are counteracted or reacted to.

I currently have fibre optic and the M subscription and this is completely sufficient. Yes, the internet is definitely lagging behind the bandwidths available now.

Greetings
Thomas

Tom_40 Here is another official document from the ITU: https://de.scribd.com/document/537223958/T-REC-G-9807-1-201606-I-PDF-E#

Perhaps this is also interesting as an explanation. It is essentially explained from a German perspective, but technically there is no difference. GPON was/is not used in the Swisscom network.