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@WalterB wrote:

@AsianCoke

This is interesting because 10Gbit/s is displayed and this information is usually very accurate, now the question is whether the speed test has a problem.

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It is quite possible that the Swisscom speed test server currently has a problem, but otherwise the 10 Gbit/sec is only the maximum sync value of the line and not the actual available performance of an individual connection at any time.

It would actually be better to simply write down the connection type XGS-PON, because:

- max. it’s only about 8.4 Gbit/sec anyway

- The 8.4 Gbit is distributed over up to 32 OTO connections for the end customers (three neighbors who are speed testing at the same time, so the test results are divided into thirds)

- Every node in the Swisscom backbone and then further on in the Internet bundles tons of individual lines and, purely from a network perspective, average loads are always taken into account and not peak values, so every hop is overbooked by very large factors.

1.: Do you do the speed test directly in the IB3 menu (which browser) or via the app?

2.: Up and Down are completely identical. That’s strange -> It also goes against the theory that it depends on the utilization of the “tree”. Without insinuation: it’s not fake, is it?

3.: XGS-PON can reach approximately 8.x GBit/s. It is explained somewhere in the forum why this is the case.

4.: The attenuation value for Down is much too high. This means that your fiber optic cable was not processed completely cleanly somewhere. But I can’t say whether that really has an influence.

Call the hotline. They should check your Anschluss. If necessary, ask for the 2nd level if the 1st level is overwhelmed and tells you stories about something else.

OK. Then call the hotline. Something is wrong there.

By the way, the attenuation value in the DS is completely normal for XGS-PON (Guido mistakenly compared this with FTTH P2P, which has lower values), but of course it still can’t hurt to talk to support about a brake that may be present by mistake.

By the way, here is a link to a CNLab article on the subject of speed testing with XGS-PON:

https://ux.cnlab.ch/benchmarking/news/10g-bechmarking

5018 the fiber optic values ​​are OK.

I think the port on the OLT is stuck.

these are my XSPON values:

This is what it looks like in the ideal case

@Roger G what is the problem with @AsianCoke

P.S. It’s no longer a secret (see tweets from Fiber7) that all OLTs are only connected at 10 or 20 Gbit/s.

In practice, only a maximum of 1 GBit/s is possible anyway. With the AWS S3 I only managed a maximum of 500 Mbit/s without a special line for which you pay something. I achieved 1 Gbit/s with the Gopro Cloud.

OK @user109 Thanks.

@Roger G is Mr. Kupfer. His FTTH colleague (D….) is not in the forum (I think).

And what Fiber7 wants to sell as a great discovery has never been a secret, because the connection is always based on capacity. If it becomes necessary, further expansion will be carried out. It’s always been like that. Otherwise, you’re just installing equipment that costs a lot of money and is already outdated by the time you really need it.

@5018 ahh ok, thanks for the info (Roger G.).

I’ve known it for a lot longer than Freddy with the OTL connection, because I’m constantly on the move in the headquarters and large VT’s and overbooking is avoided up to 2.5 Gbit/s on average.

Of course I would know where to call to reach a specialist for such scenarios, but unfortunately I can’t make that public here. With the hotline it’s sometimes like a lottery game in a case like this.

POGO 1104

This is the reception level and not the attenuation. According to the ITU standard, up to -28 dBm would be in the green range, but many ONUs are even more sensitive (even higher values ​​would work).

@foobar I can’t confirm that from practice with the -25 dB. I have had several customers with -25 to -28 dB in the DN and -20 dB in the UP. This line was very unstable and did not deliver full performance.

The dB refers to the line attenuation and not the transmission power/reception level.

No, the power level is not attenuation and, according to Swisscom quality requirements, this may be a maximum of -25dBm (XGS PONy) and -15dBm for P2P.

There is also the value 0.25dB, which actually means the maximum permitted attenuation of the fusion splice.
Yes, stupid, these are the same numbers that describe different things.

You can get confused at times.

@user109

dBm is always a power (dB related to 1 mW)

dB would be attenuation.

It is clear that it is borderline at -28 dBm… that is based on a BER of 10^-3, then the FEC often stumbles (10^-12?)

@foobar Thanks, now I see it a little more clearly.😁

Nice discussion, but doesn’t help the customer at all. You should mark it as offtopic. 😉

But it’s certainly out of the category: learned something again.

Unfortunately, I can’t see the Anschluss because @AsianCoke is not connected to a customer account and I haven’t received a response to the PM either.

And yet Guido, Roger can also do fiber, LOL 🤣

It was clear to me that you could do that, but it wasn’t clear to me whether you wanted to do that 😉

@AsianCoke wrote:

My Internet Box 3 only achieves 2.4 gbit down/up. The fiber cable and SFP for 10gbit is installed in the box and connected to the power box. What can you do there?

Maybe replace the Swisscom Internet Box with hardware that also supports 10 Gbit/s Ethernet ports in the home network (LAN)? For example Zyxel AX7501:

[https://community.swisscom.ch/t5/Router-Hardware/Zyxel-AX7501-im-Bridge-Mode-Wie-ist-WAN-bei-pfsense-zu/m-p/655466] (https://community.swisscom.ch/t5/Router-Hardware/Zyxel-AX7501-im-Bridge-Mode-Wie-ist-WAN-bei-pfsense-zu/m-p/655466)

[https://community.swisscom.ch/t5/Internet-Allgemein/Erste-Experiences-mit-10-Gbit-s-XGS-PON-Anschluss/m-p/654872#M61777] (https://community.swisscom.ch/t5/Internet-Allgemein/Erste-Experiences-mit-10-Gbit-s-XGS-PON-Anschluss/m-p/654872#M61777)

[https://www.studerus.ch/de/products/zyxel-ax7501-with-xgspon-sfp/](https://www.studerus.ch/de/products/zyxel-ax7501-with-xgspon-sfp /)

Operating XGS-PON “forced hardware” is generally recommended in bridge mode. Only “forced hardware” can/may/should be used on a Swisscom XGS-PON fiber optic connection, which is listed in the document “E_BBCS_Supporting-Document_Proved_Equipment”:

[https://www.swisscom.ch/dam/swisscom/en/ws/documents/E\_BBCS-Documents/e\_bbcs\_supporting-documentprovedequipment.pdf](https://www.swisscom.ch/dam/ swisscom/en/ws/documents/E_BBCS-Documents/e_bbcs_supporting-documentprovedequipment.pdf)

https://www.swisscom.ch/de/business/wholesale/angebot/anschluesse/BBCS.html

> Expand “Auxiliary documents”.

An introduction to the topic of “10 GBit/s in private households” offers:

https://community.upc.ch/d/16951-10-gb-abo/2

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@foobar wrote:

It is clear that it is borderline at -28 dBm… that is based on a BER of 10^-3, then the FEC often stumbles (10^-12?)

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The dependence of BER and RTT for TCP connections on the maximum achievable data transfer rate can be calculated using Switch’s “TCP Throughput Calculator”. Enter BER (Loss) and RTT in the “Calculate theoretical network limit” section and the calculator will calculate the maximum achievable data transfer rate with TCP connections.

https://www.switch.ch/network/tools/tcp_throughput/

- Ordinary Swiss Internet connections use an MTU of 1500 bytes for IPv4. The input value for MSS should therefore be left at 1460 bytes.

- Ordinary Swiss Internet connections have a bit error rate (BER) < 1E-8 (1e-06% = 0.000001%). Measured in the receiver after forward error correction (FEC).

- The faster the Internet connection, the higher the bit error rate (BER) requirements. The faster the Internet connection, the smaller the value of the maximum permissible bit error rate (BER). This dependency also applies directly to the value of the maximum permissible packet loss rate for TCP connections (=> TCP retransmissions).

- For servers located far away (high RTT values), the bit error rate (BER) requirements are significantly higher than for nearby servers (low RTT values). The same applies to the packet loss rate or the rate of TCP retransmissions.

Behind the calculator in the “Calculate theoretical network limit” section is the Mathis equation. See:

[https://de.wikipedia.org/wiki/Reichbreite\_(Radio Technology)](https://de.wikipedia.org/wiki/Reichweit_(Radio Technology))

[https://fasterdata.es.net/network-tuning/tcp-issues-explained/packet-loss/](https://fasterdata.es.net/network-tuning/tcp-issues-explained/packet-loss /)

[https://mobilecommunity.ch/wbb/index.php?thread/326-salt-fiber-oder-salt-unlimited-surf-f%C3%BCr-heimnetzwerk/&postID=2526&highlight=paketlossrate#post2526] (https://mobilecommunity.ch/wbb/index.php?thread/326-salt-fiber-oder-salt-unlimited-surf-f%C3%BCr-heimnetzwerk/&postID=2526&highlight=paketlossrate#post2526)

BER -> https://de.wikipedia.org/wiki/Biterrorh%C3%A4ufigkeit

RTT -> [https://de.wikipedia.org/wiki/Package circulation time](https://de.wikipedia.org/wiki/Package circulation time)

MTU -> https://de.wikipedia.org/wiki/Maximum_Transmission_Unit

MSS -> https://de.wikipedia.org/wiki/Maximum_Segment_Size

The bit error rate (BER) or the packet loss rate of a TCP measurement can be measured, for example, with CNLab measurements. See:

[https://community.upc.ch/d/15729-unifi-dream-machine-pro-und-durchsatz/9](https://community.upc.ch/d/15729-unifi-dream-machine- per-and-throughput/9)

[https://community.upc.ch/d/15729-unifi-dream-machine-pro-und-durchsatz/26](https://community.upc.ch/d/15729-unifi-dream-machine- per-and-throughput/26)

On the topic of “CNLab server for fiber optic internet connection > 1 GBit/s” see post no. 90 at:

[https://community.swisscom.ch/t5/Internet-Allgemein/Erste-Experiences-with-10-Gbit-s-XGS-PON-Anschluss/m-p/669358#M62728] (https://community.swisscom.ch/t5/Internet-Allgemein/Erste-Experiences-with-10-Gbit-s-XGS-PON-Anschluss/m-p/669358#M62728)

and post no. 21, as well as:

https://community.upc.ch/d/6897-extrem-holprige-connection/5

Alternatively, the packet loss rate or the rate of TCP retransmissions (TCP retransmissions) can be measured using the network measurement tool IPerf3. See the IPerf3 section at:

https://community.upc.ch/d/8569-gigaconnect-aussetzer/25

and the contributions:

https://community.upc.ch/d/8740-giga-connect-box/63

https://community.upc.ch/d/8481-gigabox-massive-lagspikes/7

The reference to ECN should also be taken into account for IPerf3 measurements:
[https://community.upc.ch/d/15729-unifi-dream-machine-pro-und-durchsatz/26](https://community.upc.ch/d/15729-unifi-dream-machine- per-and-throughput/26)

For IPerf3 measurements on fiber optic Internet connections > 1 GBit/s, the IPerf3 information is available at:

[https://community.swisscom.ch/t5/Internet-Allgemein/Pfsense-XGS-PON-IPv6-Swisscom-TV-und-weiteres/m-p/676191#M62947] (https://community.swisscom.ch/t5/Internet-Allgemein/Pfsense-XGS-PON-IPv6-Swisscom-TV-und-weiteres/m-p/676191#M62947)

to note!