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I hoped that with the fiber, which is naturally full-duplex medium, symmetrical speed would be obvious choice. But with advent of GPON, which is essentially hal
by zajio1am 5y ago
I hoped that with the fiber, which is naturally full-duplex medium, symmetrical speed would be obvious choice. But with advent of GPON, which is essentially half-dupex shared fiber medium, asymmetrical speeds make sense again.
Here, a provider i use offers variable tarrifs, that allow adjusting download/upload ratio dynamically in web interface (e.g. tarif '250' could be switched between 250/80 Mbps, 150/150 Mbps, or 80/250 Mbps).
- kornholi 5y agoAlthough GPON is shared, it is not half duplex! I'm not exactly sure why the asymmetrical version won out, perhaps due to cheaper optics back in the day? Latest iterations (NG-PON2 and XGS-PON) are 10G symmetrical, and XGS-PON is now cheap enough that GPON doesn't make much sense. AT&T Fiber in the US has been deploying it for the last few years.
- zajio1am 5y ago> Although GPON is shared, it is not half duplex! Seems like you are right! Although most are asymmetric (2488 / 1244 Mbps). I guess that even for ones with symmetric bitrates, effective upstream transfer rate would be lower than downstream transfer rate due to synchronization / higher inter-frame period needs.
- pabs3 5y agoI wish AON won over PON, since the latter isn't safe with an ONT/CPE controlled by the customer.
- MrRadar 5y agoI just signed up for fiber internet service at my new house and it's 940/940 symmetric. I'm 99% sure the service is some form of GPON so I don't think there's any inherent limitation that you can't have symmetric GPON.
- topranks 5y agoHeh that's interesting. I speculated about just such a possibility earlier in the thread - interesting to see someone doing it. What access technology is being used by that provider that you can change the up/down allocation?
- zajio1am 5y agoGPON