https://blog.wongcw.com/2022/10/06/%e8%81%af%e7%99%bc%e7%a7%91%e6%97%97%e4%b8%8b%e9%81%94%e7%99%bc%e7%a7%91%e6%8a%80%e7%99%bc%e5%b8%838gbps-xgs-pon%e5%85%89%e7%ba%96%e5%9b%ba%e7%b6%b2%e5%af%a6%e6%b8%ac%e5%83%853ms%e4%bd%8e%e5%bb%b6/