I, too have CenturyLink fiber. I've got an hourly cron job to save the IP address of the "ppp0" interface. I've got a Linux machine doing routing instead of a modem. Since 2022-12-04, my IP address has changed 109 times. IP address usually does not change when I reboot my routing machine. I frivolously have not saved reboot timestamps.
Minimum 1 hour between addresses
Maximum 1512 hours
Mean 200 hours
MattSayar•1d ago
So yours updated about every 8-9 days compared to my (way shorter timeline experimental average of) ~40 days. I'm guessing ISPs officially want to err on the side of expecting your IP to change more often than not. Probably for CYA reasons
bediger4000•1d ago
I'm not convinced that CenturyLink knows what it's doing. Attributing CYA instead of bizarre incompetence is charitable.
I do not understand why they don't sell static IP addresses, either. They did that back in the DSL days. Also, why no IPv6? It's just weird.
MattSayar•1d ago
I understand not selling static IPs; there's only ~4 billion of them and >4B devices that need to connect to the internet. CGNAT is the best way ISPs have figured out to ration IPs lately. The IPv6 rollout is something I'd have to read a book about to understand why it's taking 30 years with little adoption.
bediger4000•1d ago
CenturyLink gives you an IPv4 address that's not NATted in any way, shape or form - it's a globally reachable IPv4 address, comes right out of CenturyLink's share of those ~4B addresses. Every single one of the 109 addresses I've recorded is not a "bogon", not 10/8, 172.16/20 or 192.168/16. I regularly ssh to my home server directly.
They're leaving money on the table by not renting them to people who want one.
Similarly, Comcast does IPv6 to its residential customers, and even tiny VersoNetworks in Denver can manage both IPv4 and IPv6 to its customers.
bediger4000•1d ago
Minimum 1 hour between addresses Maximum 1512 hours Mean 200 hours
MattSayar•1d ago
bediger4000•1d ago
I do not understand why they don't sell static IP addresses, either. They did that back in the DSL days. Also, why no IPv6? It's just weird.
MattSayar•1d ago
bediger4000•1d ago
Similarly, Comcast does IPv6 to its residential customers, and even tiny VersoNetworks in Denver can manage both IPv4 and IPv6 to its customers.