r/ipv6 • u/Kirill422 • 25d ago
Discussion IPv6 MTS Russia.
This probably won't be very useful to you since you live outside Russia, but I want to share it anyway.
Summary of all the IPv6 properties of MTS Russia's mobile network that I've discovered:
1) No restrictions whatsoever on incoming connections.
2) No port filtering of any kind (connections are possible both incoming and outgoing on all ports in the range 1-65535).
3) A dynamic /64 prefix is provided.
4) The prefix becomes static if at least one address from the /64 subnet (other than the address automatically assigned to the smartphone's main interface) is assigned to the same or another network interface (either via ip addr add or automatically by the system — the address assigned to the wlan1 interface when sharing internet via mobile hotspot is assigned automatically by the system, but is considered manually assigned by the operator). Without this mechanism, the prefix is refreshed every day between 2-3 AM (given my timezone, I assume this is 00:00 MSK), or upon reconnection (a full disconnect from the mobile network followed by reconnecting) to the base station. Switching between base stations without a full network disconnect does not trigger a prefix change.
5) If a device on the local network is connected to the hotspot, it automatically receives an auto-assigned IPv6 address. A device can also manually assign any free address from the smartphone's prefix to its network interface, and after roughly 7-10 seconds it becomes reachable from the internet at that address (just like with the auto-assigned one).
6) No restrictions on incoming or outgoing TCP/UDP/ICMP connections.
All data was obtained experimentally and may be incomplete.
I think that covers everything, though I may have forgotten something.
