FAQ & Troubleshooting
Carrier still throttles after the TTL fix
Most likely an IPv6 leak. The TTL fix only covers IPv4 packets. Either disable IPv6 on your laptop’s tether interface, or set the IPv6 hop limit too:
Windows
netsh int ipv6 set glob defaultcurhoplimit=65macOS
sudo sysctl -w net.inet6.ip6.hlim=65Linux
sudo sysctl -w net.ipv6.conf.all.hop_limit=65Speed test shows fast but YouTube is slow
Carrier is doing content-based throttling on video traffic (common with T-Mobile, AT&T). TTL won’t fix this — you need a VPN on your phone so the carrier can’t inspect what type of traffic it is. See Alternatives.
Is this legal?
Bypassing tether detection generally violates your carrier’s terms of service, but isn’t illegal in most jurisdictions. Worst case is the carrier throttling or cancelling your plan. Check your contract.
Will this break my normal Wi-Fi?
No. Setting TTL to 65 is well within the normal range (most stacks use 64 or 128). Every router and ISP handles it fine. You can leave the change in place permanently.
Why 65 and not some other number?
Your phone’s radio stack decrements TTL by 1 when forwarding. Phones natively send packets at TTL 64, so the carrier expects 64 to arrive at its towers. 65 − 1 = 64. Anything higher works too but looks unusual; 65 is the minimum that blends in.
All TTL commands in one place
Windows (PowerShell as admin)
netsh int ipv4 set glob defaultcurhoplimit=65macOS
sudo sysctl -w net.inet.ip.ttl=65Linux
sudo sysctl -w net.ipv4.ip_default_ttl=65