# Change TTL Value

TTL determines the maximum router hops allowance before packets expire. Tuning this can optimize connectivity in some specialist scenarios like global roaming networks. The default TTL value (64) suffices for most users.

## What is the TTL?

TTL stands for "Time To Live"; it refers to the maximum number of mobile modem hops/routers a data packet can traverse before being discarded or dropped. TTL ensures packets don't circulate endlessly in routing loops.

The common TTL values used on a mobile modem are 64, 65, or 128.

* The default TTL 64 usually works perfectly for most mobile carrier networks.
* Higher TTL > 128 allows packets to travel further, which can maintain connectivity for international roaming. 
* Lower TTL < 64 may reduce latency and lag for long routes by forcing shorter paths. However, values below 30 can cause a loss of connectivity.

## Change the TTL Value

Our 4G and 5G routers allow us to change each interface's TTL value individually with a few clicks on the web page. Please follow the steps below to change the mobile modem's TTL value.

1. Go to "Network > Interfaces" after logging into the router.
2. Navigate to the "Mobile" interface and click the "Edit" button.
3. Tap the tab "Firewall Settings".
4. Choose a TTL value from 64, 65, and 128.\
   You can also click "-- Custom --" to input a custom TTL value.
5. Click the "Save & Apply" button on the bottom right corner.
6. Finally, perform a hard reboot by unplugging the power supply, waiting 30 seconds, reconnecting power to reboot the router, and reloading the settings from scratch.

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