# Mobile Modem

- [Switch SIM Card](/mobile/switch-sim-card.md)
- [Mobile Watchdog](/mobile/mobile-watchdog.md): \[Exclusive] Mobile internet guardian program and automatically keep mobile modem alive.
- [Mobile Protocol](/mobile/protocol.md): Mobile protocol enables session management, authentication, and IP connectivity to transport data over high-speed cellular networks.
- [APN Setting](/mobile/apn.md): Accurate APN settings are crucial for successfully establishing connectivity on a mobile network.
- [Mode & Band Locking](/mobile/band.md): Locking 4G/5G Router's Modes and Bands
- [Modem Diagnosis](/mobile/dx.md): Validate mobile connectivity and determine if SIM card, signals, APN settings troubleshooting needed.
- [Change TTL Value](/mobile/dx/ttl.md): With individual control over the IP packet lifespan per interface, you can optimize TTL best to suit the type of connected devices and usage profiles.
- [Detach Reattach](/mobile/dx/detach-reattach.md)
- [Fix PLMN Error](/mobile/dx/plmn-error.md): PLMN is the core identifier for the mobile network that allows cellular devices like modems to identify and connect to specific carrier networks globally correctly.