All routers have a basic firewall. Some low-end routers offer only basic firewall functionality, while some high-end models include more sophisticated tools for protecting your home network from hackers and other threats. Some offer the basics while others offer advanced features like application-layer filtering and stateful packet inspection (SPI). The best way to protect yourself from spam, viruses, or other threats is with a hardware firewall that's built into your router. These routers have powerful security features that give you peace of mind when it comes to safeguarding your information while online.