With a few rare exceptions (like VPN Fusion which is replaced by VPN Director), Asuswrt-Merlin retains the features from the original stock Asus firmware. In addition, the following features have been added or enhanced:
System:
- Various bugfixes
- Performance optimizations to some CPU-bound components like OpenVPN
- Some components were updated to their latest versions, for improved stability and security
- User scripts that run on specific events such as firewall restart
- Cron jobs for scheduled tasks
- Customizable config files for router services
- Third party software through Entware, with an easy setup script
- SNMP support (some models)
- Nano text editor (for more user-friendly script editing)
- NTP daemon, which can synchronize your client devices
- Third-party addons, with a management interface (AMTM)
Disk sharing:
- Optionally use shorter share names (folder name only)
- NFS exporting of USB drives
Networking:
- Act as a SMB Master Browser
- Act as a WINS server
- SSHD support for key-based authentication
- Allows tweaking TCP/UDP connection tracking timeouts
- CIFS client support (for mounting remote SMB share on the router)
- Advanced OpenVPN client and server.
- Netfilter ipset module, for efficient blacklist implementation
- Wireless site survey page
- DNS Director , enforcing a specific DNS server, can be applied globally or per client
- Custom DDNS (through a user script)
- TOR support, individual client access control
- Policy-based routing for OpenVPN clients (based on source or destination IPs), sometimes referred to as "selective routing", or "split tunneling")
- Detailed wireless troubleshooting information (on some models)
- Redirect NTP client queries to the router's own NTP daemon
- Cake SQM QoS (on newer HND models)
Web interface:
- Performance improvements
- Optionally save traffic stats to disk (USB or JFFS partition)
- Enhanced traffic monitoring: adding graphical charts, and traffic monitoring per client IP
- Hostname field on the DHCP reservation list and Wireless ACL list
- System info summary page
- Wifi icon reports the state of both radios
- Wireless site survey
- Advanced wireless client list display, including automated refresh
- Redesigned layout of the various System Log sections
- Editable entries (on some pages)
Some features first debuted in Asuswrt-Merlin and were eventually implemented in the official firmware:
- HTTPS configuration interface
- Persistent JFFS partition
- LED control - put your router in Stealth Mode by turning off all LEDs
- Turning WPS button into a radio on/off toggle
- Clicking on the MAC address of an unidentified client will do a lookup in the OUI database.
- WakeOnLan web interface (with pre-configured targets)
- Display active/tracked network connections
- VPN Status page
- DualWAN and Repeater mode (while it was still under development by Asus)
- Basic OpenVPN (client and server) support
- Configurable IPv6 firewall
- Improved compatibility with 3TB+ and Advanced Format HDDs
- SSH access
- Disk spindown after user-configurable inactivity timeout
- Updated Samba version (3.6), with SMB2.0 support
- TLS 1.3 support for some services (OpenSSL 1.1.1)
- Modern DDNS client (In-a-Dyn), with https support
- Full cone NAT support (on some models)
- User-provided SSL certificate
- Display the Ethernet port states
- TLS support for the FTP server
- Allow or disable WAN access to the FTP server
- User-defined options for WAN DHCP requests (required by some ISPs)
- DNS-over-TLS
- DNSSEC validation