1. Change default administrator password to another complex and strong one;
2. Open router firewall;
3. Change remote control port to not common used, for example 8086 and set the only IP to access;
4. Disable telnet;
5. Disable IP directional boradcast, disable IP route and IP Redirection
Ping and tracert use the ICMP protocol. You can drop all ICMP type packets using specific firewall rules for this purpose.