Router which can modify TTL

Solution 1:

I assume that your problem is, that all incoming packets have a TTL of 1 which results in their deletion by the router. Clever idea of your ISP :)

Anyway if you use alternative router firmware like DD-WRT, OpenWrt, etc., you should be able to modify the firewall (iptables) rules to set the TTL to a different value (iptables has a --ttl-set option). The DD-WRT wiki has some information about that: http://www.dd-wrt.com/wiki/index.php/Iptables#Modifying_the_TTL

Solution 2:

Indeed there are some small ISPs (neighborhood size) which link you directly to their equipments over Ethernet cable and they set TTL=1 in the DHCP packets.

Authorization in their network is based on MAC address of your network card.

They also state that you are not allowed to use a home router unless you buy a higher subscription (lame).

As a possible solution:

• I have an Asus WL 500gp V2 wireless router for which I am planning to install OpenWRT so can I have a small linux box I can connect to using ssh where I can change TTL settings of my outgoing packets.