Hello, If some extra information is required to be sent with each packet then does that require to change Ethernet MTU 1500 to 1500-(Bytes in extra info) or its ok with 1500 value of MTU? While checking source code of net_init.c in drivers/net dir i found one function eth_change_mtu. I want to know does that helps? why its given there in source code? regards, Harsh. static int eth_change_mtu(struct net_device *dev, int new_mtu) { if ((new_mtu < 68) || (new_mtu > 1500)) return -EINVAL; dev->mtu = new_mtu; return 0; } - : send the line "unsubscribe linux-net" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html