Hello, I am currently comparing different IP-tunneling protocols/implementations, and have stumbled upon something I am not able to explain. Regardless of which tunneling technology I use, the latency increases with a couple of 10s of ms and I see a significant degradation of throughput (compared to when no tunnels are used). The only exception is IP-in-IP, where I get similar performance with and without tunnels, but it does unfortunately not work in my scenario. First, I thought this was caused by the different tunneling software, but after measuring the processing time of the applications (xl2tp and pptp-client) and when the packets are seen by the different iptables chains (using LOG), these delays seem to be acceptable. However, one delay sticks out. After the packet has been decapsulated and fed to PPP, it takes a "long" time before it is seen again. My question is, can PPP be the cause of the higher latency and lower throughput? Similar observations are made at both ends of the tunnel. Thanks in advance for any help, Kristian -- To unsubscribe from this list: send the line "unsubscribe linux-ppp" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
