MikroTik

Hi all,

I'll like to make a TCP based tunnel to carry traffic (including UDP) through - is this possible? I think that normally PPTP is UDP based? Is EoIP also UDP based?

The reason I'm looking for this is that I don't want UDP traffic to get lost over a wireless connection due to interference - if I could have a TCP tunnel I would hope that no traffic *inside* the tunnel would get lost.

If anyone knows how to make a TCP based tunnel that would be great

thanks,

D

Assuming support at both ends, then SSTP should do the trick (http://wiki.mikrotik.com/wiki/SSTP). You may however have unexpected performance issues as TCP will wait for retransmits and this may impact the traffic inside the tunnel.

The reason I'm looking for this is that I don't want UDP traffic to get lost over a wireless connection due to interference - if I could have a TCP tunnel I would hope that no traffic *inside* the tunnel would get lost.

Though that would defeat the whole purpose of udp, you should be right. i guess udp traffic through a tcp tunnel, should be quite reliable. just bear in mind that it would be slower than streaming udp traffic without tunneling as not only the tunnel would encrypt the traffic by default but its also subjected to tcp handshaking. Also, tcp tunneling is not a good choice for tunneling tcp traffic as an effect called "tcp meltdown" could occur. why don't you consider using ipsec by the way? someone correct me if im wrong but ipsec should be able to protect any traffic over IP, not just tcp/udp. and by using AH header for example, you should be able to check the integrity of the packets as well. also, as far as i know, no such a thing as tcp meltdown, applies to ipsec traffic.

That should be tunneling over IP which includes TCP and UDP.
I would go for EOIP which is pretty straight and easy.
But anyway, what kind of UDP dropping are you experiencing? Just curios.

Its audio (SIP/RTP) that drops even though the link is "good" (good TX/RX good signal - maybe not perfect CCQ though). I've seen this before - I think interference on the unlicensed frequencies causes dropped/lost packets. This is no problem for any TCP traffic (HTTP/email/etc) but I think it shows with RTP/UDP. It only happens on some links (I'd bet the links with more interference). I have no bandwidth or latency problems because this traffic never leaves the local network so I can afford to introduce some latency and bandwidth overhead if I could eliminate UDP packet loss.

The thing is normal tunnels are UDP based arn't they (PPTP is GRE but isn't that over UDP transport?). I'm guessing EoIP might be the same (so no ACK/resends?).

I know I can do this kind of thing in Linux (VTUN with TCP transport) but obviously I'd much rather a Mikrotik solution rather than have to worry about messing with any other technology.

D

The thing is normal tunnels are UDP based arn't they (PPTP is GRE but isn't that over UDP transport?).

EoIP is based on IP protocol (Ethernet over IP) and GRE, GRE is also a tunnel over IP, so no UDP.
I find it hard to believe that there are tunnels over UDP, because of the nature of UDP itself, but I am no expert in tunnels.
Anyway, best way is to give it a try.

EoIP is based on IP protocol (Ethernet over IP) and GRE, GRE is also a tunnel over IP, so no UDP.
I find it hard to believe that there are tunnels over UDP, because of the nature of UDP itself, but I am no expert in tunnels.
Anyway, best way is to give it a try.

Actually UDP tunneling exist and are better choice than TCP tunneling specially for tunneling tcp packets. although routeros doesn't support it at this point, but openvpn is perfectly capable of tunneling over udp for example. as for GRE, GRE tunnels are stateless, just like UDP. so i believe a UDP stream inside of a GRE tunnel (like EoIP or PPTP) , could not guarantee any delivery. that being said, im no expert on these subjects. maybe someone else could shed some more light on this matter.