I have two WAN links of same speed.
I want to dedicate WAN2 for UPLOAD. How this can be done?
An article on WIKI doesn't work, browsing stopped after implementing it.

http://wiki.mikrotik.com/wiki/Upload_wa ... ad_another [Not work]

You can not do that, in any way.

Example: If you upload by wan2, you ALSO MUST DOWNLOAD the control packet of TCP connection...

Hmmm v.sad I over expected the Mikrotik can do any thing (except doing laundary and making tea) , however its my mistake to over expect thing that are not possible. but still i m looking for wan up/down routing.
Anyway thank you Mr. rextended for your quick response

It is perfectly possible to do this if you have your own IPs and have peering with multiple upstream providers. TCP neither knows nor cares which path the packets took.

The problem arises if you are trying to do this on NATed connections using the IPs provided by the ISPs.

It is perfectly possible to do this if you have your own IPs and have peering with multiple upstream providers. TCP neither knows nor cares which path the packets took.

The problem arises if you are trying to do this on NATed connections using the IPs provided by the ISPs.

Can I make a search on google by 1.2.3.4 for example, and google send the result to 4.5.6.7?

It is perfectly possible to do this if you have your own IPs and have peering with multiple upstream providers. TCP neither knows nor cares which path the packets took.

The problem arises if you are trying to do this on NATed connections using the IPs provided by the ISPs.

Can I make a search on google by 1.2.3.4 for example, and google send the result to 4.5.6.7?

The problem isn't using two WAN links - it is using IPs associated with those WAN links. The OP did not make their situation clear so what I am saying is that you can certainly use different WAN links for upload/download and the TCP traffic can flow up on one and down on the other but that assumes that you are using your own IPs.

So - this can be made to work in business/ISP installations but less likely on home/small office installations due to the use of the WAN IPs provided by each ISP.

It is perfectly possible to do this if you have your own IPs and have peering with multiple upstream providers. TCP neither knows nor cares which path the packets took.

The problem arises if you are trying to do this on NATed connections using the IPs provided by the ISPs.

Can I make a search on google by 1.2.3.4 for example, and google send the result to 4.5.6.7?

The problem isn't using two WAN links - it is using IPs associated with those WAN links. The OP did not make their situation clear so what I am saying is that you can certainly use different WAN links for upload/download and the TCP traffic can flow up on one and down on the other but that assumes that you are using your own IPs.

So - this can be made to work in business/ISP installations but less likely on home/small office installations due to the use of the WAN IPs provided by each ISP.

The point is another, do not answer more complicated than user can understand.
Is possilbe to download from one and upload to another? The answer is NO.
Both of us know that is not really true, but in this case, is right to say no.

Both of us know that the IPv4 are not really depleted, but are correctly used only the 70%...
But for IPv6 is better say that IPv4 is finished...

The user also not understand/noticed this on wiki:

This method may not work, if your second provider does not allow packets with spoofed/different source address.

and you pretend to answer with peer?

BEFORE ANSWER, PLEASE READ MY SIGNATURE....

I think it is better to let people know when something does work, when it does not work and let them apply that to their own situation. That is how people learn.

The user asked if it was possible to use one ISP for upload and another for download. If you are using your own IPs with two BGP peered ISP connections then sure it is. If you are at an ISP peering point then it is even common. If you are trying to do so with a couple of local telco XDSL connections - then it most likely will not work.

Maybe it is a language issue but the original reply suggested that wasn't in any way possible which doesn't really tell the whole story.