what do you mean by 'merging'? do you expect double throughput just because you have two ADSL lines?

if i had to lines the 1st one is 4 MB ,the 2nd is 4MB
i want to merge the two lines to get a speed 8MB

Do you want create a connection PtP at 8Mbps or do you want to access to internet at 8Mbps ?

i want to access the internet with speed 8MB by using 2 lines adsl each one 4MB

You can not do it, each ADSL has own IP and you can not bonding (with round-robin policy) the two interface.
If you have remote server, you can make a VPN layer 2 for each ADSL and create a bonding interface over two VPN. This model requires a remote server where to terminate the 2 VPN.

you can't merge them, but you can make load balancing or try PCC

soo hwo to make load balancing???

start with PCC, read this carefully
http://wiki.mikrotik.com/wiki/Manual:PCC

is the load balancing a hardware device?
and can we write these commands with two routers have a different lines for example
i had two routers
the 1st one has gateway 192.168.1.1 (1st line)
the 2nd one has gateway 192.168.2.1 (2nd line)

and
the local interface is 10.0.0.2 (for users)
the server interface is << 192.168.1.100 , 192.168.2.100 >>

can i apply this commands (the script) for these routers ???
like these
/ ip address
add address=10.0.0.2/24 network=10.0.0..0 broadcast=10.0.0..255 interface=LAN
add address=192.168.1.100/24 network=192.168.1.0 broadcast=192.168.1.255 interface=ISP1
add address=192.168.2.100/24 network=192.168.2.0 broadcast=192.168.2.255 interface=ISP2

Admin of mikrotik
I already make what do you tell me to do
but there is aproblem
when i open the interfaces ether1 (ISP2 in the script) hasn't Tx or Rx transfer
can you tell me what's the problem
here is the pic

Pictures really do not ever give enough information to be helpful for these kinds of setups. They do not display all of the information needed. Read this thread here and follow it on how to post properly to get the best help.

http://forum.mikrotik.com/viewtopic.php?f=13&t=45259

I figured out from answers that I can not merge to Internet connections (ISP) into one high-speed Internet connection and access from local client in network. Generally this is when I want to download something via FTP or HTTP because single connection with destination will be created and single ISP connection will be used, right?

But what about torrent clients? As I know torrent client makes some number of connections to different destinations (multiple connections) and can they be distributed (load balanced) over two ISP connection and increase speed of downloading?

Yes, because torrents make several connections to several locations, with PCC as the load balancing method with the correct matcher, they will be spread out across several links. No one connection however will exceed what a link is physically capable of.

Thanks to all of you!!! This thread clarified my doubts so I am going to buy RB750G and make my "speed" home network.

Similarly read this configuration and perhaps a different explaination will help you understand it more

http://www.mikrotik-routeros.com/?p=12

Similarly read this configuration and perhaps a different explaination will help you understand it more

http://www.mikrotik-routeros.com/?p=12

Yes, I know what is PCC scenario but my concerns were about "merging" connections. I have lived in fallacy since today that mine Linksys RV042 can "merge" connection for Internet because seller in retail shop told me that 5 years ago. RV042 is "dead" and I need to change it with similar device. Today I found out (I read some very old datasheets) that I haven't had "merged" connections except when download torrents but my personal needs were torrents in 85% of cases and I was satisfy with performance. I noticed problem couple days ago when I was downloading Lion for OS X I noticed that speed is limited with single connection speed so I figured out what I wrote above. That is my problem and why I'm asking for RB features.

Anyhow, thanks again for helping me.

Correct, the only way you can merge connections is using something like MLPPP if your ISP supports it, or end to end bonding over private links.

Load balancing can double the speed of browsing the internet because each browser open multiple connections to get items of pages quickly Am I right?
Can I have links to MLPPP and end to end bonding over private links.?
What if I install MK on virtual machine then route 36 pc to this machine. Is this scenario correct?

thanks a lot

Load balancing can double the speed of browsing the internet because each browser open multiple connections to get items of pages quickly Am I right?

Improve a little, maybe. No, not "double".

Thanks Mr. Normis
But regard the following question:
What if I install MK on virtual machine then route 36 pc to this machine. Is this scenario correct?
I mean make MK as a guest on XP pro then make this as gateway
I hope my words understood

yes, it's possible

I forget to tell you that this scenario will be deployed in an internet cafe, my machine will be like :2000 core 2 due , 2 Giga ram, 80 G hd.
is this hardware enough for PCC method and queue tree download for 32 Pc's?

Sorry if I bothered you...

Load balancing can double the speed of browsing the internet because each browser open multiple connections to get items of pages quickly Am I right?

Improve a little, maybe. No, not "double".

Excuse me Mr. Normis .. I think pcc be able double the speed if client download with IDM. I've proved it.

I forget to tell you that this scenario will be deployed in an internet cafe, my machine will be like :2000 core 2 due , 2 Giga ram, 80 G hd.
is this hardware enough for PCC method and queue tree download for 32 Pc's?

Sorry if I bothered you...

A 450 or 450G would be more than enough for that situation, so for your current hardware, yes that is more than enough for what you are looking at.

Thanks Mr. Feklar. I am going to install it in our company.

Load balancing can double the speed of browsing the internet because each browser open multiple connections to get items of pages quickly Am I right?

Improve a little, maybe. No, not "double".

Excuse me Mr. Normis .. I think pcc be able double the speed if client download with IDM. I've proved it.

can you tell me how Mr bambangs2komputer

BGP is the only solution for "merging" 2 Internet connection, but this should be supported by your ISP and you need an AS number for that.

Load balancing will determine simultaneously usage of Internet connection, but they will keep having individual IP address and network functions.

BGP is the only solution for "merging" 2 Internet connection, but this should be supported by your ISP and you need an AS number for that.

Load balancing will determine simultaneously usage of Internet connection, but they will keep having individual IP address and network functions.

can you give me the way to do this

The issue of AS numbers is very restricted and is not likely in order to "bond" two ADSL connections - not even clear that the ADSL connections have public IPs.

The real choice is:

a) combine the bandwidth using a method supported by the ISP or by a 3rd party (e.g. VPN method), or

b) use a form of load balancing as suggested earlier in the thread.

c) create IP or EoIP tunnels back over each of the ADSL connections to your data center, put these interfaces as slaves of a bonding interface at either end.
There you have merged ADSL's at the cost of tromboning traffic from the site out to the internet, back to your data center and back out to the internet.

This is a workable solution if:
1. you have low latency between the ADSLs and the data center where you plan to do this
2. all the adsl lines have the same sync speed; rr bonding does not deal well with different speed interfaces.

I have this working on a site with 4 x ADSL2 links syncing at 22Mbps/2.1Mbps each. Aggregate throughput over the bonded link is around 68Mbps/7Mbps and this is what I shape it at however the former is reduced simply because the provider of these links cannot supply the full 22Mbps in peak times.