Bridge ADSL Modem/Router to Mikrotik Router

Dear Professionals
I’m having problems with making IPsec tunnel between two offices. I asked a question the other day about IP. Now, I’ve found that I can bridge the ADSL modem to my RB450G in order to get rid of the IP that My Modem gives to the router.

So, I can easily put my Zyxel or Maxnet Modem on Bridge mode. What I don’t understand is how to set up the RB450G to be able to dial the PPPoE connection.

This is what I did so far:

1.Created a ppp profile with change TCP MSS= yes
2.Created a PPPoE Client with my username and password from my ISP and assigned the aforementioned profile to it.
3. I went to the IP addresses and deleted the IP that was given to router by the modem.
4. IP Firewall NAT and masqueraded the pppoe interface
At this point I can see my public IP in addresses and I can connect to the internet, however I can no more connect to my modem and I’m afraid that someting is wrong and my security is at exposure.

Here’s my detailed options:

PPPoE Client

admin@MikroTik] /interface pppoe-client> print
Flags: X - disabled, R - running 
 0  R name="pppoe-out1" max-mtu=1480 max-mru=1480 mrru=disabled 
      interface=ether1-gateway user="xxxxxxx" password="yyyyyyyyyy" 
      profile=ppp-wan service-name="" ac-name="" add-default-route=yes 
      dial-on-demand=no use-peer-dns=yes allow=pap,chap,mschap1,mschap2



[admin@MikroTik] > ip firewall nat print
Flags: X - disabled, I - invalid, D - dynamic 
 0   ;;; default configuration
     chain=srcnat action=masquerade out-interface=ether1-gateway 

 1   ;;; default configuration
     chain=srcnat action=masquerade out-interface=pppoe-out1



[admin@MikroTik] > ip address print
Flags: X - disabled, I - invalid, D - dynamic 
 #   ADDRESS            NETWORK         INTERFACE                              
 0   ;;; default configuration
     192.168.88.1/24    192.168.88.0    ether2-master-local                    
 1 X 192.168.1.3/24     192.168.1.0     ether1-gateway       -------> Disabled this                 
 2 D x.x.x.x/32  x.x.x.x    pppoe-out1

Typically when an ADSL modem is placed in bridge mode it retains a private IP number which can still be used to access it. By placing a private number on the same subnet on your WAN Ethernet interface you should be able to contact it. e.g. if it retains 192.168.200.1/24 you could add 192.168.200.2/24 and be able to access it.

As regards it being in bridge mode - yes the routerboard is now your only security. See the following on securing the router itself and your internal networks:

http://wiki.mikrotik.com/wiki/Securing_New_RouterOs_Router

http://wiki.mikrotik.com/wiki/Manual:IP/Firewall/Filter