MAC Encapsulated Routing

[xbipin]

just wanted to check if routertech firmware is capable of doing MAC Encapsulated Routing (MER) as ADSL broadband connections in India using reliance broadband use this rather than plain PPPoE or bridged connections and routers with MER only work, mostly the router provided by them only work for their connections

[thechief]

Sorry, but I have no idea what this is. I think your best way to find out is to try and see if it works.

[xbipin]

basically the provide in India named reliance use ADSL connections but its not just a standard pppoe connection but in the list there is something know as MER which is just pppoe conenction but only listed MACs on isp r allowed to connect so if set in plain pppoe and NAT on router then it wont work, the router needs to replace the MAC address on all packets such that all packets appear to be coming from the router only and nothing else, the isp does this to block using NAT and share a single line among multiple PCs.
i might not be clear on explaining but this link might explain more
http://www.dslreports.com/forum/remark,12695919

[thechief]

Well, this is all gobbledegook to me. However, if I understand correctly what is being said (and that is a very big "if"), it might be possible to achieve the desired result by using two routers - one for the WAN connection, the second one connected to one of the ports of the first one, to be used for the LAN.

If you don't already have two routers, I would not recommend buying another one just to test this (possibly fatally flawed) hypothesis.

[xbipin]

i tried all that but doesnt work coz if the main router is not set to MER then it just wont connect to ISP, regarding the NAT that can easily be solved using NAT softwares etc which is the least of my concerns.
main thing is the router needs to be in MER mode then only will it connect to server and in it u dont need to feed in any user id and pass coz as soon as connected, then if u try opening a site then due to captive portal at isp, u need to login into ur account then only u will be able to surf etc.
if this MER thingy can be added then there would be tons of guys wanting to flash their routers to routertech to be able to use any normal market dlink etc routers with reliance ADSL broadband.

[mstombs]

MAC addresses are only used on Ethernet segments, and nat routers work at IP level with the lower level arp protocol to resolve the IP/MAC pairing. All WAN traffic to/from a nat router is to/from its WAN IP, there are no LAN MACs to change, the nat router remembers which LAN IP is associated with each WAN connection using its nat translation tables.

PPPoE is really PPP over Ethernet over ADSL, sounds like your ISP wants to turn the ADSL device into a Ethernet bridge only using the Ethernet over ADSL bit. This is quite common with cable modems, means you need to use an Ethernet router as the single device connected to the ISPs modem.

It may be that the "dhcp" WAN connection does what you want, but you may need to change the WAN MAC address to that of your ISP supplied modem - this is seen in UK with BE/O2.

[xbipin]

now this seems to go over my head but ill explain how it works with the isp.

there is just one pair of wire coming to the home and the isp provides a ADSL modem with which when set to MER can connect to isp and the PC connected to the modem gets the WAN ip and if the modem is enabled with NAT then can work like a router but earlier isp wasnt allowing this as they used to lock the modem with a router but the technician gave away the password so i managed to enable NAT and connect multiple PCs on LAN segment and the modem does the NAT but the issue is the modem is just too weak to do NAT for many LAN PCs as i doubt even if it has 1MB of RAM so what happens is if state tables increase to just 100 or so then the modem starts dropping connections, now what i plan to do is replace this modem with a better ADSL router which is much stronger and with more RAM but the standard routers dont have this MER mode nor does routertech so with this no other modem or router is able to connect to isp.

[xbipin]

regarding the MAC address change to that of the isp supplied modem, thats no issue as the isp usually allows a MAC change over phone so i need to call them up and give them new MAC of new device and they will authorize it.

[xbipin]

simply changing the mac on a dlink flashed with routertech doesnt work untill the router is set to MER mode like the isp provided one.