If your ASUS is anything like this model :-
Asus DSL-N55U - 300 Mbps Dual Band Wireless N Router ADSL 2/2+ Modem
Then the answer is unfortunately not as a direct replacement, that is an ADSL modem, for fibre you need a VDSL modem. Plus the TT supplied router will be customised for the Youview service (if you have that).
Can't comment on the TT fibre router as fibre is still a distant (but getting closer) dream where I live.
There are ways to set up your TT and Asus in a master-slave type combination, this is sometimes used to extend the wireless range of configurations.
There is a knowledge base article on this - hopefully giving an answer, but I've never had to try this, so no idea how practical and or successful this is.
You can use your Asus DSL-N55U with the Fibre Modem (which is exactly what I have and have done) Just set your new SuperRouter into Bridge mode, and change the connection (WAN in Asus) to Dynamic...
Screenshot of Asus WAN Setup Page:
Hi mate, that's me got my super router.
I'm some what of a networking noob, so I'm having a bit of trouble getting my setup up to work? Do you mind giving me a more basic step by step? Would be hugely appreciated if you could!
Just as a first example im not even sure how to set my super router into bridged mode
OK. You need to login to the superrouter, Click the INTERNET tab at the top then select Internet Connection on the left Side
Then, Click Edit and change the Conenction Type to Bridged. Untick the TR069 box. Then SAVE.
Then, Click on HOME NETWORK TAb at the top.
Click on LAN Interface on the left Menu and then click the "DHCP Server" Section to open the dropdown.
UNCHECK the Enable DHCP Server option and SAVE
Then. Connect your DSL-N55U to the SuperRouter using a network cable. Go to the Admin Page of the DSL-N55u and select WAN button the left side. Change the connection type to Automatic IP as per the original piccie.
Sorry....! Just seen that the super router is incorrect.
You are on fibre yes? Looks like you have it set to Adsl ather than vdsl. Your screen should look like the one in the link instructions above.
Best option is a factory reset then try again.
Factory reset the super router and then try again.
I've disabled the DHCP server and the asus port is definitely correct.
My fibre hasn't been activated yet, I thought I would get all this setup so that when the fibre goes live I'll be ready.
Am I best just to wait until they've activated the fibre then try again?
Again, thanks for all your help