Re: Sagemcom Gateway F@ST 3864OP Bridge Mode


I am reading that message as being that you have to plug the Sagemcom modem in first in order for the ADSL connection to be fully setup (perhaps because Optus only fully provision the service if they see a sagemcom modem on the other end). but once that has been done then you can remove the crappy Sagemcom modem and replace it with any good ADSL (but preferably VDSL) modem of your choice. The only hassle is that the Optus VOIP home line will not work with another brand of modem due to Optus's policy of frustrating customers. If you don't want the home VOIP phone then just replace the router with a real router and you're good to go.

Just a note that a VDSL modem will also connect using ADSL and ADSL/2+ as well as allowing connection to the NBN when you get that (so you won't have to buy yet another modem) but an ADSL/2+ only modem will not be suitable for the NBN.

Re: Sagemcom Gateway F@ST 3864OP Bridge Mode


hi, thanks for the answer.I read your answer and few other posts on internet. and I come up with this solution. In my case, i don't need the voip phone line. And i want a good quality router that has advanced wifi speed and features like QoS so i can limit bandwith on other users .Basically, i throw away the optus sagecom , and then get a proper modem that works for adsl ,or  vdsl if i want to future proof for nbn , then a good router that suits my requirenments.However i read up on internet about something called 'switch' along the lines of modem and router. Do I need that or I am gud to go with a modem and a router in my case?

Re: Sagemcom Gateway F@ST 3864OP Bridge Mode


Use the DMZ, see this link for example how to set up Google Wifi and retail phone via Sagemcom.

Re: Sagemcom Gateway F@ST 3864OP Bridge Mode


“If you're not planning on using the landline, all you do is take the ethernet cable from the NBNco box to your existing router - you don't actually need the Optus Router (which is a locked down, crippled piece of garbage, as opposed to the open-ish hardware optus used to provide).”


The NBN man brought the little NBN Gateway and was in ‘n’ out in five minutes flat. All he did was connect the device to the cable plate turn it on and about one hour later the connection appeared to be active.


In my ignorance I removed and replaced my Telstra cable modem with The Optus Sagemcom but I ended up with a “double NAT” when I plugged it into the Apple AirPort Extreme router.


Your solution is brilliant as removing the Optus Sagemcom from the equation did two things for me: 1) Eliminated cable clutter and 2) resolved the double NAT issue.


I am not happy about paying for an Optus Sagemcom I’m not even using. 


There should be a slightly cheaper plan minus the modem.


It is wasteful sending me modem that will end up in the recycling before it’s time.

Re: Sagemcom Gateway F@ST 3864OP Bridge Mode


Optus Support eventually put me through to Sagemcom for hardware support.


After describing my issue, they noted my details and was advised they’d call me back.


Ten hours later and I await a response. Perhaps tomorrow.


Re: Sagemcom Gateway F@ST 3864OP Bridge Mode


OMG you are a star!!! I have spent so many wasted hours trying to get my modem to 'bridge'. Your detailed post has been a godsend. And I cannot believe the speeds I am getting through my Netgear D6300 (yes an older modem these days but jeez, leaves Sagem for dead. EVERYTHING works using your instructions. Thank you sooo much!


I still cannot believe how in the age of this dodo called NBN that Optus can provide such a useless and unreliable modem in the name of 'securing their network' and not providing the VOIP protocols. Very uncompetitive, something the ACCC should look at. I don't have time to raise with them...


Thanks again! OMG it works at last!

Re: Sagemcom Gateway F@ST 3864OP Bridge Mode


as far as I can see ICMP is always turned on in the sagemcom modems.

I can ping both the LAN address and the WAN address of the modem/router and I get replies both ways.

So, to test the LAN port I goto a command prompt on my windows PC and type ...
as that it the LAN address I've set for the modem rather than the usual or (or as Telstra does

I get normal replies back


Microsoft Windows [Version 10.0.17134.285]
(c) 2018 Microsoft Corporation. All rights reserved.


Pinging with 32 bytes of data:
Reply from bytes=32 time<1ms TTL=64
Reply from bytes=32 time<1ms TTL=64
Reply from bytes=32 time<1ms TTL=64
Reply from bytes=32 time<1ms TTL=64

Ping statistics for
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 0ms, Maximum = 0ms, Average = 0ms


On my tablet I can do a similar thing using the Android PING app to the WAN address of the modem (if I turn OFF WIFI on the tablet and reply on the SIM card for internet.

Re: Sagemcom Gateway F@ST 3864OP Bridge Mode


I'm trying to follow the guide on page 2 of this post but when I get to the 'Add Entries' part (Advanced Setup / LAN then ENABLE DHCP SERVER and click on ADD ENTRIES), it just brings up a blank page with nowhere to enter any information. Is this new thing that Optus have done or am I doing something wrong?

Re: Sagemcom Gateway F@ST 3864OP Bridge Mode

that feature is also disabled. along with many other features. I totally regret signing up with optus NBN. So much headache and the extra money you have to flop out. I will make sure others won't face the same problems like we did.

Re: Sagemcom Gateway F@ST 3864OP Bridge Mode


It's true it's disabled, but you don't actually need to do that. Just set the IP range for the start of DHCP up at .20, say, and your .2 allocation for you real router will be untouched. Then you can still use the Sagemcom dhcp for wifi (or any of the 3 spare lan ports) and statically assign the .2 address in your router setup.


I did notice, however, that I was getting nowhere near the full upload speed this way. Connected directly I got close to the 100/40 max, but via my real router in the sagemcom DMZ I only get 100/15 at most.

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