Bypassing the SIP ALG on new firmware ATT U-Verse 2Wire Modems
Jul
12
2010
Bypassing the SIP ALG on new firmware ATT U-Verse 2Wire Modems Comments: 13
A new version of firmware is being pushed to ATT U-verse 2Wire modems that turns on the SIP ALG and prevents users from accessing the advanced tab to turn it off. Currently the only remedy is to have the modem placed in bridge mode and add a router, such as the Linksys WRT54G, which does not have a SIP ALG.
Here are a few external links to help you along with this process:
SIP ALG 2Wire
This is becoming a huge issue for us.
I work for a VoIP telephone service provider.
My question on this solution is how will this effect U-verse TV?
ATT is no help..
U-verse TV
For our customers it hasn't been an issue as they've been using U-verse as a stand-alone product.
Personally, with Verizon FIOS I still have the original Verizon FIOS router in my network in bridge mode and it feeds the coax network, but my main router is a DD-WRT router.
Internet => DD-WRT => Verizon FIOS Router => Coax
I have my LAN and my WiFI network also hanging off the DD-WRT router.
So, some setup like that may work well:
Internet => Router => AT&T Router => coax
But hang your LAN and phones off the Router directly, not connected at all to the AT&T Router.
If you have any luck, let us know.
$1000 bounty
Been working on this for days with ATT.
ATT U-Verse Tier2 technician told me that the cable will not work if the router is bridged.
So I told them I am offering a $1000 reward to any ATT Rep that can tell me how to turn off the SIP ALG in this new firmware on the 2wire. They have escalated my issue there but I have had no takers so far.
Internet => Router => AT&T Router => coax
Unfortunately this setup will not work with U-Verse because the 2wire is a DSL modem/router. The connection is RJ-11 and not RJ-45. This means that the 2wire MUST be the first device in the circuit in order to connect on the DSL line.
See image: http://www.lotusgeek.com/LotusGeek/LotusGeekBlog.nsf/Images/ROLR-7SXN53/$File/2Wire-3800HGV-B_back.jpg
I wish they had Fios!!!
Don't understand your
Don't understand your comment re: "the cable will not work if the router is bridged".... do you mean the TV services?
Does someone else know: If you put your UVerse 2Wire into "bridge mode" as described in this post, how does that affect your TV devices and your phone ports?
U-Verse and SIP
I assume you had a frmware upgrade to something like version 6.1.9.24-enh.tm
Put your adaptor in a DMZ.
If you go to Settings/Firewall/Applications, Pinholes, and DMZ, towards the bottom you can "Add a new user defined application."
This is where you can define a group of ranges for ports that you want forwarded to a particular machine. One of the options on the "Application Type" drop-down is "SIP Telephony". That is a new option that wasn't there before on the corresponding 5.x pages. Once you've defined it, you can go back to the previous page and assign it to your TA.
Cheers
U-verse dropping SIP packets?
I just started experiencing significant packet loss on my SIP trunk to the point that calls are almost inaudible. I was using g.711 and it sounded really bad, I changed to g.729 and now it's just bad. This just started yesterday evening and there have been no changes on my network.
Any thoughts?
Thanks!
U-verse dropping SIP packets?
I discovered it was a problem at my SIP provider. Changed to a different proxy and all is better.
U-Verse, SIP ALG, and DMZ
OK. I've just spent two hours on the phone talking to about 20 people at AT&T. I have a 3800HGV-B router and they tell me that it cannot do "bridge mode". I also learned that a newer router they offer also does not have a "bridge mode". They tell me that all new ISP routers have no bridge mode functionality, that all the software is going to that design.
If I go through all the effort of connecting only a router to the back of the 3800 and setting that one "device" in DMZ mode, thereby issuing all IPs through my approved OnSIP router, will that let my MoH work or will the 3800 still be filtering and rebuilding SIP headers?
UVerse routing
Matt-
I'd be very surprised if that was true. I had another customer put their AT&T 2-Wire modem/router into bridge mode last week. Sounds like a tech spouting the company line on the future functionality of all modem/routers in the future. I find if I get an answer that does't make sense from one call-taker, I keep trying and find one who does really know what's up and takes care of the issue. Or I ask to be escalated or to talk to a supervisor.
If the SIP ALG is still on, it's still going to affect all packets- I'm not sure if the DMZ will bypass that. Also have to make sure you're not setting up 2 NAT's in doing this, as it will cause a larger issue.
Please don't hesitate to call us at the support line with any questions.
2wire bridge mode
If your 2Wire is not listing a computer with a static IP address, or you would like the 2Wire to act as a bridged router, the 2Wire offer the technicians pages to change advanced settings:
h t t p://{router ip}//tech/configuration.html
This will bring you into the advanced configuration for the 2Wire. If you have a server with a static IP, and the 2Wire does not have it listed, it will not forward network/internet traffic to that computer. You can reset your local area network’s computer list. This will force the 2Wire to start rebuilding the list again and re-detect your server.
This this problem become common, consider placing the 2Wire into bridge mode and using your own router. This will require a static IP.
Shawn Zernik
http://www.internetworkconsulting.ne
Bypassing the SIP ALG on new firmware ATT U-Verse 2Wire Modems
The AT&T 2Wire modems with the latest updates do not allow you to put the 2Wire into bridge mode. I have been able to get SIP working in the following way:
- Disconnect all devices that are plugged into the 2Wire
- Disable wireless on the 2Wire
- Connect the WAN port of a WRT device (I am using WRT600n) to the 2Wire
- Configure the 2Wire firewall and put the WRT device in DMZ
- Connect all wired devices to the WRT
- Configure the wireless on the WRT and connect wireless device to this wireless network
- Configure NAT/QoS --> Port Forwarding on the WRT and setup the correct SIP ports and IP addresses of your SIP router
Hope this helps!
IP Phone
The DMZplus mode works with SIP Devices. I pointed it to an IP phone (which registers to the customers PBX Public IP) behind an AT&T U-Verse 3801HGV gateway with 6.3 firmware.
That does the trick!
Thank you for posting this Justin, works like a charm! I was struggling with accessing my voicemail box from my IP phone - dialing *98 or the extension for the box did not work - it would just sit quietly. However, everything else worked including dialing other voice extensions. Very strange.