Using 2wire 3801HGV in conjunction with non-AT&T ISP

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Using 2wire 3801HGV in conjunction with non-AT&T ISP

I currently have tv only for U-Verse and internet through Cox (ATT can't compete pricewise or speedwise with what I have).

 

My current connections are:

 

ISP:

 

coax > modem (192.168.100.1) cat5E > router (192.168.1.1) > wired to multiple computers many with static IP's based off MAC's, DNLA devices and numerous wireless devices

 

AT&T:

 

line into green DSL port on 3801HGV > coax homePNA for 1 tv and LAN to 2nd tv

 

I am wanting to combine the two routers into one network because I want to use the wired LAN ports of the 3801 for some new items (it's in a different part of the house).

 

I've read the suggestions when using a current setup behind the 3801 but those all seem to pertain to those who are also using ATT for their internet.

 

I understand I obviously need to assign different ranges of local IP's and was going to set the 3801 to use the optional 172.16.0.0 starting point and also turn off the wireless feature. I assume using the 172.16.x.x sticks after a power outage? This would present me with the least amount of hassle dealing with all the current assigned IP's and port forwarding instead of changing my router to say 192.168.2.x range.

 

But my questions are: do I have to hook my incoming internet up from the current modem to the 3801 (I guess the ONT port?) instead of the current router's WAN port and then plug my router's WAN into one of the LAN's on the 3801. Or can I run a cable from one of my current routers LAN ports to the 3801 to give anything on that side internet access? Or can this simply not be done? If I can run from my current router's LAN port do I run to the ONT or LAN on the 3801 and does it need a crossover or "standard" CAT5E?

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Re: Using 2wire 3801HGV in conjunction with non-AT&T ISP

If your goal is to have additional ports, purchase a switch and run an Ethernet cable from the Cox router to the switch in the location that you desire.

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Teacher

Re: Using 2wire 3801HGV in conjunction with non-AT&T ISP

Actually the purpose is also so it's no longer necessary to switch networks on various devices that have the Uverse app installed on them to act as remotes for the Uverse tv receivers.

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Accepted by ATTDelia (Employee)
‎09-30-2015 1:39 AM

Re: Using 2wire 3801HGV in conjunction with non-AT&T ISP

The problem you're going to run into is that both your router and the 2Wire 3801 are both running DHCP. DHCP on the 2Wire 3801 cannot be turned off because the STB units require it.

With 2 DHCP servers running on the same network, any DHCP devices you have may not get their IP address and gateway from the correct device. For computers, this would cause then to attempt to use the Internet through the 2Wire router, which won't work. For your STBs, this may cause them to try to reach AT&T's video servers through the Cox connection, which also won't work.

The only viable way to do this would be to multihome the computers that need access to both networks, and have the networks physically separated with 2 NICs on those computers, or use VLANs with a single NIC and multiple virtual LAN connections. This would also require VLAN-capable switches.

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Teacher

Re: Using 2wire 3801HGV in conjunction with non-AT&T ISP

Thanks for the reply SomeJoe7777.

 

If I were to disable dhcp on the existing router where I can set static ip's, would that change my options?

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Accepted by topic author robin58
‎09-30-2015 1:39 AM

Re: Using 2wire 3801HGV in conjunction with non-AT&T ISP

[ Edited ]

If you completely disabled DHCP on the existing router and statically assigned everything, then yes, you could bridge the networks together LAN-to-LAN and it would work.

You would also either need to:

1. Use the same subnet for everything and ensure that your static IPs that you use don't overlap the DHCP range on the 2Wire.

or

2. Use different subnets, and multihome either the computer(s) needing to contact both routers, or place a secondary IP address from the 2Wire subnet on your router so that it will route packets on the same (LAN) interface.

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Teacher

Re: Using 2wire 3801HGV in conjunction with non-AT&T ISP

Thanks again for your reply. I'll play around with it tomorrow.

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