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faraway's profile

Voyager

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3 Messages

Sunday, March 3rd, 2013 11:42 PM

Advanced UVerse setup -- need help

Hello!

 

I've got Uverse TV service (via a 3800GHV-B router), and I'm thinking about adding UVerse Internet Service too.  However, I am worried.  I need to keep my current router, a Linksys, due to a highly specialized network setup that the 3800 cannot manage. 

 

From what I am reading, I would need to put the Linksys in a DMZ and allow it to handle all firewall, wireless and routing functions for my computers.  My concern is that that this would also force the Linksys to handle traffic meant for the DVR.  I really just want to have the 2WIRE play traffic cop: send all IPTV traffic to the DVR and send everything else to the Linksys.  I am diagramming what I am trying to do here

 

Is this possible?

 

Thanks for your help!

 

 

Accepted Solution

Official Solution

ACE - Expert

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34.7K Messages

11 years ago

No, your router need not (and should not) be involved in the IPTV traffic.  Most consumer routers can't handle multicast and IGMP v3 protocol correctly.

 

You can plug your router into one port of the 380x, and keep all your network behind it.  I'd suggest reading post 2 in this thread.

 

Voyager

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3 Messages

11 years ago

Awesome response and reference Jeffer -- thanks a bunch!

 

My router will actually handle multicast and IGMP, which was my concern.  I have a lot of devices on my network, and in the past, allowing multicast has resulted in a strained router, strained NICs, constant firewall alerts and impossibly cluttered logs & captures.

 

I have one more question for you that's kind of theoretical -- you seem very educated on networking, and I do not have proper network education.  I'd like to avail myself of your knowledge while you're here.  Assuming I wanted to put everything behind the Linkys, including the DVR, would putting the DVR in its own VLAN while separating everything else into another prevent the scenario I described in the second paragraph?  

 

 

ACE - Expert

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34.7K Messages

11 years ago


@faraway wrote:

Awesome response and reference Jeffer -- thanks a bunch!

 

My router will actually handle multicast and IGMP, which was my concern.  I have a lot of devices on my network, and in the past, allowing multicast has resulted in a strained router, strained NICs, constant firewall alerts and impossibly cluttered logs & captures.

 

I have one more question for you that's kind of theoretical -- you seem very educated on networking, and I do not have proper network education.  I'd like to avail myself of your knowledge while you're here.  Assuming I wanted to put everything behind the Linkys, including the DVR, would putting the DVR in its own VLAN while separating everything else into another prevent the scenario I described in the second paragraph?  

 

 


I'm not sure what the capabilities of your Linksys are.  If it has the capability to create a VLAN between two or more ports and you connect one of those ports to an RG (3801) port and the other to the DVR (assuming you don't have any other STBs connected to a non VLAN port), that should work and not flood the other ports with traffic.

 

OTOH, if your router fully implements IGMP v3, then it should isolate the IPTV traffic to the DVR anyway.  I'm assuming you intend to connect a WAN port on the router to a port on the RG?

 

 

 

 

Expert

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9.4K Messages

11 years ago

Be careful with terminology and purpose here, because you can quite easily talk yourself into something that won't work and doesn't make sense.

 

First, keep in mind what layer of the OSI model that each of these functions are talking about.  Layer 2 (switching) functions are completely separate from layer 3 (routing) functions.

 

The AT&T 2Wire residential gateways have the DMZPlus mode for user convenience.  The DMZPlus mode already separates IPTV traffic and user Internet traffic at layer 3.  This means that your router will get the public outside IP address, but the DVR and STB units will still get 192.168.x.x addresses from the 2Wire.  They are therefore on a separate subnet, separated from your computer traffic at layer 3 (routing/IP).

 

VLANs and IGMP snooping are layer 2 functions that occur at the switching level.  These functions need to be used to separate traffic at layer 2, e.g. when the IPTV traffic and Internet traffic that you want to keep separate would otherwise share a switch or share an Ethernet segment.

 

If your goal is to make sure that the IPTV's multicast traffic does not interfere at all with your Internet traffic destined for your Linksys in the DMZ, no additional configuration is necessary because the RG, in addition to implementing layer 3 separation as described above, also implements layer 2 separation via IGMP snooping at it's built-in 4-port switch.

 

So, to configure this like you want, plug your Linksys directly into a port on the RG, and configure it as the DMZPlus device using post 2 in the thread that Jeffer referred you to.  Then plug the DVR and STBs into other Ethernet ports on the RG.  Layer 3 separation ensures that they will be on a different IP subnet than your Linksys and it's LAN computers, and layer 2 separation ensures that the IPTV multicast traffic will not be present at the WAN port of the Linksys.  No further configuration of IP multicast, IGMP snooping, or VLANs is necessary in your Linksys.

 

Voyager

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3 Messages

11 years ago

Thanks a lot for taking time to not only answer, but explain guys; I wanted to know not only how to achieve my goal, but to satisfy my curiosity about how the traffic is routed.

 

+Reps for all! 🙂

Teacher

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52 Messages

10 years ago

You mean like this one which is one of 3 on my home network? This router of mine handles IPTV traffic. Screenshots_2014-04-21-00-03-07.png

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