Switch group or bridge ethernet ports on TA908e 2nd Gen?

[skirschplex]

I'd like to simplify our CPE devices where we have deployed AdTrans' for customers.  We are an ISP and typically set up the Adtrans as a 'WAN' devices on our private network and vlans.  Several other much simpler SIP devices we use (like the Cisco SPA122) have two bridge ethernet ports to start with, allowing you to install them as a WAN device and passthrough to the customer's router.  I only have a few AdTrans out in the wild now and mostly they went in places where we already had a WAN switch (for the most part we're using Mikrotik CRS switches with two SFPs and a handful of ethernet ports or Mikrotik 2011s with one SFP).  We're starting to rely on the AdTran platform more readily for commercial work however and I have yet to figure out if the two ethernet ports can be bridged together.  They don't appear to be part of any sort of switch group by default.  Any help would be appreciated!

[Anonymous]

What exactly is your application?

-Mark

[skirschplex]

We're typically doing SIP -> FXS or SIP -> PRI. I'm trying to avoid

NAT, trying to avoid having these behind customer's routers where I have

to make special requests for access. We like to keep all phone devices

on the customer's WAN side so we can have full control and access.

I'm simply trying to figure out if I can use the two ethernet ports as a

'passthrough' port. I can plug the WAN connection into Eth 0/1, the

customer's router into Eth 0/2, be able to access the management IP for

the AdTran through the WAN port, etc. I don't really want the AdTran to

handle anything like DHCP, acting as a gateway for a static IP on Eth

0/2 or having special routing. I just want the ports bridged together.

[Anonymous]

Yes, there is no way to bridge the two Eth ports in the ADTRAN. We are not designed for that application. That box was designed to sit on the edge and terminate WAN connections and act as firewall/router.

Only way to get that to work in your application is to have an extra Public /30 subnet between the 900 and the customer’s router, to keep it all public and we would route between the two networks without having to NAT. Kinda like a DMZ to the router.

Let us know if you need anything else.

-Mark

[Anonymous]

Hi Mark,

Please provide some sample configuration, or link to existing documentation regarding WAN passthrough. I've often run into these two scenarios and am not sure the "right" way to handle them:

Using a TA908e at the WAN edge for PRI or analog handoff. Customer only has a single /29, with the TA908e eth 0/1 connected to the ISP, and would like to use the remaining addresses on their data firewall connected to eth 0/2.

Using a NV3448 at the WAN edge for managing hosted PBX registered endpoints. Customer only has a single /29 and would like to pass through the remaining addresses, only this time we have more options using switchports for a WAN vlan, BVI, or just eth 0/1 and 0/2.

In both scenarios the AdTran's job is to play traffic cop and preserve call quality over the connected data firewall.

[jayh]

The TA900s unfortunately don't do bridging. The best scenario for this is to use a separate subnet for the point-to-point link from your provider edge router to the TA900, then route the /29 to it.

Adtran does support a /31 subnet mask on point-to-point links per RFC 3021 so you'll only have to burn two IPs per customer to do this.