EVPN to Managed AVPN Service Upgrade FAQs

Reuse of the access circuit and reuse of the router

1. Why is a POTS line (Plain Old Telephone Service) required?

Customer responsibilities include provisioning of an analog line (aka POTS – Plain Old Telephone Service).  This customer provided analog line allows AT&T to dial directly into the diagnostic modem which AT&T provides. 

The preferred option is for a dedicated analog line to be provisioned.  This allows AT&T 24 x 7 access in the event we detect a problem or need to complete a requested change to your service.  If there is a problem during the evening for example, AT&T can begin diagnostics and potentially correct the problem before business hours begin. 

2. What if no POTS line is available at my site and none can be ordered?

The migration to AVPN can still be completed without POTS.
However if no analog line is made available for out of band access, then AT&T’s resulting inability to remotely access the router may require site visits for work that could otherwise be done remotely and will delay diagnostics and trouble resolution. AT&T may charge a fee where a POTS line has not been provided and where additional site visits are required.

3. Is there a more modern alternative than POTS for out of band access to the router?

AT&T is working on alternative solutions – including wireless – for out of band access. Until these alternatives are rolled out globally, POTS remains the strategy for out of band access to the router.

4. Will there be downtime at any point during the upgrade?

The existing access circuit and router will remain in place. AT&T will request a 2.5 hour window to apply the AVPN configuration to the router. During this window, traffic classification (Class of Service – COS) will be impacted. There will be no actual downtime for your network. Given that COS will temporarily be disabled, congestion may occur if the migration is performed during peak hours. This could lead to slow throughput of your traffic flows until the situation is normalized. 

5. Which activities are performed during LAN migration?

A remote AT&T engineer will perform following activities:

  • Change BGP Filters from EVPN filters to AVPN filters
  • Remove EVPN router configuration
  • Apply AVPN router configuration
  • Apply AVPN Class of Service Profile
  • Make numerous Operations Support System database updates to change from EVPN to AVPN

The AT&T engineer will then perform testing.

The site contact will be asked to validate network performance after this.

6. Will IP addresses change when upgrading from EVPN to AVPN?

No. The EVPN IP addresses will be reused.

7. Will I receive a new VPN box?

No. The VPN box will be reused.

8. Will the assurance id change?

Yes. The AVPN assurance id will be different from the EVPN assurance id because naming conventions for both services are different.
AT&T will communicate the new assurance id to the site contact.

9. Will a portability order be required?

No. Assurance id will change automatically. It is however important that customers update all internal documentation with the new assurance id. As the router is being reused, it is highly recommended for the site contact to also manually change the assurance id on the router label.

10. Is there a rollback scenario in case the network does not come up on AVPN?

Yes. If at any point during LAN migration there is an issue, the remote AT&T engineer can perform a rollback to EVPN.
If issues occur after LAN migration they will be handled under the BAU incident process that starts with reporting the issue that you experience to SWIFT customer support.

11. How about the EVPN disconnect after migration is finalized?

No EVPN disconnect is required for sites where circuit and router is reused. Physical setup remains the same and the site will have been converted to AVPN in AT&T’s tooling.

12. Is there a link available to a full-version AVPN service guide?

Yes. Please click here: AVPN Service Guide

13. What if I want to postpone the upgrade to AVPN?

Customers are kindly requested to inform AT&T in case they are temporarily unable to have the upgrade performed, e.g. due to other ongoing or planned projects.
AT&T will then work with the customer to identify the best time to launch the AVPN order and complete the upgrade.
If customers plan to have the upgrade postponed until after 2018, they are requested to put in place a contingency plan to ensure connectivity to SWIFT as AT&T will be withdrawing the existing EVPN service and cannot guarantee EVPN connectivity after Q4 of 2018.

14. This is a logical change. Which actions are expected from the customer for this upgrade?

AT&T needs approval from the customer to launch an order for the migration. Customers will be asked to sign an order form.

Once signature is provided, AT&T will prepare, schedule and perform the change independently. No further customer action is required. Customers will receive confirmation after the change is complete.


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