Thanks for the response Eric. I'm glad you touched on the E-LAN type services because I thought that a multi-point option over L2VPN could be an offer. It seems the VLAN PtP options give me more control on traffic engineering. For the PtP, "two VLAN" scenario that you spelled out, is that treated as two distinct circuits at twice the cost of one circuit or do you ever have carriers discount that a bit? I expect to pay "something" for the redundancy, but I don't need twice the bandwidth on the "Enhanced" NNI to the site. I also wonder if the site bandwidth would count towards the utilization commitment required on the tail NNIs.Do you know how that is treated? Thanks again! Mark On Fri, Jan 16, 2026 at 7:43 AM Eric C. Miller <eric@ericheather.com> wrote:
Every carrier calls it something different, but it boils down to a VLAN on the carrier's port that takes you PtP to another site. For example:
Dallas datacenter has a NNI with Provider. On that NNI, you've been given VLAN 101 that PtPs to Site. Atlanta datacenter has a NNI with Provider. On that NNI, you've been given VLAN 201 that PtPs to Site.
Site has an "Enhanced" UNI where Provider has given you 2 VLANs. VLAN 101 is PtP to Dallas, VLAN 201 is PtP to Atlanta.
Some MEF-head will surely correct the terminology here, but having worked with just about every national carrier, they all use the terms in different ways.
...Or, you can buy an E-LAN type service that is any-to-any and then do your own network over top of it. Most problems I've had with E-LANs revolve around spanning-tree (make sure your edge devices aren't sending BPDUs into the E-LAN) or the provider VPLS locking up where certain endpoints can't be seen from other endpoints. Be prepared to recover your network using hairpin routing from a couple of sites while the provider resets everything.
Eric ------------------------------ *From:* Mark Blackford via NANOG <nanog@lists.nanog.org> *Sent:* Friday, January 16, 2026 8:33 AM *To:* North American Network Operators Group <nanog@lists.nanog.org> *Cc:* Mark Blackford <mblackf@gmail.com> *Subject:* Exploring EVPL / NNI redundancy options
Does anyone have experience implementing redundancy on their EVPL services within the same carrier? For instance, I have many point-to-point scenarios using EVPL providers to connect sites to Dallas. I’m looking to add a new pop in Atlanta this year for expansion and redundancy.
It seems possible to have a “Site A” with a current drop off NNI in Dallas added to the new POP on Atlanta within the same carrier network for data center redundancy, but I am not sure how practical that is in terms of cost and implementation. Latency would vary of course, and I am assuming they give you a different VLAN (but maybe not?).
I welcome any comments like if this is a good idea or not, what carriers I should consider, and experience with cost.
Thanks in advance!
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