Is Telia (AS1299) a tier1 network?

Lots of networks claim to be tier1 providers on the Internet today, Telia is among them. Wikipedia agrees with that, though as always with Wikipedia, it's not a primary source of information and so that page can easily be manipulated. During some recent network troubleshooting I looked into a few of their relations and found "evidence" pointing in another direction...

Given that the tag "tier1" is generally something positive in marketing, I can imagine quite a few networks who want to name themselves tier1 to look good for potential customers. Now, just finding a definition of what a tier1 network really is can be quite hard (as witnessed on the Wikipedia page), but I'm gonna go with "not paying settlement fees to any other network for reaching prefixes". Of course, with fiber swaps or whatever, this can easily be circumvented.

As mentioned, Telia do claim to be a tier1 provider and they do claim to be so according to "my" definition. However, I've found discrepancies.

Looking at lg.telia.net we can see that routes that Telia receive from peers are generally set to a local-pref of 150. For all relations that I know of to be true peer relations, this is true.

24.51.192.0/20     *[BGP/170] 4d 06:01:23, MED 0, localpref 150, from 213.248.80.247
                      AS path: 2828 I
                      to 80.91.247.172 via xe-1/1/0.0


4.0.0.0/9          *[BGP/170] 30w4d 09:57:35, MED 0, localpref 150
                      AS path: 3356 I


11.2.0.0/16        *[BGP/170] 4w6d 14:25:56, MED 0, localpref 150, from 213.248.80.247
                      AS path: 3549 I

While looking at prefixes from AS701, we see that they have a localpref of 100. Telia doesn't want to send traffic over these links whenever they can avoid it and this could indicate that they do not have a true peer relation but rather that Telia is paying Verizon to transit traffic.

2.2.2.0/24         *[BGP/170] 2d 21:14:43, MED 0, localpref 100, from 213.248.80.247
                      AS path: 701 I

Another tell tale sign of peering vs customer relationship is which routers the networks interconnect. Larger networks generally have dedicated routers for peering and other dedicated routers for customers. Let's see how it looks in between Telia and Verizon.

A traceroute from Telias core router in Atlanta to 2.2.2.2 (which is a host within AS701) looks like this:

traceroute to 2.2.2.2 (2.2.2.2), 30 hops max, 40 byte packets
 1  ash-bb1-link.telia.net (80.91.246.76)  14.117 ms ash-bb1-link.telia.net (80.91.251.85)  13.956 ms ash-bb1-link.telia.net (80.91.252.121)  12.680 ms
 2  GigabitEthernet2-0-0.GW8.IAD8.ALTER.NET (63.65.76.189)  20.568 ms TenGigE0-2-0-0.GW1.IAD8.ALTER.NET (63.125.125.41)  14.871 ms GigabitEthernet2-0-0.GW8.IAD8.ALTER.NET (63.65.76.189)  15.520 ms
 3  0.xe-3-1-1.XL3.IAD8.ALTER.NET (152.63.35.142) [AS  701]  15.401 ms  12.727 ms  14.009 ms
 4  0.so-3-2-0.XL3.NYC4.ALTER.NET (152.63.0.182) [AS  701]  21.847 ms  21.765 ms  20.496 ms
 5  POS6-0.GW14.NYC4.ALTER.NET (152.63.26.245) [AS  701]  21.076 ms *  24.231 ms

Here we can see that the first router we encounter on our way to AS701 is GW8.IAD8.ALTER.NET. What kind of box is that? Well it's easy to compare to the relations we know to be of a certain kind. For example, we know that Sprint peers with Verizon and so we can see what kind of a box a peer should be connected to in Verizons network to be considered a peer.

Sprint Source Region: Anaheim, CA (sl-gw31-ana)
IP Destination: 2.2.2.2
Performing: ICMP Traceroute

Tracing the route to 2.2.2.2
  1 sl-crs2-ana-0-14-2-0.sprintlink.net (144.232.11.11) 4 msec 0 msec 0 msec
  2 sl-st30-la-0-8-0-0.sprintlink.net (144.232.19.227) 0 msec 0 msec 0 msec
  3 0.xe-11-2-0.BR1.LAX15.ALTER.NET (204.255.168.93) [AS 701] 4 msec 0 msec 0 msec
  4 0.ge-2-1-0.XL3.LAX15.ALTER.NET (152.63.115.89) [AS 701] 4 msec 0 msec 4 msec
  5 0.xe-6-1-0.XL3.NYC4.ALTER.NET (152.63.3.105) [AS 701] 72 msec
    0.so-3-2-0.XL3.NYC4.ALTER.NET (152.63.0.182) [AS 701] 72 msec 72 msec
  6 POS6-0.GW14.NYC4.ALTER.NET (152.63.26.245) [AS 701] 76 msec *  76 msec

Here the first hop in Verizons network is BR1.LAX15.ALTER.NET. So, BR vs GW. I'm ready to say that Telia is connected to what Verizon would call a customer router (GW router), ie Telia is a paying customer.

To further solidify this, we look at a few more examples. Let's take France Telecom, which is known to be a customer of AS701 and see where they are connected.

traceroute to 2.2.2.2 (2.2.2.2), 30 hops max, 40 byte packets
 1  tengige0-10-0-2.pastr1.Paris.opentransit.net (193.251.242.141)  1.421 ms tengige1-3-1-0.pastr1.Paris.opentransit.net (193.251.132.237)  0.856 ms tengige1-6-1-0.pastr1.Paris.opentransit.net (193.251.132.249)  0.838 ms
 2  so-0-0-0-0.ashtr1.Ashburn.opentransit.net (193.251.242.98)  82.243 ms  79.668 ms  81.285 ms
 3  GigabitEtherne0-0-0.GW8.IAD8.ALTER.NET (63.66.38.33)  143.737 ms  142.902 ms  137.219 ms
 4  0.ge-4-2-0.XL3.IAD8.ALTER.NET (152.63.33.14)  138.384 ms  156.472 ms  141.338 ms
 5  0.so-3-2-0.XL3.NYC4.ALTER.NET (152.63.0.182)  164.409 ms  133.876 ms  135.295 ms
 6  POS6-0.GW14.NYC4.ALTER.NET (152.63.26.245)  275.507 ms *  180.504 ms

So, GW indeed looks like a customer type router. Let's do one more peer to be certain. Verizon do peer with Level3 and so we take a look from Level3s looking glass.

Traceroute from Baltimore, MD -

  1 ge-6-15-24.car2.Philadelphia1.Level3.net (4.69.135.121) 60 msec 232 msec 60 msec
  2 ae-6-6.ebr1.NewYork1.Level3.net (4.69.133.170) 24 msec 28 msec 24 msec
  3 ae-4-4.ebr1.NewYork2.Level3.net (4.69.141.18) 28 msec 28 msec 24 msec
  4 ae-1-51.edge2.NewYork2.Level3.net (4.69.138.195) 28 msec 24 msec 28 msec
  5 4.68.111.138 28 msec
    mci-level3-xe.newyork2.Level3.net (4.68.110.234) 28 msec
    0.xe-1-0-0.BR2.NYC4.ALTER.NET (204.255.173.53) [AS701 {ALTERNET}] 24 msec
  6 0.ae2.XL4.NYC4.ALTER.NET (152.63.3.117) [AS701 {ALTERNET}] 28 msec 24 msec
    0.ae3.XL3.NYC4.ALTER.NET (152.63.16.182) [AS701 {ALTERNET}] 28 msec
  7 POS6-0.GW14.NYC4.ALTER.NET (152.63.26.245) [AS701 {ALTERNET}] 84 msec *  32 msec

Here we see traffic being load balanced over what appears to be three separate links and two of the IP networks used are being provided by Level3, but the third, clearly resolves to BR2.NYC4.ALTER.NET, ie another BR router which shows that Level3 is a proper peer of Verizon.

As a side note, it is interesting that most of the link networks between Level3 and Verizon seems to be provided by Level3. As is customary, the IP network is usually provided by the party who also paid for the interconnect fibre. It seems that Level3 have paid for most of the interconnects with Verizon. The exception being when they have multiple links in between two routers, then we can see Verizon addresses popping up. This is most likely due to Verizon being somewhat unwilling to peer and Level3 offered to pay for most of the costs involved in establishing peering.

One could ask why I simply not look in BGP to find this information out. I did not because BGP is simply not accurate for determining this. Telia is most likely a customer of Verizon, but they are also quite likely tagging all of their prefixes with some BGP control community as to limit it's announcement from Verizons network to only Verizons other customers, thus appearing like a true peer.

but the traceroute knows better ;)

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