Router or Switch on a link towards a DC

Hello Redditors,

Basically this is the situation, we're about to get a circuit towards a new data center from the data center we're currently in. We want to be in this new DC not to put servers in there we just want to be able to BGP peer with 1 - 2 carriers that are in there directly.

So here comes the question, we've got to put either a router or a switch in that DC and terminate the circuit in there, and those carriers would then xconnect to this router or switch. The thing is, we've not decided which one we should get.

First, if we go with the switch route, we would terminate each carrier in a VLAN and then peer directly with our edge-router located in main DC, we'd use this L2 circuit as a trunk basically.

If we go with the router, then we would make those carriers peer with this device and then a route back towards our main DC.

So the debate is due to the pros and cons, if we go with the switch:

• Would in theory be cheaper (regular L2 switch only)
• We keep things as they currently are, keeping the peerings in our already designated edge
• less configuration to maintain (the switch would be kind of fire-and-forget)
• plenty of ports so we can keep adding peering links if we wanted (not that it'll happen in the near future)
• However there's the concern related to QoS, on the router would be easier to do this (mainly priority to control traffic in case links saturates)

If we go with the router

• Would have better QoS
• We would have a direct view of that DC, in the sense, if the transport link fails, we can use the public peering IPs to tshoot from that side as well (this wouldn't be possible with the switch, since it'd have a private IP only visible from our main DC)
• Would have more config to do, although I hate L2, so I'm ok with this (rather everything routed)
• Carriers would peer directly with this router, this allows us to tshoot peering from the perspective of the direct connection (and offload our current edge from applying policies, filtering, etc. Although current edge can work with this easily)
• We could do filtering directly in there so we optimize the use of the link towards of our main DC, if we were to filter in main DC the bandwidth of that link would still be used
• Would be more expensive since we'd need a router BGP capable full tables

This is a debate I currently have, if you were in this position what would you do?