OT:WAN Backbone and Internet in DC

Hi all

In my customer data centre network, we have primary as well as Disaster
Recovery site and we have Inter DC links which is the so-called WAN
Backbone. And we have Internet connectivity from my Edge routers on both
the Data centers sites to upstream Internet Service Providers
I dont understand what is the difference between the WAN Backbone and
Internet in terminologies in documentations.

THis is what my understanding is WAN Backbone is nothing but ur Data centre
Interconnect technology that u r going inorder to reach other DC site in
case any links to upstream Providers got lost or else any other issue
making the traffic.

Why do they call as WAN Backbone? Its just a normal DC Interconnect
technology where we can use another Service Provider just like a VPN
connection to reach another site. I probably feel WAN Backbone used in ISP
Core network where they have large mesh of LSPs to each and every Edge
devices.

Whereas the original connection from the Edge routers to the upstream ISPs
are exclusively for the internet routes and not for any DCI or VPN traffic
from one DC to another DC

In this case when designing the DC sites, we need to have two separate
service providers . One for the Internet Routes and another for the DC
interconnect

On what scenarios does the Inter DC links will be used and in what purpose
it is required ?

I see there are lot of solutions for DC Interconnect ranging from VPLS to
Layer 3 VPNs over the internet or else plain Layer 3 routing. Which works
best and i see the "It depends" answer coming !! :)

Can someone throw light on this more.

-- 
Regards
Routing Freak
CCIE#35889 (SPv3)
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