Choosing the right data-center interconnection (DCI) type can be difficult and requires proper planning in order to account for all business requirements and technical constraints. Let’s break down the most common DCI options offered by today’s service providers:
- E-LINE or E-LAN : MEF, the Metro Ethernet Forum is a standard body which specifies Carrier Ethernet and it’s services. They define E-LINE as a Point-to-Point (P2P) service and E-LAN as a Multipoint to Multipoint (M2M) service. E-LINE is most often associated with EoMPLS and E-LAN with VPLS.
- L3VPN: Also known as MPLS VPN, is well known in the industry as a Layer 3 virtualization technology. See my post on MPLS VPN for more details.
- Dark Fiber: Dark Fiber is a piece of a service providers optical fiber infrastructure that is not currently being used. The “Dark” in Dark Fiber generally means that the fiber has not been lit by the carrier and that it is entirely controlled by the customer.
- Internet: In the past few years, the internet has been often paired with different overlay technologies to interconnect data-centers. An iVPN (Internet VPN), commonly refers to the usage of a tunneling technology (like GRE) to transport data over the internet.
Here are some charts I’ve put together that compares different design requirements to these different DCI options.
From an enterprise perspective (as the customer):
From a carrier’s perspective (as the service provider).