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E-VPN and PBB-EVPN Take Data Center Interconnect to the Next Level

Tina-lamBy Tina Lam, Product Manager

MPLS based Layer 2 VPN has been around for over 10 years since the inception of IETF Pseuduowire Edge to Edge (PWE3) Working Group. Many drafts and standards have been added, since then, to address different applications and to improve scale and convergence in different topologies. L2VPN as a whole is widely deployed in both service providers and enterprises, from Ethernet services, to fixed and mobile convergence, to enterprise campus layer-2 transport.

Recently, one emerging driver that has been picking up a lot of momentum is to use L2VPN for Data Center Interconnect (DCI). Data centers are often situated in different locations, to be geo-redundant for the purpose of workload mobility and business continuity. At the same time the physical location of the data center has to be transparent to users and to applications. Hence the need for layer-2 connectivity between sites. While Ethernet over MPLS (EoMPLS) and Virtual Private LAN Service (VPLS) have been used for this purpose, DCI presents new requirements and challenges not fully addressed today.  To keep the data center always on, and to utilize all the resources and links as efficiently as possible, data centers need all-active redundancy and load balancing. The technology should be as simple as possible to provision and manage Read More »

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Evolving Provider L2VPN Services with E-VPN

A team of us at Cisco has been working, together with industry colleagues, on defining and standardizing a new Layer 2 VPN solution known as Ethernet Virtual Private Network or E-VPN. In this post, I will discuss the key requirements that helped shape this solution, and attempt to shed some light on the drivers for the technology and how it enables the evolution of Service Provider L2VPN offerings. Read More »

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Overlays, Underlays and the New World Order

The networking industry has recently developed a renewed interest in virtual overlays, often wrapped in an “SDN as the controller” context. Amidst the promise, the hope and the hype, the following questions present themselves:

  • What exactly is an overlay?
  • What distinguishes an overlay from a VPN?
  • How decoupled can an overlay be from the underlay network and what are the tradeoffs?
  • What are the advantages of overlays and will they emerge as the new networking world order? Read More »

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