Considerations in Designing DCI (Data Centre Interconnect) in Full Mesh VPLS/ Multicast Enable WAN over OTV Tunne

VPLS/ MPLS is one of the most popular Wide Area Network (WAN) technologies used today by service providers. VPLS depends on pseudowires (PW) within Multiprotocol Label Switching (MPLS) network to emulate Ethernet connectivity in a full mesh topology, to multiple remote sites, sharing an Ethernet broadcast domain. As IP multicast services continue to be offered, many customers find it desirable to extend their multicast applications to remote sites, where traditional technologies fail to support such connectivity. A layer-2 VPN service using VPLS supports the extension of multicast services to remote sites. In this paper, the impact of a full mesh VPLS with the interoperability of Cisco Overlay Transport Virtualization (OTV) and multicast traffic has been analyzed. The paper concludes that an inadequately designed full mesh VPLS based WAN can have a significant negative impact on overall WAN performance in terms of reachability and packet loss for data, voice, and multicast traffic on the same customer edge (CE) device. The paper further proposes a design solution to avoid drastic impacts on the overall WAN performance when a large amount of multicast traffic is to be transported.