Ethernet’s success in local-area networks (LANs) is fueling the efforts to extend its reach to cover metro and long-haul networks. A key enabler for using Ethernet in the carrier’s network is its ability to efficiently support multipoint-to-multipoint (MP2MP) services. MP2MP service is the core underlying structure to enable standard Ethernet services such as Ethernet virtual private networks (E-VPNs). Since most of the research, standardization, and development have focused on designing protection architectures for point-to-point (P2P) Ethernet connections, protecting E-VPN services is an important research problem. Among the various transport methods for realizing carrier Ethernet, the wavelength-division multiplexing (WDM) optical network is a strong candidate. Wavelength channel rates are increasing from 10 to and even , and they can also coexist in the same fiber. We study the problem of cost-efficient provisioning of multi-bit-rate self-protected E-VPN demands over a carrier-grade Ethernet network employing WDM optical network (Ethernet over WDM) with mixed line rates (MLRs). We study two algorithms for self-protected E-VPN provisioning. The first algorithm reforms the original E-VPN topology and increases the provisioning rates of the E-VPN edge demands to create excess capacity that can be used for protection (E-VPN reformation). The second algorithm routes the E-VPN edge demands using the lowest available rate and establishes backup capacity for protecting the E-VPN (no E-VPN reformation). Our algorithms are tested on a 17-node German national network topology. The results show that using E-VPN reformation achieves significant cost reduction and significant improvement in the network’s performance by reducing the traffic-blocking ratio.
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