We are stepping into the cloud era. More than 80% of network services will be deployed on the cloud, and cloud data centers (DCs) are becoming the new network traffic center. At Huawei Global Analyst Summit 2016, how to build a DC-centric cloud bearer backbone network is a hot topic.

Cloud DCs are deployed in different locations from legacy backbone networks' core nodes, making it a necessity to build a DCI network.
Cloud DCs need massive numbers of cloud computing and storage resources, featuring large coverage of equipment rooms and high energy demand. As such, cloud DCs are generally constructed in locations of low rent, abundant energy, and suitable climate so that they can be easily expanded. However, these locations are often far away from the population-dense cities where the core nodes of legacy IP backbone networks are usually deployed. For example, the super large DCs of China Telecom are deployed in Guizhou and Inner Mongolia, far away from Beijing, Shanghai, and Guangzhou, where their super core nodes used to be. Facebook also chose to place their DCs near the Arctic Circle in the city of Lulea of northern Sweden. Because the location for the network traffic center has changed, the existing backbone network can no longer be reused, which makes it a necessity to build a Data Center Interconnect (DCI) network.

Cloud services feature very low latency and traffic bursts, crying out for a full-mesh, flat network architecture based on intelligent traffic optimization.
Cloud services have strict latency requirements, and a full-mesh, flat network architecture is in need. For example, synchronous computing between DCs, VM live migration, disaster recovery and backup, and similar services all require a latency lower than 10 ms. A cloud-based DCI network must satisfy two requirements: First, a full-mesh, flat network where large DCs are just one hop away from each other must be constructed to meet low latency requirements. Second, rapid DC traffic growth introduces higher requirements for network devices — high-density 100GE ports and capabilities to smoothly evolve to 1T or 2T platforms. Currently, Huawei NE5000E provides the industry's highest 100GE port density, with a single NE5000E providing 256 x 100GE ports. It can be evolved from 400G to 1T or 2T, and allows in-service smooth expansion of multi-chassis clusters to meet the demands of network service development for the next five years or more.

Inter-DC traffic bursts and imbalance exist, requiring SDN-based traffic optimization.
Random inter-DC VM migrations cause traffic uncertainty. Additionally, popular Internet services, such as Alibaba's Double 11 online shopping event, bring about traffic bursts, causing traffic imbalance, partial link congestion, and low average link utilization across the network. Traditional traffic engineering methods based on network traffic prediction cannot handle congestion caused by traffic bursts. SDN traffic optimization technology monitors the network traffic of the entire network and makes adjustments in real time, achieving load balancing between links. Traffic can also be adjusted based on latency and other factors, ensuring user experience. In addition, SDN can implement IP+Optical synergy, including the centralized management of inter-layer resources and link planning and automatic service deployment, greatly reducing service provisioning time and increasing network-wide resource utilization. Huawei's SDN RR+/PCE+ traffic optimization technology and SDN IP+Optical technology are the first to achieve commercial use.

Huawei has taken the lead to carry out joint innovation with carriers in the DCI field to drive network transformation.
At CeBIT 2016, Huawei released the first SDN Bandwidth as a service (BaaS) solution, allowing users to customize bandwidth requirements through the web. SDN automatically converts the request into QoS guarantee policies and VPN policies at each layer from enterprise access to DCs, achieving end-to-end automatic leased line establishment and shortening the service provisioning time from weeks to within minutes. This provides carriers with new sources of revenue while improving user experience.

More importantly, as DCs now have a profound impact on the future development of the backbone network, Huawei has collaborated with China Telecom and other carriers to build the DCI dedicated network, achieving exploration and commercial deployment of DCI network reconstruction for the cloud era.

The construction of a smart DCI network, achieving cloud and network orchestration, will become an inevitable trend in the cloud era.