Alibaba Cloud Express Connect offers point-to-point connectivity between networks. To ensure communication, a peering connection (VRouter interface) must be established between two network instances, and a static route must then be configured. These features impact the ease of use of the product, so for in-cloud communication using the full mesh connectivity of the Cloud Enterprise Network (CEN) with automatic dynamic routing learning is a better choice.
Concepts and Differences
Express Connect (EC) is a service that helps you build private network communication channels between VPCs or between a VPC and your local IDC. These channels feature increased network topology flexibility and enhanced cross-network communication quality and security. Express Connect also helps you avoid unstable network quality, and prevents data theft during transmission.
Cloud Enterprise Network (CEN) is a service that allows you to create a global network for rapidly building a distributed business system with a hybrid cloud computing solution. CEN enables you to build a secure, private, and enterprise-class interconnected network between VPCs in different regions and your local data centers. CEN provides enterprise-class scalability that automatically responds to your dynamic computing requirements.
Alibaba Cloud Express Connect and CEN differ in these aspects:
- Networking: Express Connect is a point-to-point solution. CEN supports a network of connections.
- Route Management: Express Connect is set up manually. CEN supports dynamic configurations.
- Bandwidth: Express Connect traffic usage is based on individual connections. CEN traffic usage is based on overall usage.
If a physical connection is established for access, no change is needed for the physical connection between your IDC and Alibaba Cloud Virtual Border Router (VBR). You simply need to change the connection mode from the VBR to the VPC instance.
Offline migration is the simplest method, as only the network between the VBR and VPC instance is disconnected.
- Create a CEN
- Perform step 1 in the tutorial. https://www.alibabacloud.com/help/doc-detail/65885.htm
- Delete the EC
- Click Console > Express Connect > VPC Peering Connections > VBR-to-VPC. Click “…” on the side of the page. Click Delete on the menu that expands.
- Note: Submit a ticket to release a subscription-type peering connection at the backend. If cross-region charges are incurred, you may submit a ticket to refund the balance.
- Load VBR and VPC instances on CEN
- Perform step 2 in the tutorial https://www.alibabacloud.com/help/doc-detail/65885.htm
- Note: If the VBR and VPC instances are located in the same region, you do not need to purchase a bandwidth package. If VBR and VPC instances are located in different regions, you need to purchase a bandwidth package and configure the bandwidth. Perform step 3 in the preceding tutorial.
- Other Configurations
- The migration duration refers to the period required for loading the VBR and VPC instances on CEN, and configuration of the bandwidth after deletion of the EC. For networks with a simple topology this is estimated to take 30 minutes.
Express Connect Application Limitations
Express Connect primarily provides the following two functions:
- Establishes a hybrid cloud to ensure communication over the ISP’s physical connection between your IDC and Alibaba Cloud.
Off-cloud IDC - ISP's physical connection - Alibaba Cloud VBR - Alibaba Cloud VPC
- Ensures communication between Alibaba Cloud VPCs in the same region or across regions.
Limitations on Hybrid Cloud
Traffic is forwarded through VBRs.
Limitations on Communication between in-cloud VPCs
The intermediate VPC does not support traffic forwarding.
Why Migrate to CEN?
Cloud Enterprise Network (CEN) will become the main in-cloud peering product of Alibaba Cloud. Compared with Express Connect, CEN offers the following advantages:
- Creation of VRouter interfaces is unnecessary.
- Route configuration is unnecessary.
- FullMesh connectivity is established.
These advantages will eliminate the limitations on application scenarios of Express Connect.
Learn more about Alibaba Cloud’s Cloud Enterprise Network (CEN) at https://www.alibabacloud.com/help/doc-detail/59870.htm