You can use Cloud Enterprise Network (CEN) to establish private network connections between virtual private clouds (VPCs), and between VPCs and data centers. CEN enables intra-region and inter-region network communication. This topic describes how to use the previous version of the CEN console, the billing rules, and the limits.

Switch to the previous version

Log on to the CEN console. If you are logged on to the latest version, you can click Previous Version on the Instances page.

Important The previous version of the CEN console was discontinued on March 31, 2022. We recommend that you use the latest version. For more information, see Upgrade to the latest CEN console version.
Instances - previous version

Billing

Intra-region network communication does not require bandwidth plans. However, inter-region network communication requires bandwidth plans. For more information about the billing of bandwidth plans, see Billing rules.

Limits

Before you use CEN, read and understand the following limits.

Item Default quota Adjustable
The maximum number of CEN instances that can be created by each Alibaba Cloud account 5
You can use one of the following methods to increase quotas:
The maximum number of network instances that can be attached to a CEN instance in each region 10 N/A
The maximum number of bandwidth plans that you can purchase for each CEN instance that connects the same pair of areas. 1 N/A
The maximum number of route entries that can be created for each CEN instance 100 N/A
Limits on virtual private clouds (VPCs) that have ClassicLink enabled The VPCs cannot use the CIDR block 10.0.0.0/8. N/A
Network instances The network instances attached to a CEN instance do not support Express Connect. N/A
Allow network instances to share NAT gateways through CEN Not supported N/A
Access cloud services across regions

Cloud services refer to services that are deployed in VPCs and use the CIDR block 100.64.0.0/10. Cloud services provided by Alibaba Cloud include Log Service, Object Storage Service (OSS), and Data Transmission Service (DTS). For more information, see Access cloud services.

Not supported N/A
Allow cloud services to access network instances attached to CEN Not supported N/A
Attach only one cloud connect network (CCN) instance in each region

For more information, see Introduction to CCN.

Not supported N/A
Subnet routing
  • For a VPC that learns routes from a CEN instance:

    If the VPC is attached to a CEN instance, all route tables of the VPC, including the system route table and custom route tables, learn routes from the CEN instance.

    Note If the VPC was attached to the CEN instance before October 22, 2019, you must re-attach the VPC to the CEN instance. Otherwise, the custom route tables of the VPC cannot learn routes from the CEN instance.
  • For a CEN instance that learns routes from a VPC:

    If the VPC has multiple route tables, the CEN instance learns routes only from the system route table of the VPC.

N/A

Use cases

You can use CEN to enable intra-region and inter-region network communication. For more information, see the following topics: