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Cloud Enterprise Network:Release notes

Last Updated:Mar 25, 2026

This topic highlights new CEN features and provides links to related documentation.

February 2026

Feature name

Change type

Description

Release date

Related documentation

Seamless payer change for cross-account network instances

New

For cross-account network instances, you can change the payer for TR connection and traffic fees without disrupting traffic.

2026-02-03

Authorize cross-account network instances

November 2025

Feature

Change type

Description

Release date

Related documentation

TR flow log delivery to the NIS traffic analyzer

New

You can now send flow logs from a transit router (TR) to the NIS traffic analyzer.

2025-11-25

Flow logs

Resource reservation for transit routers

New

In latency-sensitive scenarios, resource reservation for transit routers (TRs) reduces communication latency between TRs and ECS instances and minimizes network jitter.

2025-11-11

Resource reservation for transit routers

To enable this feature, contact your account manager.

October 2025

Feature

Type

Description

Release date

Related documents

TR route table limit increased to 50

Enhancement

Each Transit Router now supports up to 50 route tables.

2025-10-14

limits

August 2025

Feature name

Change type

Description

Release date

References

MED

New

ECR route entries now support the MED attribute. When TRs from multiple regions are connected to an ECR, you can set a default MED value on the ECR for a specific TR. This setting lets you designate a preferred path to prevent suboptimal traffic detours between the TRs.

Important

To enable this feature for pre-existing network environments where TRs from multiple regions connect to an ECR, contact Alibaba Cloud.

2025-08-19

TR+ECR multi-path routing

November 2024

Feature

Change type

Description

Release date

Related documents

Flow logs

Improvement

Flow logs now capture traffic for Enterprise Edition Transit Router instances, VPC connections, VPN connections, and VBR connections.

2024-11-14

Flow logs

Dual-tunnel mode for VPN connections

Improvement

VPN connections now use dual-tunnel mode. Each IPsec-VPN connection consists of two tunnels that automatically form an Equal-Cost Multipath Routing (ECMP) link. If one tunnel fails, traffic is automatically routed through the other, ensuring high availability for the IPsec-VPN connection. In regions with multiple availability zones, the two tunnels are distributed across different availability zones, providing zone-level disaster recovery.

2024-11-26

Create a VPN connection

October 2024

Feature

Change type

Description

Release date

Related documentation

IGMP

New

Transit Router now supports Internet Group Management Protocol (IGMP). When you establish a multicast network using a Transit Router, you no longer need to manually specify multicast sources and members. The Transit Router dynamically adds and removes them based on IGMP. This lets you quickly add resources in multiple VPCs to the multicast network or remove them, improving management and deployment efficiency.

2024-10-11

September 2024

Feature name

Change type

Description

Release date

Related documentation

IPv6

New

Enterprise Edition Transit Router instances now forward IPv6 traffic and can learn and propagate IPv6 routes by default. To enable IPv6 communication between Virtual Private Cloud (VPC) instances or between cloud and on-premises environments, connect your VPC, Express Connect Router (ECR), and Virtual Border Router (VBR) instances to an Enterprise Edition Transit Router. This connection enables intra-region and cross-region IPv6 communication among the connected VPCs and the local networks of the ECR and VBR instances.

2024-09-10

Transit Router IPv6 overview

July 2024

Feature name

Change type

Description

Release date

Related documentation

Monitor CEN resources

Enhancement

  • CEN now supports availability zone-level monitoring for enterprise edition transit router instances and network instance connections (VPC, ECR, VPN, and VBR connections).

  • You can now monitor traffic on network instance connections that either matches a blackhole route or does not match any route.

2024-07-02

Monitor CEN resources

June 2024

Feature name

Change type

Description

Release date

Related documentation

Route quota for Enterprise Edition Transit Router

Optimization

An Enterprise Edition Transit Router now supports up to 10,000 routes per route table.

An Enterprise Edition Transit Router instance supports a maximum of 40,000 routes across all its route tables.

2024-06-25

Limits

February 2024

Feature name

Change type

Description

Release date

Related documentation

ECR connection

New

You can now connect an Express Connect Router (ECR) instance to an Enterprise Edition Transit Router. This connection enables the associated data center to communicate with other networks through the Enterprise Edition Transit Router.

2024-02-21

Create an ECR connection

December 2023

Feature

Change type

Description

Date

Documentation

Line types

New

Inter-region connections now support Platinum and Gold line types. The Gold line type is ideal for less network-sensitive workloads, such as data synchronization and data migration. The Platinum line type is better suited for workloads that are highly sensitive to network jitter and latency, such as securities trading, online voice, and video conferencing.

2023-12-06

September 2023

Feature

Type

Description

Release date

References

Transit Router Savings Plan

New

A Transit Router Savings Plan is a discount plan that offers lower data transfer fees in exchange for a spending commitment over a fixed term. Once active, the plan automatically offsets the data transfer fees for Enterprise Edition Transit Routers.

2023-09-04

What Is a Transit Router Savings Plan?

May 2023

Feature

Type

Description

Release date

References

Quick configuration of traffic marking policies

Enhancement

You can now quickly add traffic classification rules when configuring a traffic marking policy.

2023-05-17

Create a traffic marking policy

March 2023

Feature

Type

Description

Release date

References

route synchronization

New

Route synchronization lets you control how an Enterprise Edition transit router propagates routes from its route tables to attached network instances.

2023-03-30

Route synchronization

aggregate route

New

Enterprise Edition transit routers now support aggregate routes. You can combine multiple routes with similar destination CIDR blocks and the same next hop into a single aggregate route. When route synchronization is enabled for a VPC, the transit router propagates only the aggregate route, not the more specific routes. This reduces route entries in the VPC's route table and improves routing efficiency.

2023-03-30

Aggregate routes

transit router diagnostics

New

CEN integrates with Network Intelligence Service (NIS) to provide transit router diagnostics. This feature lets you diagnose transit router instances, identify issues, and receive resolution recommendations to independently troubleshoot related network problems.

2023-03-22

Diagnose a transit router

reachability analyzer

New

CEN now integrates with Network Intelligence Service (NIS) to support the reachability analyzer. The reachability analyzer lets you diagnose network connectivity between your resources.

2023-03-22

Use the reachability analyzer

Monitor transit router instances

New

The integration with CloudMonitor lets you view monitoring data for your transit router instances and create threshold-based alerts for traffic anomalies.

2023-03-17

Monitor CEN resources

multi-region ECMP routing for VBRs

New

By default, when an Enterprise Edition transit router learns routes to the same destination CIDR block from multiple VBRs, it prioritizes the route from the region whose ID comes first alphabetically, assuming all other route attributes are identical. You can now enable multi-region ECMP routing for VBRs. When enabled, these routes form an ECMP group that load-balances traffic across them.

2023-03-15

Multi-region ECMP routing for VBRs

November 2022

Feature

Type

Description

Release date

References

Transit router CIDR block

New

A transit router CIDR block is a custom CIDR block that you can assign to a transit router. It functions similarly to the CIDR block assigned to a router's loopback interface. The transit router uses this CIDR block to allocate IP addresses for IPsec connections and Connect Peers.

2022-11-22

Transit router CIDR blocks

August 2022

Feature

Type

Description

Release date

References

IPsec-VPN connections

New

Enterprise Edition transit routers now support IPsec-VPN connections, which allow on-premises data centers to connect directly to a transit router to communicate with other networks.

2022-08-05

Create a VPN connection

Prefix lists

New

When you associate a prefix list from a VPC with the route table of an Enterprise Edition transit router, the system automatically adds routes for all CIDR blocks in the prefix list to the transit router's route table.

2022-08-04

Prefix lists

June 2022

Feature

Type

Description

Release date

References

Flow logs

New

Flow logs can now capture traffic from VBR connections.

2022-06-17

Flow logs

Multicast

New

Transit Router (Enterprise Edition) now supports multicast. After you attach network instances to a Transit Router (Enterprise Edition), you can create and manage multicast networks. The Transit Router forwards multicast traffic between the network instances.

2022-06-07

Manage multicast

May 2022

Feature

Type

Description

Release date

References

VPC connections

Optimization

CEN has optimized VPC connections for Enterprise Edition transit routers. This update enables shortest path forwarding for traffic between the routers and connected VPC instances.

2022-05-31

Announcement: Optimization of VPC Connections for Enterprise Edition Transit Routers

December 2021

Feature

Type

Description

Release date

References

billing by payer account

New

When an Enterprise Edition transit router connects to a cross-account VPC or VBR, the connection fee and data transfer fee can be charged to either the Alibaba Cloud account that owns the Enterprise Edition transit router or the one that owns the network instance.

2021-12-24

Granting permissions on a cross-account network instance

November 2021

Feature

Type

Description

Release date

References

Flow logs

New

Flow logs now capture information about inter-region traffic between Transit Routers. Use this data to analyze inter-region traffic patterns, troubleshoot network issues, and optimize data transfer costs.

2021-11-08

Configure a flow log

April 2021

Feature

Type

Description

Release date

References

quality of service (QoS) policy

New

A quality of service (QoS) policy lets you mark traffic from different services and apply bandwidth throttling. This prevents non-core services from consuming the bandwidth of core services, which ensures sufficient bandwidth for your key operations and improves overall network efficiency.

2021-04-30

Use traffic scheduling to control inter-region bandwidth

CCN bandwidth multiplexing

New

With CCN bandwidth multiplexing, a CCN transit router and a regional transit router in the same region can share inter-region bandwidth in real time. This eliminates the need for manual configuration adjustments and increases bandwidth flexibility.

2021-04-30

CCN bandwidth multiplexing

February 2021

Feature

Type

Description

Release date

References

Enterprise Edition transit router

New

The Enterprise Edition transit router provides extensive network interconnection and route management capabilities, such as custom route tables, route entries, and routing policies to help you build flexible and interconnected cloud networks.

2021-02-20

How transit routers work

Transit router

New

A transit router is a regional network hub that connects network instances within and across regions, enabling communication throughout your entire network.

2021-02-20

How transit routers work

CEN console

New

The CEN console includes all features from the previous version and uses transit routers to connect network instances within and across regions. It also provides enhanced routing features to help you build a flexible, reliable, and scalable enterprise-grade global network.

2021-02-20

What is CEN?

May 2019

Feature

Type

Description

Release date

References

PrivateZone

New

PrivateZone provides private domain name resolution and management within a VPC. CCN and VBR instances attached to a CEN can access PrivateZone over CEN.

2019-05-16

Configure access to PrivateZone

October 2018

Feature

Type

Description

Release date

References

Overlapping routing

New

CEN can now learn routes with the same prefix but different mask lengths, improving network flexibility.

2018-10-12

This feature is enabled by default in the console and cannot be disabled.

Delete health check configurations

New

CEN now supports deleting health check configurations.

2018-10-12

Configure VBR health checks

Alert rules

New

The CEN console now provides a shortcut to CloudMonitor, allowing you to quickly set alert rules for your network resources and improve operational efficiency.

2018-10-12

Create a threshold-based alert rule for a bandwidth plan

Detach network instances

New

CEN now supports detaching network instances, including VPC, VBR, and CCN instances.

2018-10-12

Delete a network instance connection

Attach cross-account CCN instances

New

CEN now supports attaching cross-account CCN instances to connect your on-premises networks.

2018-10-12

Grant permissions on a network instance that belongs to another account and Associate a CCN instance with a transit router

July 2018

Feature

Type

Description

Release date

References

Route advertising

New

You can now advertise VPC routes to CEN via the CEN console.

2018-07-30

Propagate routes to a transit router