Cloud Enterprise Network：Use traffic scheduling to limit bandwidth for inter-region connections

Introduction to traffic scheduling

Overview

After you use Cloud Enterprise Network (CEN) to establish inter-region communication, traffic from different services, including video conferencing, voice communication, software as a service (SaaS), and file transmission, is transmitted over the inter-region connections. Different service traffic has different requirements for networks, as described in the following examples:

• Video conferencing and voice communication require stable networks with low latency. Packet loss and network jitter lower the communication quality.

• SaaS requires immediate response. Network congestion decreases user experience.

• File transmission requires high network throughput but is insensitive to network performance issues, such as network latency and network jitter. Sufficient bandwidth resources are required if you want to maintain high network throughput.

The maximum bandwidth of a bandwidth plan that is shared by inter-region connections is a fixed value. As a result, different services may compete for bandwidth resources and some services may waste bandwidth resources. This decreases network performance. If file transmission consumes a large percentage of bandwidth resources, network latency during video conferences or voice communication increases. In some cases, network disconnections may occur. To prevent such issues, you can use the traffic scheduling feature to classify network traffic and allocate bandwidth resources to different services. This improves network quality and minimizes network resource waste.

How it works

Prerequisites

• Only inter-region connections created on Enterprise Edition transit routers support the traffic scheduling feature.

• Traffic scheduling applies only to outbound traffic on Enterprise Edition transit routers.

  If you create an inter-region connection between the China (Hangzhou) region and the China (Qingdao) region, and enable traffic scheduling for the transit router in the China (Hangzhou) region, traffic scheduling applies to the network traffic that flows from China (Hangzhou) to China (Qingdao). Traffic scheduling allocates bandwidth resources to different services. Traffic scheduling does not apply to the network traffic that flows from China (Qingdao) to China (Hangzhou).

  Important

  To ensure that services in both regions have sufficient bandwidth resources, we recommend that you create traffic marking policies and QoS policies for both inbound and outbound traffic.

• The following table describes the resource quotas on the traffic scheduling feature.

  Item	Default value	Adjustable
  The maximum number of traffic classification rules supported by a transit router	500	No
  The maximum number of QoS queues supported by a QoS policy	64	No

Configuration examples

The preceding scenario is used as an example to describe how to configure traffic scheduling. An enterprise created a virtual private cloud (VPC) named VPC1 in the China (Hangzhou) region and another VPC named VPC2 in the China (Qingdao) region. The enterprise used Elastic Compute Service (ECS) to deploy an application named ECS01 in VPC1, and deployed services including file transmission and software as a service (SaaS) services in VPC2. VPC1 is connected to VPC2 through CEN and Enterprise Edition transit routers. However, users may experience high latency and transmission interruptions when they use the file transmission service and SaaS services that are deployed on ECS01 in VPC1. The enterprise found out that other services consumed a large percentage of bandwidth during file transmission over the inter-region connection. As a result, the file transmission and SaaS services do not have sufficient bandwidth resources.

Prerequisites

An inter-region connection is created by using CEN and Enterprise Edition transit routers. For more information, see Use CEN and Enterprise Edition transit routers to connect VPCs in different regions and Alibaba Cloud accounts.

Step 1: Create a traffic marking policy

A traffic marking policy captures network traffic based on traffic classification rules and marks the traffic with DSCP values.

1. Log on to the CEN console.

2. On the Instances page, click the ID of the CEN instance that you want to manage.

3. On the Basic Information > Transit Router tab, click the ID of the transit router on which the inter-region connection is created.

4. On the details page of the transit router, click the Traffic Marking tab.

5. On the Traffic Marking tab, click Create Traffic Marking Policy.

6. On the Create Traffic Marking Policy page, set the following parameters and click OK.

   Basic Information

   Parameter	Description
   Policy Name	Enter a name for the traffic marking policy.
   Policy Description	Enter a description for the traffic marking policy.
   Priority	Enter a priority for the traffic marking policy. Valid values: 1 to 100. A smaller value indicates a higher priority. When a packet enters an inter-region connection, the packet is matched against the traffic marking policies in descending order of priority. If the packet matches a traffic classification rule in a traffic marking policy, the packet is a match and the DSCP value of the traffic marking policy is added to the packet. If the packet does not match a traffic marking policy, no DSCP value is added to the packet.
   Specified DSCP	Enter a DSCP value that you want to add to the network traffic that matches the traffic classification rules. When you create a QoS policy, you can use the DSCP value to schedule network traffic to different queues. Valid values: 0 to 63. The DSCP value of each traffic marking policy set for a transit router must be unique.

   Traffic Classification Rules

   You can select Manual or Automatic to create a traffic classification rule.

   Manual generation

   Parameter	Description
   Address Type	Address type of traffic packet. Valid values: IPv4: Only matches IPv4 traffic. IPv6: Only matches IPv6 traffic. If this parameter is left empty, it matches both IPv4 traffic and IPv6 traffic.
   6-tuple Name	Enter a name for the traffic classification rule.
   Protocol	Select a protocol to match data packets. Multiple protocols, such as HTTP, HTTPS, UDP, TCP, and SSH, are supported. The protocols in the console shall prevail.
   Source CIDR Block	Enter a source CIDR block to match data packets. The system matches the source IP addresses of packets against the specified source CIDR block. If you do not set this parameter, it indicates that all source IP addresses are considered a match.
   Source Port	Enter a source port range to match data packets. The system matches the source ports of packets against the specified source port range. If you do not set this parameter, it indicates that all source ports are considered a match. Valid values: -1 and 1 to 65535. Formats: 1/200: specifies ports that range from 1 to 200. 80/80: specifies port 80. -1/-1: specifies all ports. -1: an invalid value. Only -1/-1 is valid.
   Destination CIDR Block	Enter a destination CIDR block to match data packets. The system matches the destination IP addresses of packets against the specified destination CIDR block. If you do not set this parameter, it indicates that all destination IP addresses are considered a match.
   Destination Port	Enter a destination port range to match data packets. The system matches the destination ports of packets against the specified destination port range. If you do not set this parameter, it indicates that all destination ports are considered a match. Valid values: -1 and 1 to 65535. Formats: 1/200: specifies ports that range from 1 to 200. 80/80: specifies port 80. -1/-1: specifies all ports. -1: an invalid value. Only -1/-1 is valid.
   DSCP	The DSCP value used to match data packets. The system matches the DSCP value of each data packet against the specified DSCP value. If you do not set this parameter, it indicates that all DSCP values are considered a match. Important The DSCP value that you specify for this parameter indicates the DSCP value that packets carry before they are transmitted over the inter-region connection. For example, a data center uses CEN to access a VPC that is deployed in another region. If a DSCP value is specified for data packets from the data center, you can specify a DSCP value in the traffic marking policy to match data packets from the data center against the specified DSCP value. If no DSCP value is specified for data packets from the data center, you do not need to specify one in the traffic marking policy. In this case, all DSCP values are considered a match.
   6-tuple Description	Enter a description for the traffic classification rule.

   Automatic generation

   This method allows you to specify the CIDR block of a VPC as the source CIDR block or destination CIDR block. You only need to set the Source CIDR Block and Destination CIDR Block parameters and click Automatically Generate Rules. Then, the system automatically sets the Protocol, Source Port, Destination Port, and DSCP parameters.

   Set Method to Automatic, set the Rule Name, Source CIDR Block, and Destination CIDR Block parameters, and then click Automatically Generate Rules.

   Important

   • After you click Auto Generate, you must select the generated rule and click OK at the bottom of the page before the system can apply the generated rule. After you click Auto Generate, if you click OK without selecting the generated rule, the rule is not applied.

   • If you want to create more traffic classification rules, add the source and destination CIDR blocks to the Source CIDR Block and Destination CIDR Block parameters and click Auto Generate. Then, the system generates and lists all traffic classification rules based on the specified source CIDR blocks and destination CIDR blocks. You can select the traffic classification rules that you want.

   • After you click Auto Generate, if you want to modify a traffic classification rule, modify the Rule Name, Source CIDR Block, and Destination CIDR Block parameters. Then, click Auto Generate, and select the rules that you want to apply.

   Parameter	Description
   Rule Name	Enter a name for the traffic classification rule.
   Source CIDR Block	Enter source CIDR blocks for the traffic classification rule. Click Quick Add on the right side. In the Source CIDR Block dialog box, select the CIDR block of VPC from the left-side drop-down list, click the icon to add the CIDR block, and then click OK. If you want to remove it, select the CIDR block from the right-side drop-down list and click the icon in dialog box.
   Destination CIDR Block	Enter destination CIDR blocks for the traffic classification rule. Click Quick Add on the right side. In the Destination CIDR Block dialog box, select the CIDR block of VPC from the left-side drop-down list, click the icon to add the VPCs, and then click OK. If you want to remove it, select the CIDR block from the right-side drop-down list and click the icon in dialog box.
   Protocol	The Protocol, Source Port, Destination Port, and DSCP parameters are automatically configured and cannot be modified. The following parameters are automatically configured: Protocol: matches all protocols by default. Source Port: matches all ports by default. Destination Port: matches all destination ports by default. DSCP: matches all DSCP values by default.
   Source Port
   Destination Port
   DSCP

7. Repeat Step 3 to Step 6 to create a traffic marking policy for the transit router in the peer region.

   In this example, a traffic marking policy is manually created for each of the China (Hangzhou) and China (Qingdao) regions. The following table describes the parameters.

   Note

   In the following table, N/A indicates that the parameter is ignored and the default match rule is applied.

   Region	China (Hangzhou)			China (Qingdao)
   Parameter	Traffic Marking Policy 1	Traffic Marking Policy 2	Traffic Marking Policy 3	Traffic Marking Policy 1	Traffic Marking Policy 2	Traffic Marking Policy 3
   Policy Name	File	SaaS	Other	File	SaaS	Other
   Priority	5	10	15	5	10	15
   Specified DSCP	5	10	15	5	10	15
   Traffic classification rule
   Address Type	N/A	IPv6	N/A	N/A	IPv6	N/A
   Protocol	N/A	HTTP	HTTPS	N/A	HTTP	HTTPS
   Source CIDR Block	192.168.0.0/16	2408:****:a800::/56	192.168.0.0/16	172.16.10.0/24	2408:****:b440::/64	172.16.30.0/24
   Source Port	1/200	N/A	1/200	25/25	80/80	443/443
   Destination CIDR Block	172.16.10.0/24	2408:****:b440::/64	172.16.30.0/24	192.168.0.0/16	2408:****:a800::/56	192.168.0.0/16
   Destination Port	25/25	80/80	443/443	1/200	N/A	1/200
   DSCP	25	30	N/A	25	30	N/A
   Traffic marking policy	Matches packets that are from 192.168.0.0/16 and port 1 to port 200, are destined for 172.16.10.0/24 and port 25, and carry a DSCP value of 25. A DSCP value of 5 is added to such packets.	Matches packets that use HTTP, are from 2408:****:a800::/56, are destined for 2408:****:b440::/64 and port 80, and carry a DSCP value of 30. A DSCP value of 10 is added to such packets.	Matches packets that use HTTPS, are from 192.168.0.0/16 and port 1 to port 200, and are destined for 172.16.30.0/24 and port 443. A DSCP value of 15 is added to such packets.	Matches packets that are from 172.16.10.0/24 and port 25, are destined for 192.168.0.0/16 and port 1 to port 200, and carry a DSCP value of 25. A DSCP value of 5 is added to such packets.	Matches packets that use HTTP, are from 2408:****:b440::/64 and port 80, are destined for 2408:****:a800::/56, and carry a DSCP value of 30. A DSCP value of 10 is added to such packets.	Matches packets that use HTTPS, are from 172.16.30.0/24 and port 443, and are destined for 192.168.0.0/16 and port 1 to port 200. A DSCP value of 15 is added to such packets.

Step 2: Create a QoS policy

Create queues based on the DSCP values, and specify a maximum bandwidth value for each queue.

1. Log on to the CEN console.

2. On the Instances page, click the ID of the CEN instance that you want to manage.

3. On the Basic Information > Transit Router tab, click the ID of the transit router on which the inter-region connection is created.

4. On the details page of the transit router, click the Cross-region Connections tab.

5. On the Cross-region Connections tab, find the inter-region connection that you want to manage and click Set in the QoS Policy column.

6. On the Configure Cross-region QoS Policy page, configure the parameters and click OK. The following table describes the parameters.

   Parameter	Description
   Basic Information
   Policy Name	Enter a name for the QoS policy.
   Policy Description	Enter a description for the QoS policy.
   Inter-region Connection	Select the inter-region connection for which you want to apply the QoS policy.
   Guaranteed Bandwidth Allocation Mode	Set the guaranteed bandwidth allocation mode to by percentage or by absolute value. Note You can select the guaranteed bandwidth allocation mode when creating a QoS policy. To modify the mode, you must delete the existing QoS policy and create a new one.
   Queues
   Queue Name	Enter a name for the queue.
   Queue Description	Enter a description for the queue.
   Matching DSCP	Enter a DSCP value to match data packets. The DSCP value refers to the one that you want to add to data packets which match the traffic marking policy. The DSCP value is the same as the one specified for the DSCP parameter when you create the traffic marking policy. Data packets that match the specified DSCP value are scheduled to the current queue. You can specify multiple DSCP values for a queue. Separate DSCP values with commas (,).
   Throttling Bandwidth	Enter the maximum bandwidth of the queue. Measured in % when Guaranteed Bandwidth Allocation Mode is set to by percentage. A value of 30 specifies that the current queue can consume at most 30% of the total bandwidth of the inter-region connection. Measured in Mbps when Guaranteed Bandwidth Allocation Mode is set to by absolute value. A value of 30 specifies the maximum bandwidth of the inter-region connection for the queue is 30Mbps.

7. Repeat Step 3 to Step 6 to create a QoS policy for the transit router in the peer region.

   The following table describes the QoS policies created for the transit routers in the China (Hangzhou) and China (Qingdao) regions.

   Region	Policy Name	Cross-region Connection	Guaranteed Bandwidth Allocation Mode	Queue
   				Queue Name	Matching DSCP	Throttling Bandwidth (in percentage: 30 specifies 30% of the total bandwidth of the inter-region connection)
   China (Hangzhou)	QoS-Policy-HZ	Select the inter-region connection that connects the China (Hangzhou) region to the China (Qingdao) region.	Select by percentage	Queue-File	5	30
   				Queue-SaaS	10	20
   				Queue-Other	15	50
   China (Qingdao)	QoS-Policy-QD			Queue-File	5	30
   				Queue-SaaS	10	20
   				Queue-Other	15	50

   After you complete the preceding steps, the QoS policies allocate bandwidth resources based on the maximum bandwidth value specified for each queue.

What to do next

Modify a traffic marking policy

After you create a traffic marking policy, you can modify the name and description of the policy, and add or delete traffic classification rules for the policy. You cannot modify the priority or DSCP values of the policy.

1. Log on to the CEN console.

2. On the Instances page, click the ID of the CEN instance that you want to manage.

3. On the Basic Information > Transit Router tab, click the ID of the transit router on which the inter-region connection is created.

4. On the details page of the transit router, click the Traffic Marking tab, find the traffic marking policy that you want to manage, and then click Edit in the Actions column.

5. In the Traffic Marking Policy Details panel, enter a name and description for the traffic marking policy and specify a traffic classification rule for the traffic marking policy.

   You can only add or delete a traffic classification rule, but cannot modify a traffic classification rule. If the settings of a traffic classification rule cannot meet your requirements, you can delete the rule and add a new one.

Delete a traffic marking policy

You must delete all the traffic classification rules before you can delete a traffic marking policy. The following steps show how to delete a traffic classification rule and a traffic marking policy.

1. Log on to the CEN console.

2. On the Instances page, click the ID of the CEN instance that you want to manage.

3. On the Basic Information > Transit Router tab, click the ID of the transit router on which the inter-region connection is created.

4. On the details page of the transit router, click the Traffic Marking tab, find the traffic marking policy that you want to manage, and then click Edit in the Actions column.

5. In the Traffic Marking Policy Details panel, find the traffic classification rule that you want to manage in the Traffic Classification Rules section, and click Delete in the Actions column. In the Delete Traffic Classification Rule message, click OK.

   Repeat the preceding steps to delete all traffic classification rules that you want to delete from the traffic marking policy.

6. In the upper-right corner of the Traffic Marking Policy Details panel, click Delete. In the Delete Traffic Marking Policy message, click OK.

Modify a QoS policy

After you create a QoS policy, you can modify the name, description, and queue settings of the policy.

1. Log on to the CEN console.

2. On the Instances page, click the ID of the CEN instance that you want to manage.

3. On the Basic Information > Transit Router tab, click the ID of the transit router on which the inter-region connection is created.

4. On the details page of the transit router, click the Cross-region Connections tab, find the inter-region connection that you want to manage, and then click details in the QoS Policy column.

5. In the Cross-region QoS Policy Details panel, modify the name, description, and queues of the QoS policy.

Delete a QoS policy

You must delete all the queues before you can delete a QoS policy. The following steps show how to delete a queue and a QoS policy.

1. Log on to the CEN console.

2. On the Instances page, click the ID of the CEN instance that you want to manage.

3. On the Basic Information > Transit Router tab, click the ID of the transit router on which the inter-region connection is created.

4. On the details page of the transit router, click the Cross-region Connections tab, find the inter-region connection that you want to manage, and click details in the QoS Policy column.

5. In the Cross-region QoS Policy Details panel, find the queue that you want to manage in the Queues section, and click Delete in the Actions column. In the Delete Queue From QoS Policy message, click OK.

6. In the upper-right corner of the Cross-region QoS Policy Details panel, click Delete. In the Delete QoS Policy message, click OK.

References

Traffic marking policy

• CreateTrafficMarkingPolicy: Creates a traffic marking policy.

• AddTrafficMatchRuleToTrafficMarkingPolicy: Adds a traffic classification rule to a traffic marking policy.

• RemoveTrafficMatchRuleFromTrafficMarkingPolicy: Deletes a traffic classification rule from a traffic marking policy.

• DeleteTrafficMarkingPolicy: Deletes a traffic marking policy.

• ListTrafficMarkingPolicies: Queries the information about a traffic marking policy.

QoS policy

• CreateCenInterRegionTrafficQosPolicy: Creates a QoS policy for inter-region communication.

• CreateCenInterRegionTrafficQosQueue: Create a queue for a QoS policy.

• UpdateCenInterRegionTrafficQosPolicyAttribute: Modifies the name and description of a QoS policy.

• UpdateCenInterRegionTrafficQosQueueAttribute: Modifies a queue in a QoS policy.

• DeleteCenInterRegionTrafficQosQueue: Deletes a queue from a QoS policy.

• DeleteCenInterRegionTrafficQosPolicy: Deletes a QoS policy.

• ListCenInterRegionTrafficQosQueues: Queries QoS queues.

• ListCenInterRegionTrafficQosPolicies: Queries QoS policies.