This topic describes how to use Global Accelerator (GA) to accelerate the delivery of IPv4 services for IPv6 clients. This improves user experience.

Prerequisites

IPv6 clients can connect to GA instances that are deployed in only the China (Beijing), China (Hangzhou), China (Shanghai), China (Shenzhen), and China (Hong Kong) regions. Make sure that your IPv6 clients belong to the preceding regions.

Background information

The following scenario is used as an example. The headquarters of a company is located in US (Silicon Valley). An on-premises server that provides IPv4 services is deployed in the headquarters. The employees of the company in China (Hong Kong) use only IPv6 clients. As the company develops, the employees in China (Hong Kong) need to use IPv6 clients to access the IPv4 services deployed in US (Silicon Valley). The employees also want to reduce issues such as network latency, network jitter, and packet loss caused by unstable cross-border Internet connections.

GA redirects requests from an IPv6 client in the China (Hong Kong) region to the nearest access point through an accelerated IP address. The access point receives the requests from the client, and forwards the requests to the Alibaba Cloud global network. GA then converts the IPv6 requests to IPv4 requests, automatically selects routes, and forwards the requests to the endpoint, which is the server in US (Silicon Valley). Scenarios

Procedure

Procedure

Step 1: Enter the required information about the web service that you want to accelerate

You can enter the required information about the accelerated web service in the GA console. The system recommends the GA instance and basic bandwidth plan based on your business requirements.

  1. Log on to the Global Accelerator console.
  2. In the upper-right corner of the Instances page, click Purchase Guide.
    Note Skip the step if it is your first time using GA.
    Purchase Guide
  3. In the Enter the required information to generate a list of recommended services section, enter the required information.
    • Acceleration Region: Select the region that requires acceleration. In this example, China (Hong Kong) is selected.
    • Service Region: Select the region where the origin servers are located. In this example, US (Silicon Valley) is selected.
    • ICP Filing: If you need to accelerate a web service, select Yes. If the service is not a web service, select No. In this example, No is selected.
      Note All websites must obtain an ICP number before they are permitted to provide services to users in mainland China. For more information, see What is an ICP filing?.
    • Server Area: Specify whether the backend servers are deployed on Alibaba Cloud. Off Alibaba Cloud is selected in this example.
    • Peak Bandwidth Range: Enter the bandwidth required during peak hours. Unit: Mbit/s. The value is set to 10 in this example.
    • Maximum Concurrent Connections: Specify the maximum number of concurrent connections that the GA instance supports. When the number of existing concurrent connections reaches the upper limit, new connection requests are dropped. The value is set to 5 thousand in this example.
  4. Click Generate Service List.
    After a service list is generated, you can view the list of recommended services. Recommended service list

Step 2: Purchase a GA service bundle

You can purchase a GA service bundle that includes the recommended GA instance and basic bandwidth plan.

  1. Click Generate Service List.
    Generate Service List
  2. On the buy page, set the following parameters:
    • Term: Select a subscription duration.
      Note The subscription duration applies to the services in the recommended service bundle. For example, if you set Term to 1 Year,the subscription duration of the specified GA instance, basic bandwidth plan, and cross-border bandwidth plan is set to one year.
    • Specification: Select a specification for the GA instance that you want to create. Small I (Specification Unit) is selected in this example.
    • Bandwidth Type: Select the type of the basic bandwidth plan. Premium is selected in this example.
  3. Click Buy Now to complete the payment.
  4. After you complete the payment, associate the basic bandwidth plan with the GA instance. For more information, see Bind a basic bandwidth plan.

Step 3: Add an acceleration area

After you purchase a GA instance, you can add an acceleration area, specify the region to which users belong, and then allocate bandwidth resources to the region.

  1. On the Instances page, find the GA instance that you created in Step 2 and click the instance ID.
  2. On the instance details page, click the Acceleration Areas tab, and click Add Region on the Asia Pacific tab.
  3. In the Add Acceleration Area dialog box, set the following parameters, and click OK.
    • Regions: Select the region where users are located. In this example, China (Hong Kong) is selected.
    • Bandwidth: Select a bandwidth value for the acceleration region. The value is set to 10 Mbit/s in this example.
    • Internet Protocol: Select the IP protocol of the clients that use GA. IPv6 is selected in this example.
      Note IPv6 is available to only users in the whitelist. If you want to use this feature but you are not included in the whitelist, submit a ticket.
After an acceleration area is added, GA assigns an IPv6 address to the acceleration region. The IPv6 address is used an accelerated IP address to accelerate connections. Accelerated IP addresses

Step 4: Add a listener

Listeners are used to monitor connection requests from clients. GA monitors connection requests received on the specified listener ports and forwards the requests to endpoints through the specified protocol.

  1. On the instance details page, click the Listeners tab and then click Add Listener.
  2. In the Configure Listener & Protocol wizard, set the following parameters for the listener:
    Listener
    Parameter Description
    Listener Name Enter a name for the listener.

    The name must be 2 to 128 characters in length, and can contain letters, digits, underscores (_), and hyphens (-). The name must start with a letter.

    Protocol Select the protocol of the listener.

    In this example, TCP is selected.

    Port Number Specify a port for the listener. The port is used to receive and forward requests to endpoints. Valid values: 1 to 65499.

    The value is set to 80 in this example.

    Client Affinity Specify whether to enable client affinity. If client affinity is enabled, requests from the same client can be directed to the same endpoint when the client accesses a stateful application.

    In this example, Source IP Address is selected.

  3. Click Next to configure an endpoint group.

Step 5: Configure an endpoint group

Each listener is associated with an endpoint group. You can associate an endpoint group with a listener by specifying the region to which you want to distribute network traffic. After you associate an endpoint group with a listener, traffic is distributed to the optimal endpoint in the associated endpoint group.

  1. On the Configure Endpoint Group wizard page, set the following parameters for the endpoint group:
    Parameter Description
    Endpoint Group Name Enter a name for the endpoint group.

    The name must be 2 to 128 characters in length, and can contain letters, digits, underscores (_), and hyphens (-). The name must start with a letter.

    Region Select the region to which the endpoint group belongs, which is the region to which the destination servers belong.

    In this example, US (Silicon Valley) is selected.

    Backend Service Specify whether the backend service is deployed on Alibaba Cloud.

    Off Alibaba Cloud is selected in this example.

    Preserve Client IP Specify whether to preserve client IP addresses. After the feature is enabled, backend servers can obtain source IP addresses of clients.

    In this example, this feature is disabled.

    Endpoint An endpoint serves as the destination that a client requests to access. Set the following parameters to configure an endpoint:
    • Backend Service Type: Select Custom IP Address from the drop-down list.
    • Backend Service: Enter the IP address of the backend service that you want to accelerate.
    • Weight: Specify a weight for the endpoint. Valid values: 0 to 255. GA routes traffic to endpoints based on the specified weights.
    Notice If you set the weight of an endpoint to 0, GA does not route network traffic to the endpoint. Proceed with caution.
  2. Click Next, confirm the configurations of the listener and endpoint, and then click Submit.

Step 6: Test the connectivity

To test the acceleration performance, perform the following steps:

  1. Open the CLI of an IPv6 client in the acceleration region. An IPv6 client in China (Hong Kong) is used in this example.
  2. Run the following command to test whether the IPv6 client can access IPv4 services:
    curl http://[<accelerated IP address assigned by GA>]
    Note A client that runs the Alibaba Cloud Linux 2 operating system is used in this example. The command that is used to verify the connectivity varies based on the operating system that you use. For more information, see the user guide of your operating system.
    The test result shows that the IPv6 client can access the IPv4 services deployed in the US (Silicon Valley) region. Access IPv4 services
  3. Run the following command to query the network latency:
    curl -o /dev/null -s -w "time_connect: %{time_connect}\ntime_starttransfer: %{time_starttransfer}\ntime_total: %{time_total}\n" -g "http[s]://<accelerated IP address assigned by GA>"
    where:
    • time_connect: the period of time that it takes to establish a TCP connection.
    • time_starttransfer: the start time of data transfer. It refers to the time that it takes for the backend server to send the first byte after the client sends a request.
    • time_total: the total connection time. It refers to the time that it takes for the backend server to respond after the client sends a request.
    The test result indicates that GA reduces network latency when the IPv6 client accesses the IPv4 services deployed in the US (Silicon Valley) region.
    Figure 1. The network latency of data transmission before GA is used
    The network latency of data transmission before GA is used
    Figure 2. The network latency of data transmission after GA is used
    The network latency of data transmission after GA is used
    Note The actual performance of the acceleration service provided by GA for accessing IPv4 services from IPv6 clients varies based on your workload.