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Torch Object Storage

Working with buckets

Transfer acceleration

The transfer acceleration feature utilizes the globally distributed nodes and the backbone network of Volcano Engine. It uses intelligent routing resolution technology to process requests from the nearest available locations. Combined with optimized network transmission protocols, it provides a secure, high-quality, end-to-end network acceleration solution for TOS users. This topic covers use cases, notes, billing notes, and the steps for enabling and using the feature.

Use cases

Cross-border transfer of training dataset

Companies engaged in AI training often have computing resources and datasets located far apart, which leads to slow network transfer of datasets. Enabling transfer acceleration can greatly increase the speed of large-scale, cross-border data transfers.

Data transfer under poor network conditions

As mobile internet technology has evolved, the use of mobile network communication technologies to access the internet has grown. However, users often cannot maintain optimal network performance in areas with poor base station coverage, on transportation such as high-speed trains and subways, and in harsh environments such as mountains and deserts. The transfer acceleration feature uses optimized network transmission protocols to provide users with relatively smooth upload and download experiences under poor network conditions.

If your business primarily targets mobile internet users, using the transfer acceleration feature can give your application a more competitive edge.

Long-distance transfer of static data

If your users are located across the country, you can use the transfer acceleration feature to enhance their experience with long-distance network access. This feature is useful for activities such as downloading game installation packages, uploading and downloading photo albums, and uploading and downloading files to a cloud drive.

Billing notes

Different charges apply when you use the transfer acceleration feature, depending on the scenario. Common scenarios are explained below:

Use cases	Billable item
Uploading objects	You are charged for requests and transfer acceleration (inbound traffic).
Downloading objects	You are charged for requests, outbound traffic over the public network, and transfer acceleration (outbound traffic).
Replication between the Chinese mainland and other locations	You are charged for requests, cross-region replication traffic (source bucket), and transfer acceleration (outbound traffic).

For transfer acceleration pricing, see Transfer acceleration.

Notes

Category	Considerations
Billing	Fees are only charged when the transfer acceleration feature is used. Enabling the feature without using it will not incur any charges.
Permissions	Only the bucket owner or a user with the "tos:PutBucketTransferAcceleration" permission can configure transfer acceleration. For more information, see Configuring IAM policies.
Effective time	After you enable or disable transfer acceleration, it may take up to 30 minutes for the changes to take effect.
Logging	To ensure data transfer security, the transfer acceleration feature may use the HTTPS protocol, even if the client accesses TOS via HTTP. Logs may show HTTPS instead of HTTP.
Network	Transfer acceleration is compatible with public networks but not private networks. Transfer acceleration only supports the IPv4 protocol and does not support dual-stack. The default bandwidth limit is 5 Gbps. Submit a ticket if you need more bandwidth.
Domain names	After enabling transfer acceleration, you can access TOS through two types of domain names. Only transfer acceleration domain names provide acceleration benefits. The specific domain formats are as follows: Default domain: <bucketname>.tos-<Region>.volces.com Transfer acceleration domain: <bucketname>.tos-accelerate.volces.com and <bucketname>.tos-s3-accelerate.volces.com Access to TOS will fail if you attempt to use the transfer acceleration domain names without enabling the transfer acceleration feature.
Availability	Transfer acceleration is not supported for ListBuckets, CopyObject, and same-region replication operations. Transfer acceleration is only available for replication between regions inside and outside of the Chinese mainland. Once enabled for such scenarios, you cannot disable transfer acceleration. Transfer acceleration is not available for replication between regions within the Chinese mainland.

Enabling transfer acceleration

In the left navigation pane, click Buckets. In the Buckets list, click the bucket you want to manage.

In the left navigation pane, select Domain name and transfer acceleration > Transfer acceleration.

On the Transfer acceleration page, click Edit. Then, click Enable and Select.

tip

If your bucket is located in China (Hong Kong) or Asia Pacific (Johor), you must read and check the box for Compliance commitment.

In the Make sure to turn on transfer acceleration dialog box, click Save.

Transfer acceleration takes effect globally within 30 minutes of being enabled.

tip

To disable transfer acceleration, navigate to the Transfer acceleration page, and click Edit. Then, click Close and Select. Finally, click Save in the box that appears.

Using transfer acceleration

The default domain names for transfer acceleration are tos-accelerate.volces.com and tos-s3-accelerate.volces.com. After enabling transfer acceleration, you can also obtain these domain names on the Transfer acceleration page. You can then use these domain names to access TOS.

API

SDK

tosutil

Other browsers

To speed up data transfers when accessing TOS via APIs, replace the domain in the Host request with the transfer acceleration domain name. The following example uses the GetObject operation to illustrate this process.

To speed up data transfers when accessing TOS via SDKs, replace the endpoint in each language with the transfer acceleration domain name. The following example shows how to upload a local file using Go SDK. For more information, see SDK overview.

Testing transfer acceleration

You can use the network speed tool to verify if transfer acceleration is working as expected. Specifically, you can use the tool to compare the speeds of accelerated and non-accelerated transfers in a given region and measure the impact of transfer acceleration.

In the left navigation pane, click Network speed tool.

Select the region(s) you want to test and click Detect immediately.

tip

You can select multiple regions and test transfer speeds simultaneously from the client to each region.

The speed test is complete when the Velocity state changes from Detecting to Success. Then, the tool page shows the upload and download speeds between the client and TOS, both with and without transfer acceleration enabled.

Observability

Log analysis

Transfer acceleration traffic statistics

Logs record access requests to TOS. When the log field RequestSourceType is accelerate, it indicates that the request is for transfer acceleration. You can use this field to query the request time, source IP address, and requested object key. For more information, see Log analysis.

In the left navigation pane, click Buckets. In the Buckets list, click the bucket you want to manage.

In the left navigation pane, click Logging.

On the Logging page, click Edit under the Log analysis tab. Then, toggle the Current status switch on to enable the feature, and click Select.

On the Search Analysis tab, set the time range for the query, enter RequestSourceType:accelerate in the search box, and click Search.

On the Raw log tab, view the log details related to transfer acceleration requests, including request time, source IP address, and account ID.

FAQ

How does the transfer acceleration feature differ from using Volcano Engine Global Accelerator with TOS's default domains?

The transfer acceleration feature offers simpler and more flexible operations than using the Volcano Engine Global Accelerator with TOS's default domains. You can increase transfer speeds with one click, without preparing domain names in advance.

Can the transfer acceleration feature be used with Volcano Engine Content Delivery Network (CDN) for downloads?

Yes. Combining the transfer acceleration feature with CDN improves the speed and success rate of back-to-origin requests.

Last updated: 2026.07.24 11:20:32