If you distribute your Digital Assets with the legacy public APIs, you are leaving speed, quality, and modern formats on the table. AI MediaBoost's Content Delivery APIs are the current delivery standard, and the automatic redirect mechanism allows you to migrate while preserving the organic ranking you have built on existing links.

This guide explains what changes in URLs, how to convert the links you have already published, and the order in which to carry out the steps to avoid penalizing your channels during the transition.

Public APIs and Content Delivery APIs: what changes in the URL

The two APIs deliver the same assets with different URL structures. The legacy APIs carry all rendering options in the path, while the new ones expose them as query parameters.

Legacy image URL:

https://<clientId>-cdn.thron.com/delivery/public/image/<clientId>/<id>/<pkey>/<preset>/<divArea>/<prettyName>

URL with Content Delivery APIs:

https://<clientId>-cdn.thron.com/api/v1/content-delivery/shares/<pkey>/contents/<id>/image/<dynamicSeoSuffix>

Three structural differences to keep in mind before starting the conversion:

• The pKey moves from the end of the path to the shares/ segment, right after the API root.

• The delivery format is no longer specified: THRON always delivers the best format for the requesting browser.

• The segment following contents/<id> declares the resource type you want to retrieve: image, video/source, pdf, audio/source, pagelet, thumbnail, or original.

Why migrate: performance, quality, security, and formats

Moving to the new APIs is not just a cosmetic change. Content Delivery APIs are technically superior on four fronts:

• Performance: faster delivery tailored to the requesting browser.

• Quality: optimized asset management, with higher quality for the same file size.

• Security: safer delivery mechanisms.

• Formats: support for all new formats, which legacy APIs do not handle.

These four benefits alone justify the migration. If you worry that changing URLs will cause you to lose the ranking you built over time, THRON provides a dedicated mechanism to transfer Link Equity from legacy THRON links to new ones.

Link Juice: what it is and why you don't lose it by migrating

Link Juice, or Link Equity, is the value of authority that a link passes from one page to another. When a user clicks on an image or link and is redirected to a website, search engines recognize that link as valuable: the more interactions it receives over time, the more ranking it acquires, and the higher it appears in search results.

A concrete example: a user searches for a product on Google Images, clicks on the photo you published, and lands on your site. Repeated over time, this interaction increases the ranking of that specific link.

The automatic redirect mechanism transfers the Link Juice accumulated by old URLs to new ones, without any loss of ranking. It is not a mandatory migration step: request it if the organic ranking of your links is an asset you want to preserve.

Automatic redirect: how it works and when to enable it

The automatic redirect mechanism links legacy public URLs to the new Content Delivery API. Crawlers recognize the new URLs as equivalent to the old ones, transfer the accumulated trust, and maintain ranking.

Three conditions determine the outcome:

• Same pKey: the redirect only works if you continue to use the same pKey in the new API. It is not possible to redirect an old pKey to multiple different pKeys. If you need to change your pKey, discuss it with your THRON account manager before starting migration.

• Automatic parameter remapping: correspondence between old and new parameters is handled automatically by the redirect mechanism.

Which links THRON can cover and which it cannot

The transfer mechanism works on links served from the THRON domain: that is where THRON can link old and new URLs and transfer the accumulated ranking.

If you currently distribute your assets from another platform, those links are not under THRON's control and the transfer cannot start from here. In that case, redirection must be configured by whoever manages those domains today—your current provider.

Who does what in migration

In summary: choosing what to migrate is up to you or your integrator. Once completed, THRON maintains the SEO connection between old and new via the redirect mechanism. Then it will be up to you again to migrate from old to new APIs.
If you need help, you can always contact support@thron.com

URL re-mapping: how existing link conversion works

Converting from the legacy delivery/public system to the new api/v1/content-delivery follows different rules for each asset type. The following tables show the correspondence between parameters.

Images

If your legacy URLs use percentage values for cropping, convert them to pixels with this formula:

cx = int(round(w * (cropX / 100)))
cy = int(round(h * (cropY / 100)))
cw = int(round(w * (cropW / 100)))
ch = int(round(h * (cropH / 100)))

Conversion example:

• Legacy URL: https://lago-cdn.thron.com/delivery/public/image/lago/5aa99e51-75a7-4c04-9801-094ac1de88f2/sqVrcnw/std/640x0/image.webp?quality=70

• New URL: https://lago-cdn.thron.com/api/v1/content-delivery/shares/sqVrcnw/contents/5aa99e51-75a7-4c04-9801-094ac1de88f2/image/image.webp?w=640&q=70

Video

The new APIs replace fixed channels in the channelType parameter with maxH, which defines maximum delivery height. To convert a video URL, retrieve the height from the legacy asset details and match it with the corresponding value of maxH.

• Legacy URL: https://lago-cdn.thron.com/delivery/public/video/lago/eb50098e-a5da-433d-8b72-970f8a0deefa/wddU3re/WEBHD/qvideo1

• New URL: https://lago-cdn.thron.com/api/v1/content-delivery/shares/wddU3re/contents/eb50098e-a5da-433d-8b72-970f8a0deefa/video/source/video?maxH=1080

The value you can request with maxH and available codecs depend on the AI MediaBoost profile active in your contract.

Both profiles deliver via progressive download and HTTP streaming. With the PRO profile, delivery tops out at Full HD: a higher maxH value will not produce a 4K video.

Documents and original files

Documents are served as PDF via the pdf segment. To download the original file, whatever its type, use the original segment with the download=true parameter.

• Legacy URL: https://lago-cdn.thron.com/delivery/public/document/lago/f409aaac-d4e0-41f9-9b97-c9178f6e2da4/hiz3eq/WEB/regolamento.pdf

• New URL: https://lago-cdn.thron.com/api/v1/content-delivery/shares/hiz3eq/contents/f409aaac-d4e0-41f9-9b97-c9178f6e2da4/pdf/regolamento.pdf

Audio, pagelets, and thumbnails

For audio and pagelets, conversion is direct: segments become audio/source and pagelet, while the path parameters channelType and lcid have been removed.

Thumbnails instead have a dedicated behavior: they only accept w, h, and maxAge, and no longer accept image editing parameters. The image is delivered in the best available format, resized and, when necessary, center-cropped.

Recommended configuration

Follow the steps in this order to avoid penalizing your channels during transition:

1. Activate the Custom Domain.

2. Create an inventory of the pKeys involved and share them with THRON.

3. For legacy public URLs, ask THRON to always return the new delivery using Link Juice applied to your pKeys, injecting a redirect behavior that preserves your ranking.

4. Set up 301 redirects from legacy URLs to the new ones; legacy routes will automatically return a 301 redirecting to the new route that delivers content, with parameters mapped automatically between the old and new APIs.

301 redirect example:

• From: https://lago-cdn.thron.com/delivery/public/image/lago/20212d26-2f05-4ec1-8e09-87892e2572a3/sqVrcnw/std/520x568/fauteuil.webp?quality=70

• To: https://lago-cdn.thron.com/api/v1/content-delivery/shares/sqVrcnw/contents/20212d26-2f05-4ec1-8e09-87892e2572a3/image/fauteuil.webp?ch=2915&cw=2670&q=70

Current limitations of Link Juice transfer

Link Juice transfer is already available for all asset types, with two exceptions:

• Thumbnails: deep dives are underway to ensure optimal integration with Content Delivery APIs.

• Audio: work can be initiated upon request; speak with your THRON account manager.

Custom Domain: the advantage unlocked with migration

During or after migration, activate a Custom Domain: your assets are served from your own subdomain, such as assets.yourdomain.com, instead of the THRON domain. The benefit is both SEO—consolidating traffic and backlinks on a single domain—and brand consistency, keeping URLs aligned with your identity wherever they are shared.

Custom Domain is only available on Content Delivery APIs and is not supported on legacy public APIs. To activate it, contact your THRON account manager.

## Additional articles
- 
AI MediaBoost Custom Domain: what it is and how to activate it
- 
The pKey: what it is and how to manage it
- 
Integrate THRON into an external channel: developer guide
- 
AI MediaBoost Image Editing: what it does and how to use it
- 
Embed a Digital Asset into an external website or web page

Need help?

For technical issues, contact support@thron.com