When deploying your RTP tag you may have noticed that there are four options in the Generate Tag window.
![RTP - Tag versions.png](https://nation.marketo.com/servlet/JiveServlet/downloadImage/102-3488-10-175490/799-539/RTP+-+Tag+versions.png)
The differences are subtle and technical, but below are the explanations of each version.
RTP Tag - CDN, Asynchronous (Recommended)
- "Asynchronous" means that the page won't wait for the RTP script to load before loading other page elements
- In the case that RTP is not available, the request will timeout after 2 seconds
- This tag imports the RTP JavaScript from a network of servers called a Content Delivery Network (CDN). This assures higher availability rates and better loading performance
RTP Tag - CDN, Synchronous (High Speed)
- "Synchronous" means that the RTP tag will load before any other elements on the page load
- Like the CDN, Asynchronous tag, this tag makes use of a CDN
- The "High Speed" does not actually mean the script loads faster, it only means that the page won't load before the RTP script completely loaded
RTP Tag – Asynchronous
- Like the CDN, Asynchronous tag, the page loads other page elements while the tag is loading
- This tag Imports the RTP JavaScript directly from Marketo servers.
- In the case that RTP is not available the request will timeout after 2 seconds
RTP Tag – Synchronous
- Like the CDN, Synchronous tag, the page will not load while other page elements are loading
- This tag Imports the RTP JavaScript directly from Marketo servers