"can someone explain how software distribution like this works....

"can someone explain how software distribution like this works. Autodesk give a licence to DD to sell subscriptions to onsellers (cadgroup, a2ktechnologies, viewlistic) to sell to end user? And it's better than the end user buying direct from the Autodesk website?"

Enterprise software is very commonly sold via Distribution through to a reseller channel. Many reasons include:
* Discounts / special bid pricing on projects dynamic to each end user (dynamic pricing to allow for customised pricing)
* Resellers get out and sell the technology and then integrate that technology so it works with other systems
* Credit terms
* SaaS billing with other licenses
* Reseller & Distributor can manage the license as needed (upgrades, cross grades, downgrades, 'special packages')
* Reseller and Distribution will often handle L1 support
* Rebates + other incentives
* Distribution + Reseller will 'protect' the end user from other competitors i.e a relationship is built from end user to reseller to Distributor to Vendor
* Distribution can handle bulk training to Resellers > end users
* Some vendors don't have a true in-country presence for business purposes and the Distributor therefore becomes the importer on record
* Small Vendors may have zero local presence and therefore rely upon the Distribution arm to grow their channel
* Revenue recognition timing points

The list goes on and will vary for each Vendor and their needs.