Programs such as Solution Technology Integrators (STI), ISPN, SIP, and S+ are considered go-to-market benefits under the Cisco Developer Network umbrella. So if the Cisco Developer:
 
- Wants to resell a specific Cisco SKU for their own solution, there's STI
- Wants Cisco to resell their product by placement on the price list, there's S+
- Wants Cisco channel partners to be incentivized to sell their application with Cisco gear as part of a solution, there's SIP
- Wants to network with Cisco channel partners that focus on the same industry that they focus on, there's ISPN
 
Keep in mind that each of these programs has unique requirements. Furthermore, S+ is by invitation only.