**What is IP transit circuit?**

IP Transit is a service by which networks have access to the rest of the Internet via BGP. ... In contrast to services based on default routing, such as dedicated Internet access (DIA) and IP Connect, IP Transit affords larger networks greater routing flexibility and control.

https://www.genesisadaptive.com/blog/what-is-ip-transit

https://www.slideshare.net/bdnog/ip-transit-simple-math-simple-calculation