Answer:
They are set up manually
Step-by-step explanation:
BGP neighbor relationships formed "They are set up manually."
This is explained between when the BGP developed a close to a neighbor with other BGP routers, the BGP neighbor is then fully made manually with the help of TCP port 179 to connect and form the relationship between the BGP neighbor, this is then followed up through the interaction of any routing data between them.
For BGP neighbors relationship to become established it succeeds through various phases, which are:
1. Idle
2. Connect
3. Active
4. OpenSent
5. OpenConfirm
6. Established