Hi,
Thank you for posting in Symantec community.
I would be glad to answer your query.
Refer the following screenshot to understand which ports are used for what purpose during SEPM install.
You can change the ports if there is any conflict.
If looking for SEPM install guide then can refer the following articles.
SEPM 12.1 Fresh install with Embedded database - graphical overview
http://bit.ly/KUWxaS
SEPM 12.1 Fresh install with SQL database - graphical overview
http://bit.ly/JiDgpM