Installing : Installing System Architect : Planning the installation : Ports and protocols for the SQL Server
  
Ports and protocols for the SQL Server
The following are supported ports and protocols for the using the SQL Server.
The Microsoft SQL Server is a Winsock application that communicates over TCP/IP using the sockets network library and listens for incoming connections on a particular port. The default port for is 1433. The port does not need to be 1433, but 1433 is the official Internet Assigned Number Authority (IANA) socket number for Microsoft SQL Server. For more information, see:
http://support.microsoft.com/kb/287932/
You can also use the Named Pipes protocol, but the default is TCP/IP.