What is TCP 445 used for?

Port 445 is a traditional Microsoft networking port with tie-ins to the original NetBIOS service found in earlier versions of Windows OSes. Today, port 445 is used by Microsoft Directory Services for Active Directory (AD) and for the Server Message Block (SMB) protocol over TCP/IP.

What is port 445 TCP?

TCP port 445 is used for direct TCP/IP MS Networking access without the need for a NetBIOS layer. This service is only implemented in the more recent verions Windows starting with Windows 2000 and Windows XP. The SMB (Server Message Block) protocol is used among other things for file sharing in Windows NT/2K/XP.

What are ports 139 and 445 used for?

Port 139 is used by SMB dialects that communicate over NetBIOS. It’s a transport layer protocol designed to use in Windows operating systems over a network. Port 445 is used by newer versions of SMB (after Windows 2000) on top of a TCP stack, allowing SMB to communicate over the Internet.

Is SMB port 445 secure?

blocking all versions of SMB at the network boundary by blocking TCP port 445 with related protocols on UDP ports 137-138 and TCP port 139, for all boundary devices. …

Is port 139 needed for SMB?

What Are Ports 139 And 445? SMB has always been a network file sharing protocol. As such, SMB requires network ports on a computer or server to enable communication to other systems. SMB uses either IP port 139 or 445.

What is the difference between port 139 and 445?

Why is port 139 open?

If you are on Windows-based network that is running NetBios, it is perfectly normal to have port 139 open in order to facilitate that protocol. If you are not on a network using NetBios, there is no reason to have that port open.

What’s the difference between port 139 and port 445?

Port 139 is used by SMB dialects that communicate over NetBIOS. It’s a transport layer protocol designed to use in Windows operating systems over a network. Port 445 is used by newer versions of SMB (after Windows 2000) on top of a TCP stack, allowing SMB to communicate over the Internet.

Is there a port 445 for UDP and TCP?

In Windows 2000, Microsoft has created a new transport for SMB over TCP and UDP on port 445. This replaces the older implementation that was over ports 137, 138, 139. Your Pix should be by default be blocking these inbound. If you block these outbound as well, you will loose browsing capabilities to networks past the internat network.

Why is my computer not connecting to ports 139 and 445?

The patching software states that this means: The computer isn’t listening or it’s blocking access to TCP ports 139 and 445. If I log on locally or remote into this server, I can not “telnet 127.0.0.1 139”. I receive “Connecting to 127.0.0.1….Could not open connection to the host, on port 139: Connect failed. I can telnet to 445.

What’s the difference between ports 139 and 445 in SMB?

SMB ports are generally port numbers 139 and 445. Port 139: Used by SMB dialects that communicate over NetBIOS, a transport layer protocol designed to use in Windows operating systems over a network. Port 445: Used by newer versions of SMB (after Windows 2000) on top of a TCP stack, allowing SMB to communicate over the Internet.