SMB is a network file sharing protocol that requires an open port on a computer or server to communicate with other systems. SMB ports are generally port numbers 139 and 445. Port 139 is used by SMB dialects that communicate over NetBIOS.
Contents
What is SMB port used for?
The SMB protocol enables “inter-process communication,” which is the protocol that allows applications and services on networked computers to talk to each other. SMB enables the core set of network services such as file, print, and device sharing.
How do I find my SMB port number?
To identify ports and network interfaces your Samba domain member is listening on, run: # netstat -tulpn | egrep “smbd|nmbd|winbind” tcp 0 0 127.0.
Is SMB port 445 TCP or UDP?
SMB is available directly over TCP (port 445) and over NetBIOS over TCP/IP (port 139). Other ports you may see connected with NetBIOS communications are port 137 (nbname) and port 138 (nbdatagram) over User Datagram Protocol.
What is an SMB connection?
The Server Message Block (SMB) is a network protocol that enables users to communicate with remote computers and servers — to use their resources or share, open, and edit files. It’s also referred to as the server/client protocol, as the server has a resource that it can share with the client.
What are ports 137 and 138 used for?
UDP ports 137 and 138 are used for local NetBIOS browser, naming, and lookup functions.
Is SMB still used?
The only versions of Windows that require SMB1 are end-of-support (EOS). By years! These are Windows Server 2003 (EOS July 2015), Windows 2000 Server (EOS July 2010), their client editions, and older. Samba and Linux distros like Ubuntu have retired SMB1 as well.
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.
Which port is DNS?
53
Default Port Numbers
| Port | IP | Protocol |
|---|---|---|
| 22 | TCP | SSH |
| 25 | TCP | SMTP |
| 53 | TCP & UDP | DNS |
| 80 | TCP | HTTP |
Which port is used for telnet?
23
The default port for Telnet client connections is 23; to change this default, enter a port number between 1024 and 32,767.
What is port 445 used for in Windows 10?
Port 445 and port 139 are Windows ports. Port 139 is used for Network Basic Input Output System (NetBIOS) name resolution and port 445 is used for Server Message Blocks (SMB). They all serve Windows File and Printer Sharing.You will lose browsing capabilities to networks past the intranet network as well.
Is SMB secure over Internet?
Most companies will not allow SMB outbound so it’s not going to work in a lot of places. If access to a file share is required, either use a VPN to connect to the network first or something like owncloud/nextcloud. Every service is secure over the internet, if you don’t think about “what could happen”.
Is port 445 open by default?
If the server has NBT enabled, it listens on UDP ports 137 and 138, and TCP ports 139 and 445.All four ports are open as default in all versions of Windows, including Windows 10 and Windows Server 2019.
Where is SMB used?
Over the years, SMB has been used primarily to connect Windows computers, although most other systems — such as Linux and macOS — also include client components for connecting to SMB resources. A group at IBM developed the SMB protocol in the 1980s.
How do I access my SMB server?
How to connect via SMB on a Windows machine:
- Make sure that your Windows computer has one or several shared folders.
- Open Documents on your iPad or iPhone and tap the Plus button > Add Connection .
- Select Windows SMB server.
- Put your Windows machine’s IP address or local hostname into the URL field.
What is SMB path?
Stands for “Server Message Block.” SMB is a network protocol used by Windows-based computers that allows systems within the same network to share files. It allows computers connected to the same network or domain to access files from other local computers as easily as if they were on the computer’s local hard drive.
What port is FTP?
port 21
FTP is an unusual service in that it utilizes two ports, a ‘data’ port and a ‘command’ port (also known as the control port). Traditionally these are port 21 for the command port and port 20 for the data port.
Is port 135 a NetBIOS?
NetBIOS provides three distinct services: Name service (NetBIOS-NS) for name registration and resolution via port 137.
Workgroup VS Domain.
| Port | Protocol | Service |
|---|---|---|
| 135 | TCP | MS-RPC endpoint mapper |
| 137 | UDP | NetBIOS Name Service |
| 138 | UDP | NetBIOS Datagram Service |
| 139 | TCP | NetBIOS Session Service |
What is the port 3389?
Remote Desktop Protocol
Remote Desktop Protocol (RDP) is a Microsoft proprietary protocol that enables remote connections to other computers, typically over TCP port 3389. It provides network access for a remote user over an encrypted channel.
Does Windows 10 use SMB?
SMB or Server Message Block Protocols are used to connect your computer to an external server. Windows 10 ships with support of these protocols but they are disabled in the OOBE. Currently, Windows 11/10 supports SMBv1, SMBv2, and SMBv3 as well.
Should I disable SMB?
It is recommended to disable SMB version 1 since it is outdated and uses technology that is almost 30 years old. Says Microsoft, when you use SMB1, you lose key protections offered by later SMB protocol versions like: Pre-authentication Integrity (SMB 3.1. 1+) – Protects against security downgrade attacks.