Common Internet File System (CIFS)
CIFS (Common Internet File System) is Microsoft’s renamed and extended version of SMB 1.0, introduced in 1996. The name “CIFS” was an attempt to position the protocol as an internet standard alongside protocols like HTTP and FTP.
CIFS vs SMB
While the terms are sometimes used interchangeably, there is an important distinction:
| Aspect | CIFS | SMB |
|---|---|---|
| Protocol version | SMB 1.0 only | SMB 1.0, 2.0, 2.1, 3.0, 3.1.1 |
| Status | Deprecated | Actively developed |
| Performance | Chatty, high latency | Efficient (SMB 2.0+) |
| Security | Weak (no encryption) | Strong (SMB 3.0+ encryption) |
| Modern usage | Legacy only | Current standard |
CIFS is deprecated
CIFS refers specifically to SMB 1.0, which is deprecated and carries serious security vulnerabilities (including the EternalBlue exploit). Always use SMB 3.x in modern environments. See Server Message Block (SMB) for details on modern SMB versions.
The Linux cifs Mount Type
On Linux, the mount -t cifs command and the cifs-utils package support modern SMB versions despite the legacy name. The vers= mount option controls which SMB version is negotiated:
# This uses SMB 3.1.1 despite the "cifs" type name
sudo mount -t cifs //server/share /mnt/share -o vers=3.1.1,username=userThe naming is a historical artifact — the Linux kernel module was written when “CIFS” was the common term for the protocol.
Further Reading
See Server Message Block (SMB) for comprehensive coverage of:
- SMB protocol versions 1.0 through 3.1.1
- Samba configuration and Active Directory integration
- Security hardening and best practices
- Troubleshooting common issues