I have set up a shared folder to my linux maschine . It runs over the samba server present in Linux . the only problem is that this protocol in not encrypted and I do not feel comfortable with that . Is there any way to encrypt the smb traffic ( without ssh tunnel or VPN server ) .
You cannot encrypt data if you're using the 2.XX family of SMB dialects. Encryption support was brought in from 3.XX. You can enable signing to see if your packets were tampered with, though.
So to get encryption working just change the dialect to SMB3+ and smb encrypt = required as @AlexP pointed out.