Fundamental principles of high-frequency chaos generation and synchronization in Er-doped fiber ring lasers are analyzed. The experimental configuration for generating wavelength-tunable chaos is proposed, and high-frequency chaotic lasers at different wavelengths are generated. Synchronization between the chaos generated in the receiver laser and the chaos transmitted over 1 km that is generated in the transmitter laser are achieved, which paves the way for constructing the high speed secure chaos communication network.