Identity based infrastructure allows the public keyof a user to be derived easily from a predefined aspect of theirknown identity such as a phone number, passport number orother universally unique identifier. Recently, H¨olbl and Welzerhave proposed an identity-based key establishment protocol.However, this protocol is found to be vulnerable to man-inthe-middle attacks and impersonation attacks. In this paper,we propose multi-channel identity based protocols for wirelesspersonal area networks which can eliminate these attacks.These protocols alleviate the certificate overhead by using apublic key infrastructure which is suitable for wireless personalarea networks.