Securing communication sessions between networked embedded systems is a major challenge that needs to be addressed as an increasing number of such systems become Internet-enabled. Securely and quickly establishing a session key between communicating nodes in a network requires authentication of node identities. In this paper, we propose a simple elliptic-curve based key negotiation protocol suitable for fully hardware implementation as a protocol on chip (PoC). The protocol uses the elliptic curve variants of both the Diffie Hellmann exchange and the Digital Signature Algorithm. Timing results demonstrate that an endto- end protocol run can be performed in as little as 28ms on a 25MHz clock, which is several times faster than previous microprocessor-based implementations of similar protocols. The results indicate that session keys can thereby have shorter lifetimes, since there is little computational overhead in re-generating them, thus enhancing overall security of the networked embedded systems.