**Abstract:**
Diffie Hellman key exchange algorithm was proposed in 1976. Extension of this algorithm is done for multiple participants. The number of exponentiations will vary by N. If large number of participants is involved then it becomes complicated. Here we reduce the complexity and increase the speed by making use of divide and conquer technique. It divides the total number of participants into smaller groups and applies algorithm on them independently. There are log2N+1 exponentiations obtained which are less compared to N and makes the key exchange simpler. Software implementation of extension of this algorithm is done using MATLAB. Further hardware implementation is carried out by making use of a DSP processor.

**Keywords:**
Diffie Hellman key exchange algorithm.