Abstract—The evolutions in space technologies are facilitating the realization of scientific deep space missions. Unpredictable link reliability, network connectivity, large round trip times (RTT) and wide variations in transmission latencies are characteristics of such networks. This could pose significant problems for deep space missions. Also the present day Internet protocols are ill suited for the purpose of deep space missions as performance deteriorates quickly under the above above-mentioned conditions. The work undertaken ndertaken presents a delay-tolerant network (DTN) communication system architectural design, design and modeling of DTN Bundle Protocol and Characterization, Analysis and Performance evaluation of such networks.