Digital Backward Propagation (DBP) technique is gaining imporance as it allwos the joint electronic compensation of linear and non-linear impairments in the optical fiber. Effect of root raised cosine (RRC) pulse shapng on the performance of DBP algorithm is investigated for 112 Gbits/sec DP-QPSK transmission system and performance of DBP for non return to zero (NRZ), return to zero (RZ) and RRC pulse shape is compared. A new concept of optizmized RRC pulses is proposed. It is also shown that the optimized-RRC pulses are more tolerant to the non-linear effects as compared to simple RRC pulses. In additon to this, a comparative study is also performed for different fiber types and multi-span DBP which shows 80% reduction in computational efforts of DBP algorithm. From these results somple model of DBP is derived and the performance of different transmission scenarios is also investigated. These investigations show the adaptivity of DBP algorithm to the misinformation about transmission link design parameters specially the errors in total transmission length.