Question: Define AND describe 2 technical features of 2G GSM (ie, the initial version of GSM, NOT how it evolved into 3G) and 2G CDMA (the initial version of CDMA, ie, IS-95) cellular systems that are similar or the same, and two technical areas where the features of the two are different, with details on each of the 2 technical similarities and the 2 technical differences. First describe the 2 technical similarities, then the 2 different technical features, . [Do NOT say that the two provide cellular service and that's a similarity, the intent here is to describe similarities and differences on their technical aspects such as features and/or technologies they use. Differences in their market penetration is also NOT part of the desired answers here]