LM N OP Q R ST U V W XY Z , ▁the ▁encryption ▁process ▁can ▁also ▁be ▁concept ual ized ▁as ▁finding , ▁for ▁each ▁letter , ▁the ▁intersection ▁of ▁the ▁row ▁containing ▁the ▁letter ▁to ▁be ▁encrypted ▁with ▁the ▁column ▁corresponding ▁to ▁the ▁current ▁letter ▁of ▁the ▁key . ▁The ▁letter ▁where ▁this ▁row ▁and ▁column ▁cross ▁is ▁the ▁ci pher text ▁letter . ▁ ▁Program matically , ▁the ▁ci pher ▁is ▁comput able , ▁assigning ▁, ▁then ▁the ▁encryption ▁process ▁is ▁. ▁Dec ryption ▁follows ▁the ▁same ▁process , ▁ex ch anging ▁ci pher text ▁and ▁plain text . ▁ ▁may ▁be ▁defined ▁as ▁the ▁value ▁of ▁a ▁letter ▁from ▁a ▁companion ▁ci pher text ▁in ▁a ▁running ▁key ▁ci pher , ▁a ▁constant ▁for ▁a ▁Ca esar ▁ci pher , ▁or ▁a ▁zero - based ▁counter ▁with ▁some ▁period ▁in ▁Tr ith em ius ' s ▁usage . ▁ ▁References ▁ ▁Cit ations ▁ ▁S ources ▁▁▁▁▁▁▁▁▁▁ ▁Category : Class ical ▁ci ph ers <0x0A> </s> ▁" Bal ab ar ath i " ▁Y ed ida ▁K ames w ara ▁R ao , ▁better ▁known ▁as ▁Radio ▁Ann ay ya , ▁was ▁a ▁freedom ▁f ighter ▁and ▁personal ▁secretary ▁for ▁" And h ra ▁K es ari " ▁Tang ut uri ▁P rak as am ▁P ant ulu . ▁He ▁was ▁born ▁on ▁September ▁ 1 3 , ▁ 1 9 1 3 . ▁ ▁From ▁ 1 9 3 6 - 1 9 4 5 ▁he ▁worked ▁as