Connect Four on 6 high, 7 wide grid, there are 4,531,985,219,092 positions for all game boards populated with 0 to 42 pieces. The game was first solved by James Dow Allen (October 1, 1988), and independently by Victor Allis (October 16, 1988). Allis describes a knowledge-based approach, with nine strategies, as a solution for Connect Four. Allen also describes winning strategies in his analysis of the game. At the time of the initial solutions for Connect Four, brute-force analysis was not deemed feasible given the game's complexity and the computer technology available at the time. Connect Four has since been solved with
CT Connect CSTA. The CSTA standard specifies a call model (that is, how parties participate in a call and the steps a call goes through as it proceeds) and a set of messages that can be exchanged between a telephone system and a computer system. When both telephone systems and computer systems implement the CSTA standard, a customer can choose freely among competing products with confidence that they will interoperate. As described more fully below, the CT Connect development team participated in the definition of CSTA. CT Connect and its predecessor, Digital Equipment's Computer Integrated Telephony product line, implement the CSTA call