const pk: Function;
secret sk: Function;
inversekeys (pk,sk);

protocol nsl7(I,R)
{
	role R
	{
		var ni;
		const nr;

		read_1(I,R, {I,ni}pk(R) );
		send_2(R,I, {ni,nr,R}pk(I) );
		read_3(I,R, {nr}pk(R) );
		claim_4(I,Secret,nr,ni);
	}
}

const Alice,Bob;

run nsl7.R(Alice,Bob);
run nsl7.R(Alice,Bob);