/// <summary>
        /// Gets the standard subject claims.
        /// </summary>
        /// <param name="subject">The subject.</param>
        /// <returns>A list of standard claims</returns>
        protected virtual IEnumerable<Claim> GetStandardSubjectClaims(ClaimsPrincipal subject)
        {
            var claims = new List<Claim>
            {
                new Claim(Constants.ClaimTypes.Subject, subject.GetSubjectId()),
                new Claim(Constants.ClaimTypes.AuthenticationMethod, subject.GetAuthenticationMethod()),
                new Claim(Constants.ClaimTypes.AuthenticationTime, subject.GetAuthenticationTimeEpoch().ToString(), ClaimValueTypes.Integer),
                new Claim(Constants.ClaimTypes.IdentityProvider, subject.GetIdentityProvider()),
            };

            return claims;
        }