The defensive trio have all been linked with moves elsewhere with the Welsh outfit already rejecting a £1million approach from Ipswich for centre-back Johnson.
Ridsdale told the South Wales Echo: "I do not want to lose any players. We are looking to build on what we have now.
"I have met with Roger's agent and Kevin's too and I will be meeting with Glenn's agent this week.
"We believe we have some lucrative packages to offer them and are very optimistic they will commit their futures to Cardiff City."