Modbus TCP to Ethernet IP via a PC

I am looking for an application that converts Modbus TCP to Ethernet IP on a PC. Basically I have one device hooked up to a PC speaking Modbus TCP, and I have an Ethernet IP network hanging off a different port on the same PC. It seems silly to buy and configure additional hardware to do the protocol change, surely the PC has enough power to translate this message. Is there an application that can do this?

kepware has this capability, but it would be cheaper to use a digi one iap.

Thanks, Yes it is quite expensive.

What features do you want to implement on EtherNet/IP; do you want a tag server, or an I/O server, or a PCCC server ? Or something else ?

I agree that this is very typically done with hardware. The Digi One IAP, the Red Lion Data Station Plus, and the HMS Communicator are the first few that come to mind.