# open62541 vs Prosys OPC UA Gateway

Source: https://listme.name/compare/open62541-vs-prosys-opc-ua-gateway
Framed by the ranking: https://listme.name/best/opc-and-industrial-connectivity-software

| | open62541 | Prosys OPC UA Gateway |
|---|---|---|
| Score | 77.5 | 79.0 |
| Rank | #8 | #6 |
| Price | Free and open source | Paid |
| Best for | Developers building OPC UA servers and clients in C | Migrating legacy COM OPC servers to OPC UA |
| Protocols | OPC UA (IEC 62541) | OPC DA 2/3, OPC AE, OPC HDA to OPC UA |
| License model | Open source under MPL-2.0 | Licensed; price list on the site |
| Trial | Not needed; source is free | Trial offered |

Free MPL-2.0 OPC UA library in C99 that runs on Windows, Linux, RTOS and Android. It suits developers who write their own servers and clients, and it is not a configurable gateway or a client tool. Wraps classic COM OPC DA, AE and HDA servers as OPC UA servers, with runtime connection changes. It is a 32-bit and 64-bit Windows application, and pricing sits in a separate price list.