The following table contains a list of available TCP/IP API modules. All support the Domain Names Services (DNS) GetHostByName and GetHostByAddr.
| API | Interface Loaded | GetHostByName | GetHostByAddr | 
|---|---|---|---|
| BS2 | BS2000/OSD interface NWTCPBS2 | Yes | Yes | 
| CNS | z/VSE interface NWTCPCNS | Yes | Yes | 
| EZA | z/VSE interface NWTCPEZA | Yes | Yes | 
| HPS | IBM interface NWTCPHPS (High Performance Native Sockets) | Yes | Yes | 
| OES | IBM OpenEdition sockets interface NWTCPOES | Yes | Yes |