| Value | Meaning |
|---|---|
| SOCKETSOL_SOCKET | Socket level |
| IPProtocolType.IP | Internet Protocol version 4 level |
| ICMPProtocolType.ICMP | Internet Control Message Protocol level |
| IGMPProtocolType.IGMP | Internet Group Management Protocol level |
| GGPProtocolType.GGP | Gateway to Gateway Protocol level |
| TCPProtocolType.TCP | Transmission Control Protocol level |
| PUPProtocolType.PUP | PARC Universal Packet Protocol level |
| UDPProtocolType.UDP | User Datagram Protocol level |
| IDPProtocolType.IDP | Xerox NS protocol level |
| RAWProtocolType.RAW | Raw IP packet level |
| IPV6ProtocolType.IPV6 | Internet Protocol version 6 level |
The level at which a socket option is defined: