Take a look at the following resources:

• Visit the documentation of the net standard Go package, which can be found at https://golang.org/pkg/net/. This is one of the biggest documentation found in the Go documentation.
• Although this book talked about RPC, it did not talk about gRPC, which is an open source, high-performance RPC framework. A package with the Go language implementation of gRPC can be found at https://github.com/grpc/grpc-go.
• The ICMP protocol for IPv4 is defined in RFC 792. It can be found in many places, including https://tools.ietf.org/html/rfc792.
• WebSocket is a protocol for two-way communication between a client and a remote host. There is a WebSocket implementation for Go at https://github.com/gorilla/websocket. You can learn more about WebSocket at http://www.rfc-editor.org/rfc/rfc6455.txt.
• If you are really into network programming and you want to be able to work with RAW TCP packets, you mind find interesting and helpful information and tools in the gopacket library, which can be found at https://github.com/google/gopacket.
• The raw package, which is located at https://github.com/mdlayher/raw allows you to read and write data at the device driver level for a network device.