计算机网络
ping
基于 ICMP 协议,通过发送 ICMP ECHO_REQUEST packets 给指定网络,通过目标返回的 ICMP ECHO_RESPONSE 判断 IP 可不可达了
graph TD;
client--> |发送ICMP PACKET| target(目标服务器)
target --> |收到后发送响应报文ICMP RESPONSE| client
TCP
SOCKET
建立过程
graph TD;
client-->C_socket
C_socket-->C_connect
server-->socketServer(socket)
socketServer-->bind
bind-->listen
listen-->accept
accept-->|等待和client的connect建立成功| read
C_connect-->C_write
C_write-->|发送请求数据给服务器|read
read-->|服务器处理请求|writeServer(write)
writeServer-->read
writeServer-->|服务器返回数据给client| readClient
C_write-->readClient(C_read)
readClient-->C_write
readClient-->C_close
writeServer-->readEnd
C_close-->|EOF 通知服务器|readEnd(read)
readEnd-->closeServer(close)