UDP Multicast/Multicast Implementation steps

UDP Multicast

Implement the server to group the client to play (send data).

Implementation steps:

server.c

1. Create a server socket

#include <sys/types.h>

#include <sys/socket.h>

int socket (int domain, int type, int protocol); return Socket

2. Building the server address structure

struct sockaddr_in serveraddr;

#include <strings.h>

Bzero (&serveraddr, sizeof (SERVERADDR));

serveraddr.sin_family = af_inet;

SERVERADDR.SIN_ADDR.S_ADDR = htonl (Inaddr_any); Ip

Serveraddr.sin_port = htons (server_port);// Port

3. Binding Address

int bind (int sockfd, const struct SOCKADDR *addr,

Socklen_t Addrlen);

4. Construct the multicast attribute structure

struct IP_MREQN Group;

#include <arpa/inet.h>

Inet_pton (AF_INET,GROUP,&GROUP.IMR_MULTIADDR);// Set multicast address

Net_pton (Af_inet, "0.0.0.0", &group.imr_address);// set Local address

Group.imr_ifindex=if_nametoindex ("ent0");// set NIC interface

5. Set Multicast permissions and properties

SetSockOpt (Sockfd,ipproto_ip,ip_multicast_if,&group,

sizeof (group);// Set multicast permissions and Options

6. Set Client multicast address

struct sockaddr_in cliaddr;

Bzero (&cliaddr,sizeof (CLIADDR));

Cliaddr.sin_family=af_inet;

Inet_pton (AF_INET,GROUP,&CLIADDR.SIN_ADDR.S_ADDR);

Cliaddr.sin_port=htons (Client_port);

7. Send Data

SendTo (Sockfd,buf,strlen (BUF), 0, (structsockaddr*) &cliaddr,

sizeof (CLIADDR));// Send message to multicast address, return data size

Client.c

1. Create a client socket

2. Building the client address structure

3. Binding Address

4. Construct the multicast structure

5. Set Multicast permissions and properties

6. Receive Data

#include <sys/types.h>

#include <sys/socket.h>

Len=recvfrom (Confd,buf,sizeof (BUF), 0,null,0);// Receive data

UDP Multicast/Multicast Implementation steps