tse transmission get hanged in TCP protocal

Here is my changed simple_socket_sever.c

# include <stdio.h>
# include <string.h>
# include <ctype.h> 
# include "includes.h"
# include "simple_socket_server.h"                                                                    
# include "alt_error_handler.h"
# include "ipport.h"
# include "tcpport.h"
 
void sss_reset_connection(SSSConn* conn)
{
  memset(conn, 0, sizeof(SSSConn));
  conn->fd = -1;
  conn->state = READY;
  conn->rx_wr_pos = conn->rx_buffer;
  conn->rx_rd_pos = conn->rx_buffer;
  return;
}
void sss_handle_accept(int listen_socket, SSSConn* conn)
{
  int                 socket, len;
  struct sockaddr_in  incoming_addr;
  alt_u8 sendBuf;
  alt_u8 *send_ptr = sendBuf;
  len = sizeof(incoming_addr);
  if ((conn)->fd == -1)
  {
     if((socket=accept(listen_socket,(struct sockaddr*)&incoming_addr,&len))<0)
     {
         alt_NetworkErrorHandler(EXPANDED_DIAGNOSIS_CODE,
                                 " accept failed");
     }
     else
     {
        (conn)->fd = socket;
        //sss_send_menu(conn);
        send_ptr += sprintf(send_ptr,"Connected OK!\n\r"); 
        send_ptr += sprintf(send_ptr,inet_ntoa(incoming_addr.sin_addr));
        send_ptr += sprintf(send_ptr,"\n\r");
        send(conn->fd, sendBuf, send_ptr-sendBuf, 0);
        printf(" accepted connection request from %s\n",
               inet_ntoa(incoming_addr.sin_addr));
     }
  }
  else
  {
    printf(" rejected connection request from %s\n",
           inet_ntoa(incoming_addr.sin_addr));
  }
  return;
}
void sss_handle_receive(SSSConn* conn)
{
    
    char Buf;
    memset(Buf,0,10);
    //OSTimeDlyHMSM(0,0,1,0);
    
    recv(conn->fd,Buf,2,0);
    printf("%s\nrecieved OK!\n\n",Buf);
    
    //OSTimeDlyHMSM(0,0,1,0);
      
    send(conn->fd,"2",2,0);
    printf("2 sent OK!\n\n");  
  
  return;
}
void SSSSimpleSocketServerTask()
{
  int fd_listen, max_socket; 
  struct sockaddr_in addr;
  static SSSConn conn;
  fd_set readfds; 
    
  if ((fd_listen = socket(AF_INET, SOCK_STREAM, 0)) < 0)
  {
    alt_NetworkErrorHandler(EXPANDED_DIAGNOSIS_CODE," Socket creation failed");
  }
  
  addr.sin_family = AF_INET; 
  addr.sin_port = htons(SSS_PORT); //SSS_PORT=30 &#65288;simple_socket_server.h&#65289;
  addr.sin_addr.s_addr = INADDR_ANY; 
  
  if ((bind(fd_listen,(struct sockaddr *)&addr,sizeof(addr))) < 0)
  {
    alt_NetworkErrorHandler(EXPANDED_DIAGNOSIS_CODE," Bind failed");
  }
    
  if ((listen(fd_listen,1)) < 0)
  {
    alt_NetworkErrorHandler(EXPANDED_DIAGNOSIS_CODE," Listen failed");
  }
  sss_reset_connection(&conn);
  printf(" Simple Socket Server listening on port %d\n", SSS_PORT);
   
  int cnt=0;
  sss_handle_accept(fd_listen, &conn);
  
  while(1)
  {
         sss_handle_receive(&conn);
        printf("cnt=%d\n\n",++cnt);
  } /* while(1) */
}

The laptop client is written under VC++ 6.0.

# include <Winsock2.h>
# include <stdio.h>
void main()
{
	WORD wVersionRequested;
	WSADATA wsaData;
	int err;
	fd_set rfd,wfd; 
	struct timeval timeout;
	
	wVersionRequested = MAKEWORD( 1, 1 );
	
	err = WSAStartup( wVersionRequested, &wsaData );
	if ( err != 0 ) {
		return;
	}
	
	if ( LOBYTE( wsaData.wVersion ) != 1 ||
        HIBYTE( wsaData.wVersion ) != 1 ) {
		WSACleanup( );
		return; 
	}
	char recvBuf;
	memset(recvBuf,0,100);
	char sendbuf;
	memset(recvBuf,0,100);
	
	SOCKET sockClient=socket(AF_INET,SOCK_STREAM,0);
	
	SOCKADDR_IN addrSrv;
	addrSrv.sin_addr.S_un.S_addr=inet_addr("169.254.228.120");
	addrSrv.sin_family=AF_INET;
	addrSrv.sin_port=htons(30);
	
	connect(sockClient,(SOCKADDR*)&addrSrv,sizeof(SOCKADDR));
	
	recv(sockClient,recvBuf,100,0);
	printf("%s\n\n",recvBuf);
	
	int cnt=0;
	while(1){		
		cnt++;
		send(sockClient,"1",2,0);
		printf("1 sent OK!\n\n");
		
		//Sleep(100);
		recv(sockClient,recvBuf,2,0);
		printf("%s\nrecieved OK!\ncnt=%d\n\n",recvBuf,cnt);
	}
	closesocket(sockClient);
	WSACleanup();
}

Probably FIFO buffers are filled up... Nios is VERY slow doing ethernet data transmissions, especially when You use InterNiche and RTOS. Don't expect anything more than 10-15Mbps.

Well... did You turn on optimization for Nios in compile parameters?

The best would be -Os, but still, should be fine... Anyway, I see that You're doing TCP connections, when I remembered, that I've tested UDP streams, when reached ~10Mbps. I'd say that it's just too slow to handle such speeds. What's the Nios CPU frequency and how many MIPS does it show?

No, because IP packet size is way much smaller, than 225k.The FIFO is inside TSE MAC. Why don't You use UDP? That's a common protocol for image/video streaming.