计算机网络试验1

1、杭州电子科技大学 实验报告 学生姓名：韩民杨 学 号： 指导教师：吴端坡 实验地点： 1#108实验时间： 2015-4-24一、实验室名称： 1#108二、实验项目名称： 计算机网络实验 1Coding on error dectecting algorithms(C+)三、实验学时：四、实验原理： C+编程五、实验目的： 利用 C+编程 CRC16校验及奇偶校验六、实验内容：Coding on error dectecting algorithms(C+)1. Cyclic redundancy checkUsing the polynomials below to encode rand

2、om generated data stream (40-100bits). Show the FEC, and encoded data frame.CRC-4x4+x+1ITUCRC-16x16+x15+x2+1IBM SDLCx32+x26+x23+.+x2+xZIP, RAR, IEEE 802 LAN/FDDI, IEEE 1394,CRC-32+1PPP-FCSFor the error patter listed below, what the conclusion does the receiver get Canthe receiver find the errorsCase

3、Error patternNo error0000 0000One error1000.000Two errors100.001Random errorsRandom error pattern2. Parity checkUsing even or odd parity check on random generated data stream (8-20bits). Show encoded data frame.For the error patter listed below, what the conclusion does the receiver get Can the rece

4、iver find the errorsCaseError patternNo error0000 0000One error1000.000Two errors100.001七、实验器材（设备、元器件） ：PC机一台，装有 C+集成开发环境。八、实验步骤：#include#include#include#include#include#include#define NO_ERROR 1#define ONE_ERROR 2#define TWO_ERROR 3#define RANDOM_ERROR 4#define RESULT 1#define CRC 0#define Parity 0

5、#define check 1int flag_parity;000Two errors100 .001Random errors Random error pattern*/ if(channel_way = NO_ERROR) char *result = NULL;int flagg=0;printf( 信道中传输数据： );for(int f =0;flength*8+len_d-1 ;f+) printf(%c,message_inputf);printf(n);printf( 正在检错中 n); printf( 检错结果： ); fflush(stdin);resultcrc_fu

6、nction(message_input,len,dividend,len_d,RESULT,crc-len_d);for(int i = 0;i len_d-1;i+)printf(%c,*result);if(*result) - 48 != 0) printf(n error! n); flagg =1; break; result+=1;if(flagg = 0) printf(n no error! n);if(channel_way = ONE_ERROR)char *result = NULL;message_input0 = (message_input0 - 48)(1-48

7、) + 48; printf( 信道中传输数据： );for(int f =0;flength*8+len_d-1 ;f+) printf(%c,message_inputf);printf(n);printf( 正在检错中 );printf( 检错结果： );result crc_function(message_input,len,dividend,len_d,RESULT,crc-len_d);for(int i = 0;i len_d-1;i+)if(*result = 1)printf(data error! n); break;elsecontinue;result+=1;if(c

8、hannel_way = TWO_ERROR)char *result = NULL;message_input0 = (message_input0 - 48)(1-48) + 48; message_inputlength*8-1 = (message_inputlength*8-1 - 48)(1-48) + 48;printf( 信道中传输数据： );for(int f =0;flength*8+len_d-1 ;f+) printf(%c,message_inputf);printf(n);printf( 正在检错中 );printf( 检错结果： );resultcrc_funct

9、ion(message_input,len,dividend,len_d,RESULT,crc); for(int i = 0;i len_d-1;i+)if(*result != 0) printf( data error! n);break;else continue; result+=1;if(channel_way = RANDOM_ERROR)char *result = NULL;int no;n);srand( (unsigned)time( NULL ) );.printf( 检错结果： );resultcrc_function(message_input,len,divide

10、nd,len_d,RESULT,crc); for(int i = 0;i len_d-1;i+)if(*result != 0)printf( data error! n);break; elsecontinue;result+=1;printf(*n);printf(n);printf(n);elseprintf(Please select the parity moden);printf(parity n);printf(parityn);scanf(%d,&flag_parity);char m = Parity_check(message_input,length*8,Parity)

11、; printf( 在信道中传输的 message:); message_inputlength*8 = m ;for(int message_number 0;message_number=length*8;message_number+) printf(%c,message_inputmessage_number);printf(n);*n);printf(printf(*analog channel*n);printf(*please choice the way of error*n);printf(*error*n);printf(*error*n);printf(*errors*n

12、);scanf(%d,&channel_way);if(channel_way = NO_ERROR)for(int f =0;flength*8;f+)printf(%c,message_inputf);printf( 正在检错中 n);charprintf（ 检错结果： ）;flag_parity_modeParity_check(message_input,length*8,check);if(flag_parity_mode = (message_inputlength*8)printf(no error!n);if(channel_way = ONE_ERROR)message_in

13、put0 = (message_input0 - 48)(1-48) + 48;for(int f =0;flength*8;f+)printf(%c,message_inputf);printf( 正在检错中 n);charprintf（ 检错结果： ）;flag_parity_modeParity_check(message_input,length*8,check);printf( error!n);if(channel_way = TWO_ERROR)message_input0 = (message_input0 - 48)(1-48) + 48; message_inputleng

14、th*8-1 = (message_inputlength*8-1 - 48)(1-48) + 48;for(int f =0;flength*8;f+)printf(%c,message_inputf);printf( 正在检错中 n);printf( 检错结果： );char flag_parity_mode = Parity_check(message_input,length*8,check);printf(no error!n);*n);printf(printf(n); printf(n); fflush(stdin);printf(do you want to continuey

15、/nn); scanf(%c,&flag);if(flag = y)continue;elsebreak;/*/function ： 完成字节转换成位的功能 /输入字符： In输出的二进制： Out void ByteToBit(char* out,const char* in,int bits) 中0=48for(j=0;jlen;j+)/* 把 1 传入48 表示为 0;*/ if(*input_p=48)入界面2. 输入数据3. CRC校验1)No error2) One error3) Two errors4) Random errors4. 奇偶校验 界面 Even parity1) No error2) One error3)