记一次网络实训
这次网络实训是使用python去完成的
零比特填充
def bit():
num = input('请输入您要填充的标志字段')
list=0
list_result = []
# add=''
# index=0
for i in num:
# index+=1
if i == '1':
if list >=5:
list=0
list_result.append('0')
list_result.append('1')
list+=1
else:
list+=1
# add+=str(index)+' '+str(i)+' '
list_result.append('1')
else:
list=0
list_result.append(i)
# print("add",add)
result=''
for item in list_result:
result+=item
print(result)这个就是零比特填充
在HDLC的帧结构中，若在两个标志字段之间的比特串中，碰巧出现了和标志字段F（01111110）一样的比特组合，那么就会误认为是帧的边界。为了避免出现这种情况，HDLC采用零比特填充法使一帧中两个F字段之间不会出现6个连续1
海明码确认与创建
海明码确认
def sure_haiming():
# for index in range(get_hiaming_id(num)):
#print(type(index))
#result+=return_Gn(num,index)*2**(index-1)
num=input("请输入您要验证的海明码")
result=0
if get_hiaming_id(num)==5:
result=return_Gn(num,5)*2**4+return_Gn(num,4)*2**3+return_Gn(num,3)*2**2+return_Gn(num,2)*2+return_Gn(num,1)
elif get_hiaming_id(num)==4:
result =return_Gn(num, 4) * 2 ** 3 + return_Gn(num, 3) * 2 ** 2 + return_Gn(num,2) * 2 + return_Gn(num, 1)
elif get_hiaming_id(num) == 3:
result = return_Gn(num, 3) * 2 ** 2 + return_Gn(num, 2) * 2 + return_Gn(num, 1)
elif get_hiaming_id(num)==2:
result =return_Gn(num,2) * 2 + return_Gn(num, 1)
elif get_hiaming_id(num)==1:
result =return_Gn(num, 1)
elif get_hiaming_id(num)==6:
result=return_Gn(num,6)*2**5+return_Gn(num,5)*2**4+return_Gn(num,4)*2**3+return_Gn(num,3)*2**2+return_Gn(num,2)*2+return_Gn(num,1)
elif get_hiaming_id(num)==7:
result=return_Gn(num,7)*2**6+return_Gn(num,6)*2**5+return_Gn(num,5)*2**4+return_Gn(num,4)*2**3+return_Gn(num,3)*2**2+return_Gn(num,2)*2+return_Gn(num,1)
elif get_hiaming_id(num)==8:
result=return_Gn(num,8)*2**7+return_Gn(num,7)*2**6+return_Gn(num,6)*2**5+return_Gn(num,5)*2**4+return_Gn(num,4)*2**3+return_Gn(num,3)*2**2+return_Gn(num,2)*2+return_Gn(num,1)
print(result)
def get_hiaming_id(num):
len=num.__len__()+1
if len==1:
return 2
elif 2<=len<=4:
return 3
elif 5<=len<=11:
return 4
elif 12<=len<=26:
return 5
elif 27<=len<=57:
return 6
elif 58<=len<=120:
return 7
elif 121<=len<=247:
return 8
def return_Gn(list,n):
result=0
list_result=[]
start=int(2**(n-1))
end=int(2*2**(n-1))
tiao = int(2 ** (n - 1))
if start<=list.__len__():
if end > list.__len__():
end = list.__len__() + 1
while(start<=list.__len__()):
for i in range(start,end):
list_result.append(list[i-1])
start=end+tiao
end=start+tiao
if end>list.__len__():
end=list.__len__()+1
for item in list_result:
if item =='1':
result+=1
return result%2
else:
return 0海明码插入
def get_hiaming_id(num):
len=num.__len__()+1
if len==1:
return 2
elif 2<=len<=4:
return 3
elif 5<=len<=11:
return 4
elif 12<=len<=26:
return 5
elif 27<=len<=57:
return 6
elif 58<=len<=120:
return 7
elif 121<=len<=247:
return 8
def build_haiming():
str=input("请输入您要创建海明码的01串")
str_1=[]
id_1=get_hiaming_id(str)
id_charu=[]
for i in range(id_1):
id_charu.append(2**i)
# print('id_charu',id_charu)
j=0
for i in range(str.__len__()+id_charu.__len__()):
if i+1 not in id_charu:
str_1.append(str[j])
j+=1
else:
str_1.append(' ')
# print(str_1)
for i in range(1,id_1+1):
if 2**(i-1)<=str_1.__len__():
# print(i)
str_1[2**(i-1)-1]=build_p(str_1,i)
result_return=''
for item in str_1:
result_return+=item
print(result_return)
def build_p(list,n):
list_result = []
start = int(2 ** (n - 1))
end = int(2 * 2 ** (n - 1))
tiao = int(2 ** (n - 1))
if start <= list.__len__():
if end > list.__len__():
end = list.__len__() + 1
else:
end=end
while (start <= list.__len__()):
#print('start:',start-1,'end',end-1)
list_result.extend(list[start-1:end-1])
start = end + tiao
end = start + tiao
if end > list.__len__():
end = list.__len__() + 1
result=0
for item in list_result:
if item ==" ":
result+=0
else:
result+=int(item)
# print(result)
return str(result%2)crc8代码实现
def getyu(str1, str2):
index = 0
str1_new = ''
for item in str1:
if item == '0':
index += 1
else:
break
if index >= str2.__len__() - 1:
return True, str1[-8:]
else:
for i in range(index, index + 9):
if str1[i] == str2[i - index]:
str1_new += '0'
else:
str1_new += '1'
str1 = str1[:index] + str1_new + str1[index + 9:]
return False, str1
def crc8():
str_all = input("请输入您要传输的信息")
str_ = ''
str_list = []
for i in range(8):
str_ += '0'
for item in str_all:
item = str(bin(ord(item))[2:]) + str_
str_list.append(item)
in_ = 0
for item in str_list:
in_ += 1
str1 = (False, item)
str2 = '100000111'
while (True):
str1 = getyu(str1[1], str2)
if str1[0] == True:
break
str_send = item[:-8] + str1[1]
print('第{0}个元素的冗余码是{1},发送码是{2}'.format(in_, str1[1], str_send))
主代码展示
# 编写时间2021/6/16;14:07
# 编写 :刘钰琢
def bit():
def sure_haiming():
def return_Gn(list,n):
def get_hiaming_id(num):
def build_haiming():
def build_p(list,n):
def main():
bit()#零比特填充
sure_haiming()#验证海明码哪一步是错误的
build_haiming()#创建海明码
crc8()#crc8 实现
pass
if __name__=='__main__':
main()
