Question

3.

The fields in a PPP header are as follows (source: Point to Point Protocol Structure) (Alternate source: TCPI Guide.com)

Using the correct data types (this is essential to the assignment), design a data structure in C++ language that would represent this frame. Please use 10 bytes for the information and 5 bytes for the padding.

Name	Number of bytes	Description
Flag	1	0x7E, the beginning of a PPP frame
Address	1	0xFF, standard broadcast address
Control	1	0x03, unnumbered data
Protocol	2	PPP ID of embedded data
Information	variable (0 or more)	datagram
Padding	variable (0 or more)	optional padding
Frame Check Sequence	2	frame checksum
Flag	1	0x7E, omitted for successive PPP packets

Answer 1

#include <iostream.h>
using namespace std;

void main(){
  
   struct ppp{
       char name[5];       //for 5bytes
       char nbytes[5];  
       char info[10];        //for 10 bytes
   }
   typedef struct ppp ppp;

   void main(){
       srtruct ppp arr[8];
       arr[0].name = 'Flag';
       arr[0].nbytes = '1';
       arr[0].info= '0x7E, the beginning of a PPP frame';

   }
}

like this fill information in arr[] which is a custom made data type fotthis PPP header packet.