First of all both sandwich and CDL comprises of 5 years program and they’re both for part-time students.
SANDWICH is also known as part-time. A sandwich degree, or sandwich course, is an academic degree or higher education course (also known as tertiary education) involving practical work experience in adition to academic study. Sandwich contains five session not semester and each session will take four month before completion. Starting from August till December every year for good five years, however the starting date for some institutions defers. All the courses in sandwich comprises of educational courses no professional course at all
CDL and CE also know as center for distance learning center and continue education involves all management courses, it encompasses management courses, social science courses and other related fields like political science, public admin e.t.c it program last for five years. Non of them offer professional course like engineering only ordinary course and each course is also done for five years.
Most of the courses are done online. CDL comprises of semester unlike sandwich and most likely lectures hold Friday and Saturday for the whole daily week basis ( atleast lecture hold two times a week)