Sdh transmition analyzer des801 Main features 1. 155m ber analyzer for sdh discontinued / start operations. (g.826, m.2100) 2. 2m pdh ber analyzer¿g.826, m.2100¬ 3. C12 test: mapping/delete mapping 4. Sending alarm / respond test 5. Test au/tu pointer 6. Switching regular basis, alarm, frequency swing test 7. Protection switching test 8. Send and receive byte overhead analysis.