Assume a sender sends 6 packets: packets 0, 1, 2, 3, 4, and 5. the sender receives an ACK with ackNo = 4. What is the interpretation if the system is using GBN?
it means that packet 3 has been received uncorrupted
it means that packets 0, 1, and 2 have been received uncorrupted
it means that packets 0, 1, 2 and 3 have been received uncorrupted
it means that packet 2 has been received uncorrupted