2. Suppose that two Ethernet networks are interconnected through ATM network using interconnecting devices as shown in Figure Q4_1. The interconnecting device ID uses AAL5 in order to encapsulate Ethernet frames. The format of Ethernet frame is shown in Figure Q4_2 and the format of Adaptation Layer 5 packet (PDU, protocol data unit) is given in Figure Q4_3. Assume that a TCP application running on the host H1 sends two characters CR (carriage return) and LF (line feed) to a TCP application running on the host H2. Assume that the TCP header size is 20 bytes and the IP header size is 20 bytes. Calculate the number of ATM cells needed to transfer the TCP segment carrying these two characters between H1 and H2, and determine the padding length in the Ethernet frame and the padding length in the AALS PDU respectively. ATM network ID ID Ethernet Ethernet Figure Q4_1. 6 bytes 6bytes 2 bytes 46-1500bytes 4 bytes Dest_addr SRC_addr Type Body CRC Figure Q4_2.