Figure 6.5: Trunk Line Technologies Connect pairs of switches Trunk line Speed North American Digita/ Hierarch 56 kbps(Dso Signaling) 56 kbps(sometimes 64 kbps) T1(DS1 Signaling) 1.544 Mbps T3 (DS3 Signaling) 44.7 Mbps CEPT Multiplexing Hierarchy 64 kbps 64 kbps E1 2.048 Mbps E3 34.4 Mbps Note: CEPT, Conference of European Postal and Telecommunication 我国采用此标准 6-156-15 Figure 6.5: Trunk Line Technologies Trunk Line Speed North American Digital Hierarchy 56 kbps (DS0 Signaling) 56 kbps (sometimes 64 kbps) T1 (DS1 Signaling) 1.544 Mbps T3 (DS3 Signaling) 44.7 Mbps CEPT Multiplexing Hierarchy 64 kbps 64 kbps E1 2.048 Mbps E3 34.4 Mbps Connect Pairs of Switches Note: CEPT, Conference of European Postal and Telecommunication 我国采用此标准