Wan Technology (T1, E1 and DSL)

            T1 E1 T3 and E3 Circuit

             Lease Line: - Typically a point-to-point connection that interconnects two sites and provide dedicated bandwidth to the subscribers

 T1 Characteristics

Ø  Originally Designed for Telephone Networks

 Digital Circuits

Ø  T1s and E1s Popular in North America and Japan

Ø  E1s and E3s Popular in Outside of North America and Japan

Ø  Terminate on Channel Service Unit/Data Service Unit (CSU/DSU)

Ø  A Layer 2 Protocol (e.g. PPP) run over a circuit

	T1	E1	T3	E3
Bandwidth	1.544 Mbps	2.048 Mbps	44.7 Mbps	34.4 Mbps

                                                            

                                                                       DSL

Ø  Digital Subscriber line (DSL):- a Collection of broadband technology (e.g. ADSL SDSL and VDSL) that uses telephone line to Data Transmission

Ø  Asymmetric Digital Subscriber Line (ADSL) :- a type of DSL technology used in Home environments  

                               Asynchronous Transfer Mode (ATM):- Sends data in fixed-length cells (53 Byte of cells with 48 bytes of payload and 5 Byte of header), as supposed to variable length frames