Using The Serial Module For E1- Or T1-Carrier Lines; Elements Of An E1- Or T1-Carrier Line - HP ProCurve Secure 7000dl Series Basic Management And Configuration Manual

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Using the Serial Module for E1- or
T1-Carrier Lines
When companies require dedicated, secure point-to-point wide area network
(WAN) connections, one of the available solutions is a leased E1- or T1-carrier
line. With an E1- or T1-carrier line, the connection is always active. Because
there is no dial-up process, data can be immediately transmitted at any time.
In Europe, Australia, South America, and Asia, Public Telephone and Tele-
graph (PTT) authorities offer E1-carrier lines, which provide 2.048 Mbps
bandwidth. In the United States, Canada, and in some areas of Japan, telcos
offer T1-carrier lines, which provide 1.544 Mbps bandwidth.
In Japan, PTTs offer T1-carrier lines and sometimes E1-carrier lines for data.
For traditional analog voice, these PTTs offer J1-carrier lines. (J1 lines are
outside the scope of this Basic Configuration and Management Guide.)

Elements of an E1- or T1-Carrier Line

All WAN connections, including E1- and T1 carrier lines, consist of three basic
elements:
the physical transmission media, such as the cabling, switches, routers,
and other infrastructure required to create and maintain the connection
electrical signaling specifications for generating, transmitting, and receiv-
ing signals through the various transmission media
Data Link Layer protocols, which provide logical flow control for moving
data between the peers (the devices at either end of a WAN connection)
Physical transmission media and electrical specifications are part of the
Physical Layer (or Layer 1) of the Open Systems Interconnection (OSI) model,
and Data Link Layer protocols are part of the Data Link Layer (or Layer 2).
(See Figure 5-1.)
Configuring Serial Interfaces for E1- and T1-Carrier Lines

Using the Serial Module for E1- or T1-Carrier Lines

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