T1 PRI For PBX Telephony
A T1 PRI, also called an ISDN PRI, is a "Primary Rate Interface"
providing 23 individual digitized telephone lines plus data such
as Caller ID on a single digital telephone trunk line. A PRI line
is usually much less expensive than a dozen or more analog business
Channelized and Unchannelized
A T1 line may be configured as a single large pipe offering 1.5
Mbps data transport or as 24 individual channels of 64 Kbps each,
ideal for use as individual outside telephone lines to support
Key or PBX business telephone systems.
Channelized T1 vs ISDN PRI
T1 lines can support two protocols of switched circuit telephony.
Channelized T1 lines offer 24 phone lines using in-band signaling.
ISDN PRI, or Primary Rate Interface, offers 23 phone lines and
common channel signaling that can include data such as ANI Automatic
Number Identification or Caller ID.
Virtual Private Networks Link
Many businesses now have more than one office location or need
to include other facilities such as warehouses and remote data
centers. A VPN or Virtual Private Network allows you to use dedicated
Internet connections as private network connections through data
encryption. A VPN solution is generally much less expensive than
extensive dedicated point to point circuits.
T1 Line Bandwidth Explained
A T1 line is typically referred to as having a bandwidth of 1.5
Mbps. The precise line speed is 1.544 Mbps. However, the usable
bandwidth or payload is actually 1.536 Mbps. The difference is
8 Kbps which is used for line framing to keep the transmitting
and receiving ends of the circuit in synchronization.