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Feature Reference
Trunks and trunk groups
Administrator’s Guide for Avaya Communication Manager
1743
November 2003
Transmission and supervisory signaling
A trunk is named for its transmission characteristics. For example, trunks are always classified by the
direction of the traffic they allow:
•
One-way incoming trunk
—
A local trunk that can be selected (seized) by the far-end connected
media server or switch.
•
One-way outgoing trunk
—
A trunk that can be seized by the local switch to call the far-end
server or switch.
•
Two-way trunk
—
A trunk that can be seized by either of the connected servers/switches.
Another transmission characteristic is signaling, which is the transmission of supervision, address,
alerting, or other switching information. Supervisory signaling establishes or sets up the connection of
the local media server or switch to the distant server or switch. In general, supervisory signaling has 2
phases:
•
Seizure signal
—
The originating office’s signal for a request for service from the distant office.
•
Start-dial signal
—
The distant office’s acknowledgment that it is ready to accept dialing from the
originating office.
Seizure signals
Ear & Mouth (E&M) supervision
E&M supervision is a symmetric signaling scheme used on private network trunks. DC voltage levels are
sent over E&M leads, which are separate from the transmission path. E & M signals indicate on-hook and
off-hook states for each end of the connection path.
ISDN
Incoming
Outgoing
Two-way
Digital
Any kind of voice or
voice grade data.
Yes
PCOL
Incoming
Outgoing
Two-way
Analog
only
Only voice and
voice-grade data.
No
SIP
Incoming
Outgoing
Two-way
Digital
Voice only
Yes
Tie, Access
Incoming
Outgoing
Two-way
Either
Any kind of voice or
data traffic.
Yes
Type of trunk
Direction
Analog or
Digital?
Traffic supported
Transmits
digits?
Содержание Communication Manager
Страница 320: ...Setting Up Telecommuting Training Users 320 Administrator s Guide for Avaya Communication Manager November 2003...
Страница 416: ...Managing Group Communications Observing Calls 416 Administrator s Guide for Avaya Communication Manager November 2003...
Страница 502: ...Administering Media Servers SNMP Agents 502 Administrator s Guide for Avaya Communication Manager November 2003...
Страница 602: ...Phone Reference Internet Protocol IP Softphones 602 Administrator s Guide for Avaya Communication Manager November 2003...
Страница 1338: ...Screen Reference Vector Directory Number 1338 Administrator s Guide for Avaya Communication Manager November 2003...
Страница 1832: ...Glossary and Abbreviations Z 1832 Administrator s Guide for Avaya Communication Manager November 2003...
Страница 1854: ...Index X 1854 Administrator s Guide for Avaya Communication Manager November 2003...