17.80. UUS1 - Implicit user-to-user signaling no. 1 
Feature:
DSS1 User-to-User Service
Function:
UUS1 - Implicit user-to-user signaling no. 1. Standardized ETSI feature in EURO-ISDN
for
exchanging limited signal messages from terminal to terminal (DSS1 ... digital subscriber
signaling system no. 1; EURO ISDN signaling). This enables a terminal to transfer
messages
which are not subject to network analysis transparently when a connection is set up.
Unlike
explicit user-to-user signaling number 1, the connection is always established in
implicit
user-to-user signaling number 1, even if the remote station does not support this
ETSI
feature.
The "user-to-user signaling no. 1 information", received via the network protocols
EDSS1NET
and EDSS1NETR is only forwarded to the destination system if the trunk parameter UUS1
is set
in the COT of the incoming seized trunk.
If the trunk parameter is not set in the COT of the incoming seized trunk, then the
data is
extracted from the SETUP message in the case of EDSS1NET and EDSS1NETR network protocols
and
is therefore not forwarded to the target device.
IMPORTANT:
In the case of all other protocols that transfer "user-to-user
signaling no. 1 information", the "user-to-user signaling no. 1 information" is always
forwarded to the target device, irrespective of the switch setting in the UUS1 trunk
parameter.
AMO Interrelationships:
COT Classes of Trunks:
US1E: UUS1 (user-to-user signaling no. 1) explicit
ETSC: UUS1 (user-to-user signaling no. 1) ETSI-compliant
Device types:
Digital CO trunk circuits, interface circuits and tie trunk circuits
For example, SOCOD, S2COD, SOCONN, S2CONN, etc.
Protocol variants:
Protocols for which the trunk parameter is to be set so that "user-to-user signaling
no. 1
information" can be forwarded when the connection is set up:
|
Protocol variants
|
Brief description
|
|
EDSS1NET
|
Protocol EDSS1 net side
|
|
EDSS1NETR
|
Protocol EDSS1 net side
|