Establishing A Virtual Channel; Point-To-Point Calls - 3Com CoreBuilder 7000 Operation Manual

108 C 5: E
HAPTER STABLISHING
Establishing a Virtual
Channel
Transmitting Station

Point-to-Point Calls

ATM C
HANNELS
Displaying the Signaling Protocol Profile
To display or update the signaling protocol profile, see "Update Signaling
Protocol Profile" on page 202 in the Management Guide.
Figure 37 shows the steps involved in establishing a virtual channel. In
steps an external link (connection) is set up by signaling between the
1, 2
edge device and the switch. In step
and in steps , an external link is set up between the switch and the
4 5
edge device.
ATM Edge Device
1
2
VPI=0
VCI=32
To initiate a virtual
1
channel a SETUP
command
containing the
requirements for
the call, except for
The ATM Switch
3
VPI/VCI, is sent
selects the best output
by the edge
port according to the
device.
routing algorithm .
The ATM switch
2
The port and VPI/VCI
accepts or rejects
information is stored in
the proposed call
the switch matrix.
requirements
4 A SETUP command
The VPI/VCI
containing all
values are fixed by
requirements for the
the ATM switch
call is sent by the
and returned to the
output port of the
edge device.
switch.
Figure 37 Establishing a Virtual Channel
A point-to-point call is a collection of associated ATM VC or VP links that
connect two endpoints and enable data flow to and from both
endpoints.
an internal link is set up by routing,
3
ATM Switch
3
ATM Edge Device
4
VPI=1
VCI=44
The edge device
5
accepts or rejects
the proposed call
requirements.
If accepted, the
VPI/VCI values
are fixed for this
connection.
5
Destination Station