3com 7600 Benutzerhandbuch
12-4
C
HAPTER
12: ATM, LAN E
MULATION
,
AND
V
IRTUAL
LAN
S
Q
Point-to-point and point-to-multipoint connections
Switched Virtual
Channels
SVC connections are defined dynamically as they are needed and released
when not needed, using signalling as per ATM Forum UNI standards. By
using SVC, ATM devices can exchange connection characteristics when
establishing connections. These connections remain active for as long as
the application demands. Both point-to-point and point-to-multipoint
connections can be established. SVC eliminates the need for an external
management station for setting up virtual channels.
when not needed, using signalling as per ATM Forum UNI standards. By
using SVC, ATM devices can exchange connection characteristics when
establishing connections. These connections remain active for as long as
the application demands. Both point-to-point and point-to-multipoint
connections can be established. SVC eliminates the need for an external
management station for setting up virtual channels.
The characteristics of the SVC connection include:
Q
Connections initiated by the user/application
Q
Connections established and released dynamically
Q
Connections established via the signalling protocol
Q
Varied connection duration
Interim Local
Management
Interface (ILMI)
Management
Interface (ILMI)
The Interim Local Management Interface (ILMI) communication protocol
is an open management protocol that supports the bi-directional
exchange of management information between all end-stations and the
switches to which they are connected.
is an open management protocol that supports the bi-directional
exchange of management information between all end-stations and the
switches to which they are connected.
The ILMI functions for a UNI provide status, configuration, statistics, and
control information about link and physical layer parameters at the UNI.
In addition, it provides for address registration across the UNI. ILMI
communications use SNMP directly over the AAL5.
control information about link and physical layer parameters at the UNI.
In addition, it provides for address registration across the UNI. ILMI
communications use SNMP directly over the AAL5.
For any ATM device, there is a connecting device associated with each
UNI that supports the ILMI functions for that UNI.
UNI that supports the ILMI functions for that UNI.
ILMI Management
Information Base
(MIB)
Managed objects are accessed via a virtual information store, termed the
Management Information Base or MIB. Each object defined in the MIB
has a name, a syntax, and an encoding. The UNI ILMI attributes are
organized in a standard MIB structure; there is one UNI ILMI MIB structure
instance for each side of the UNI.
Management Information Base or MIB. Each object defined in the MIB
has a name, a syntax, and an encoding. The UNI ILMI attributes are
organized in a standard MIB structure; there is one UNI ILMI MIB structure
instance for each side of the UNI.
The IILMI MIB provides the management application with the capability to
control and monitor the ATM link and physical layer. The following types
of management information are available in the ILMI ATM UNI MIB:
control and monitor the ATM link and physical layer. The following types
of management information are available in the ILMI ATM UNI MIB:
abtthgde.book Page 4 Tuesday, June 23, 1998 10:29 AM