Cabletron Systems 9A128-01 Manual De Usuario

Accessing the ATM Connections Window

3-3

ATM Configuration

The Settings portion of the window contains a list box which displays information 
about each of the currently configured PVCs, as well as the fields used to 
configure new connections:

I/F

The device interface on which the PVC was configured. 

VPI

Displays the Virtual Path Identifier assigned to the 
connection; current versions of 9A128-01firmware allow 
values from 0 - 3. Virtual Path Identifiers are used to 
group virtual connections, allowing for channel trunking 
between ATM switches. Each VPI can be configured to 
carry many different channels (designated by VCIs) 
between two points.

VCI

Displays the Virtual Channel Identifier assigned to the 
connection; allowable values are 0 - 1023 for each VPI. 
Each assigned VCI must be unique within its defined 
VPI: for example, you can assign a VCI of 14 as many as 
four times: once with a VPI of 0, once with a VPI of 1, and 
so on. Remember, it is the combined VPI and VCI 
designations assigned to a channel that creates the 
grouping of virtual connections.

Encapsulation Type

Displays the method used to encapsulate LAN packets 
on the selected circuit. Current versions of 9A128-01 
firmware use 802.3 VC-based multiplexing for bridging 
protocols (designated VC MUX 802.3 Bridged); future 
versions will add support for ATM Forum LAN 
Emulation and Cabletron’s SecureFast Switching. You 
may also see some connections assigned a type of 
“other”; these are default connections that cannot be 
modified or deleted.

Status

Displays the current administrative status of the 
connection: enabled or disabled. In current versions of 
firmware, all connections are enabled by default, and 
cannot be disabled.

UpTime

The length of time the selected connection has been 
enabled.