SONET/SDH Specifies the framing used. Select either SONET
The MAX VPI Bits and MAX VCI Bits fields described below, are used to determine how many bits can be used within each cell header to define the value of the VPI and VCI. The value of the VPI and VCI fields identify the connection.
MAX VPI Bits can be used to identify which WAN connection to use. If you have several remote sites (London, Manchester and Leeds) you can specify a unique VPI value which identifies traffic going to that site. For example, the VPI value for London could be = 1, Manchester could be = 2, and Leeds could be = 3.
There are 11 bits available to be shared between the VPI and VCI. The default is 3 VPI bits and 8 VCI bits. You should not normally need to change the default settings. The adjacent ATM Switch can read the settings of these fields via ILMI and normally negotiates with the devices to use the lowest common denominator. If the ATM Switch is
MAX VPI Bits
Configuring an ATM Port |
Table
Desired Value of VPI | Number of bits |
| required |
|
|
0 | 0 |
0 or 1 | 1 |
within the range | 2 |
within the range | 3 (default) |
within the range | 4 |
|
|
Max VCI Bits The number of bits available for the VCI is calculated automatically, using the following equation:
MAX VCI Bits = (11 minus the value of Max VPI Bits)
ILMI VCC This number identifies the connection used for Interim Local Management Interface (ILMI) requests. The first field identifies the Virtual Path and the second field identifies the Virtual Channel.
You should only change the ILMI VCC if the ATM switch connected to ATM Module does not use the default ILMI VCC (VPI = 0, VCI = 16).
VCC connections with values 0 (zero) to 31 are reserved for standard connections and you should avoid using these values wherever possible.
Hardware Version Shows the version number of the ATM Module hardware.
