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Cisco MGX 8850 Routing Switch Command Reference
Release 2.0, Part Number 78-10467-04 Rev C0, October 2001
Chapter 5
PNNI Commands
dsppnni-intf
Display Contents
PNNI includes a topology state routing protocol, which advertises detailed information about the peer
groups links and nodes. Links and nodes are assigned metrics and attributes that can be used to diagnose
or tune network behavior.
The administrative weight (AW) is the cost to traffic that traverses a port. The AW for a path is the sum,
in both directions, of the individual AWs the egress of each port on the path.
The AW can be specified on the interface and by the service class (or QoS class), and it is associated
with each port. AW is a defining factor when routes are selected. The AW parameters influence how
PNNI selects paths in the peer group and therefore how it distributes each SVC and SPVC. PNNI route
selection can also key on AW to exclude certain links from routing. The application of such exclusion
can be to defining a backup link for use only when no bandwidth is available on the primary link.
Related Commands
cnfpnni-intf
AW-CBR
Display the AW for constant bit rate (CBR) connections on this interface. While
a cbr connection is active, this option limits its bit rate to a static value that
remains available until the connection is torn down. The bit rate is characterized
by the peak cell rate (PCR) value.
Range: 0–4194304
AW-ABR
Display the AW for available bit rate (ABR) connections on this interface. While
an ABR connection is active, that connection changes its permitted bit rate
(bandwidth) in response to ATM layer transfer characteristics. PNNI
periodically polls for the unused bandwidth at the ATM level, then adjusts the
ABR connection bit rate in direct relation to the available bandwidth.
Displays the 24 bit number AW for ABR on this interface.
Range: 0–4194304
AW-RTVBR
Display the AW for real-time variable bit rate (rt-vbr) connections on this
interface. rtvbr is intended for real-time applications requiring tightly
constrained delay and delay variation (voice/video applications). rtvbr is
characterized by peak cell rate (PCR), sustainable cell rate (SCR), and maximum
burst size (MBS).
Range: 0–4194304
AW-UBR
Display the AW (QoS) used for unspecified bit rate (UBR) connections—this
includes switched virtual connection (SVC) ping connections.
While a UBR connection is active, this option limits only the maximum bit-rate
(bandwidth) of the connection—no bit rate is guaranteed.
Range: 0–4194304