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Cisco MGX 8850 Routing Switch Command Reference
Release 2.0, Part Number 78-10467-04 Rev C0, October 2001
Chapter5 PNNI Commands dsppnni-intf
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PNNI includes a topology state routing protocol, which advertises detailed information about the peer
groups links and nodes. Links and nodes a re assi gne d metri c s an d att ributes that can be used to diagnose
or tune network behav io r.
The administrative weight (AW) is the cost to traffic that tr averses a port. The AW for a path is the sum,
in both directions, of t he individual AWs the egres s o f each port on the pa th .
The AW can be specified on the interface an d by th e s ervice class (or QoS class), and i t i s as so ci ate d
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 ther efo re how it di str ibutes 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-C BR Display the AW for constant bit rate (CBR) co nnections on this interfa ce. While
a cbr connection is active, th is o p tion limits its bit rate to a static value that
remains available u nt il th e conn ec t io n is t or n do w n. Th e b it rate is cha ra ct er ize d
by the peak cell rate (PCR) value.
Range: 0–4194304
AW-ABR Display the AW for available bit rate (ABR) connection s on this interface. While
an ABR connection is active, th at co nn ec tion changes its permitted bi t r at e
(bandwidth) in response to ATM layer t ra ns f er c ha ra cteristics. 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 24bit number AW for ABR on this interface.
Range: 0–4194304
AW-R TVB R Display the AW for real-tim e var iab le bit rate (rt-vbr) conne ct io ns on th i s
interface. rtvbr is intende d f o r re al- t im e ap pl ications requiring tigh tl y
constrained delay an d delay variation (voice/ vi deo applications). r tv b r is
characterized by peak cell rate (PCR), su stainable cell rate (SCR), and maxi mum
burst size (MBS).
Range: 0–4194304
AW-U BR Display the AW (QoS) used for unspecified bit rate (UBR) connections—this
includes switched virtual con n ect io n (S VC ) ping connections.
While a UBR connection is act ive, this option limits only the m aximum bit-rate
(bandwidth) of the connection—no bit rate is guaranteed.
Range: 0–4194304