Cisco BPX 8600 Series, Руководство по установке и настройке

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Cisco BPX 8600 Series Installation and Configuration
Release 9.3.0, Part Number 78-10674-01 Rev. D0, July 2001
Chapter 21 Configuring ATM Connections
ATM Connection Flow
ATM Connection Flow
ATM Connection Flow through the BPX
The BPX supports the standard ATM service types, CBR, rt-VBR, nrt-VBR, ABR, and UBR. When
adding a connection by using the addcon command, you select these service types by entering one of
the CLI service type entries shown in Table 21-2 when prompted:
The BPX also supports ATM to Frame Relay Network Interworking and Service Interworking
connections. When adding a connection by using the addcon command, you select these service types
by entering one of the CLI service type entries shown in Table 21-3 when prompted:
Advanced CoS Management
Advanced CoS management provides per-VC queueing and per-VC scheduling. CoS management
provides fairness between connections and firewalls between connections. Firewalls prevent a single
non-compliant connection from affecting the QoS of compliant connections. The non-compliant
connection simply overflows its own buffer.
The cells received by a port are not automatically transmitted by that port out to the network trunks at
the port access rate. Each VC is assigned its own ingress queue that buffers the connection at the entry
to the network. With ABR with VSVD or with Optimized Bandwidth Management (ForeSight), the
service rate can be adjusted up and down depending on network congestion.
Table 21-2 Standard ATM Type and addcon
CLI Service Type Entries Connection Description
CBR cell bit rate
rt-VBR real time VBR
nrt-VBR non real time VBR
UBR unspecified bit rate
ABRSTD ABR per forum standard, with option to enable VSVD congestion control.
ABRFST ABR with Cisco ForeSight congestion control.
Table 21-3 ATM to Frame Relay Network and Service Interworking
CLI Service Type Entries
for addcon command
Connection Description
ATFR ATM to Frame Relay Network Interworking
ATFST Same as ATFR with ForeSight
ATFT ATM to Frame Relay Transparent Service Interworking
ATFTFST Same as ATFT with ForeSight
ATFX ATM to Frame Relay Translational Service Interworking
ATFXFST Same as ATFX with ForeSight