Filter
Top Products
19-4
Cisco BPX 8600 Series Installation and Configuration
Release 9.3.10, Part Number 78-11603-01 Rev. D0, July 2001
Chapter 19 Configuring Circuit Lines and Ports
Setting Up Ports and Virtual Ports
Traffic shaping has previously been supported on ports and on connections. Virtual ports on BPX
switches provide hierarchical traffic shaping, which means both virtual port traffic shaping and
connection traffic shaping.
A virtual port may carry multiple PVCs or PVPs. VI traffic shaping capability is provided per virtual
port. Additionally, connection traffic shaping is available on a QOS basis. While virtual port shaping is
alwaysON,youcanturnconnectiontrafficshapingONorOFFbyusingthecnfportq command.
Each virtual port supports all Automatic Routing Management (AutoRoute) traffic types that are
currently supported by ports.
To set the maximum bandwidth available for use on that virtual port, use the Bandwidth parameter of
the command cnfport (see Figure 19-3). This parameter is similar to the Bandwidth parameter used for
ports. However, while the Bandwidth parameter is configurable on a virtual port, on a port, this
parameter is not configurable; it is automatically set to the line speed.
You can configure a virtual port’s bandwidth to the full port bandwidth or a subset thereof. However,
the bandwidth sum of all virtual ports on a port cannot exceed the port’s total bandwidth.
Figure 19-3 Port Bandwidth
Virtual Port Examples
This section describes two of many possible examples of virtual port configurations.
• Type I Virtual Ports can have PVP or PVC connections terminating on it.
All traffic through this Virtual Port is constrained to the Virtual Port’s configured bandwidth
(Virtual Port shaping). Moreover, if connection shaping is enabled (per QOS), each connection will
be constrained to its PCR and be given a fair chance to transmit by using WFQ (Weighted Fair
Queuing).
• Type II Virtual Ports have PVC connections all with the same VPI terminating on it.
As with the type I Virtual Port above, all traffic through this port is constrained to the Virtual Port’s
configured bandwidth. If connection shaping is enabled, each connection will be constrained to its
PCR and undergo WFQ.
The BPX switch software does not distinguish between the two types of virtual ports.
Depending on the interface type, UNI or NNI, the maximum number of PVPs will be 255 or 4095
respectively. The maximum number of VCIs is 65535.
38569
Physical
interface
Virtual
port
CAC reserve
Virtual port
max bandwidth