Cisco BPX 8650, Installation And Configuration Manual

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Cisco BPX 8600 Series Installation and Configuration
Release 9.3.30, Part Number 78-12907-01 Rev. E0, May 2005
Chapter 19 Configuring Circuit Lines and Ports
Setting Up Ports and Virtual Ports
Virtual Ports
Virtual ports are logical interfaces such as virtual trunks, trunks, and ports. A maximum of 31 logical
entities are available on a BXM card.
Virtual ports is an optional feature that must be configured by Cisco on the BPX.
One or more virtual ports may function on a single port connected to CPE devices, directly or through
an ATM cloud. Although virtual ports, like ports, can connect directly to CPEs, they are generally used
to connect indirectly.
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
always ON, you can turn connection traffic shaping ON or OFF by using the
cnfportq command.
Each virtual port supports all Automatic Routing Management 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
cnfport command (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 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 total bandwidth.
Figure 19-3 Port Bandwidth
38569
Physical
interface
Virtual
port
CAC reserve
Virtual port
max bandwidth