Jump to: navigation, search

OpenDaylight Virtual Tenant Network (VTN):VTN Coordinator:Virtual Network Construction

In the VTN, a virtual network is constructed using virtual nodes (vBridge, vRouter and vBypass), virtual interfaces, and virtual links. A network is configured with Layer 2 and Layer 3 functionalities by connecting the network through the virtual interfaces of virtual nodes.

VTN System Components diagram shows the virtual network elements in the VTN.

VTN System Components
Name of the Element Description
Virtual Node vBridge Logical representation of Layer 2 switch function implemented within the VTN.
vRouter Logical representation of Layer 3 switch function implemented within the VTN.

Only one vRouter can be defined in a VTN, and it can connect only to the vBridge.

vBypass Logical representation of connectivity between controlled networks.
vTerminal Logical representation of virtual node that is connected to the virtual network by means of an interface that is mapped to a physical port which is the source or target of a redirect section attribute in a flowfilter.
Virtual Interface interface The end point of the virtual node, which communicates with other virtual nodes.
Virtual Link vLink Logical representation of Layer 1 connectivity between virtual interfaces.


The Diagram below shows an example of a constructed virtual network. VRT is defined as the vRouter and BR1 and BR2 are defined as vBridges. The interfaces of the vRouter and vBridges are connected using vLinks.

Example of virtual network.png


Verifying the Status of Virtual Nodes

The operational status(oper status) of virtual nodes configured on the UNC is verified by executing the show topology or show status command in the respective mode. Virtual objects supporting operational status include:VTN, vBridges, vRouters, vTerminals, vBridge/ vRouter/vTerminal interfaces and vLinks. Specifically, vBypass and vBypass interfaces do not have an oper status attribute. The tables given below show how the oper status is updated for the corresponding resource

vBridge Interface
Oper Status of Interface Condition
UNKNOWN Controller disconnected.

Interface mapped to a port that is not known to the physical network.

UP Admin Status enabled.

Mapped to a logical port via port-map or boundary-map (using vLink) and the oper status of the corresponding logical port in the physical network is UP. Admin Status enabled. Linked to a vRouter interface via vLink command and Admin Status of the vLink is enabled.

DOWN Admin Status disabled.

Admin Status enabled. Mapped to a logical port via port-map, boundary-map and operation status of the corresponding logical port in the physical network is DOWN. Admin Status Enabled. Linked to a vRouter or vBridge interface via vLink command where Admin status of the corresponding vLink or vBridge interface is DOWN. Admin status is enabled and interface is not mapped to any logical-port or linked to any other interface.

vRouter Interface
Oper Status of Interface Condition
UNKNOWN Controller disconnected.
UP Admin Status enabled.

Linked to a vBridge interface via vLink command where Admin status of the corresponding vLink and the vBridge interface is enabled.

DOWN Admin Status enabled.

Linked to a vBridge interface via vLink command where Admin status of the corresponding vLink or vBridge interface is disabled. Admin status is enabled and interface is not linked to any other interface.

vTerminal Interface
Oper Status of Interface Condition
UNKNOWN Controller disconnected.

Interface is mapped to a port which is not known to the physical network.

UP Mapped to a logical port via port-map command and the oper status of the

corresponding logical port in the physical network is UP. Note: Admin status cannot be changed for vTerminal interface.

DOWN Mapped to a logical port via port-map command and the oper status of the

corresponding logical port in the physical network is DOWN. Interface is not mapped to a logical port.

vBridge
Oper Status of vBridge Condition
UNKNOWN Controller disconnected.

Oper status of an underlying vBridge interface is unknown.

UP vBridge with vlan-map configured and no configured underlying interfaces,

on which no path fault on PFC has occurred. vBridge on which no path fault on PFC has occurred with underlying interfaces and associated vLinks if any, that are all operationally up.

DOWN vBridge without any underlying interfaces / configured vlan-maps.

vBridge with any underlying interface/vLink with oper status DOWN. vBridge on which a path fault on PFC has occurred.

vRouter
Oper Status of vRouter Condition
UNKNOWN Controller disconnected.
UP vRouter with underlying interfaces and associated vLinks if any, that are all

operationally up.

DOWN vRouter without any underlying interfaces.

vRouter with any underlying interface or associated vLink with oper status DOWN.

vTerminal
Oper Status of vTerminal Condition
UNKNOWN Controller disconnected.

Oper status of the underlying vTerminal interface is UNKNOWN.

UP Oper status of the underlying vTerminal interface is UP.
DOWN Oper status of the underlying vTerminal interface is DOWN.

vTerminal without any underlying interfaces.

vLink
Oper Status of vLink Condition
UNKNOWN Controller disconnected.
UP vLink with admin status UP associated with interfaces that are operationally

up. vLink associated with vBypass interfaces which are boundary mapped.

DOWN vLink with admin status DOWN.

vLink associated with interface(s) that are operationally DOWN. vLink associated with vBypass interfaces which are not boundary mapped.

VTN
Oper Status of VTN Condition
UNKNOWN Controller disconnected.

Oper status of an underlying vBridge is unknown.

UP Has underlying virtual nodes and vLinks (if any), all of which are

operationally up.

DOWN Has one or more underlying virtual nodes / vLinks that are operationally

down. VTN that has no underlying virtual nodes. vLink associated with interface(s) that are operationally DOWN.

Mapping of Physical Network Resources

After constructing a VTN, it is necessary to map the physical resources to the constructed virtual network. This mapping identifies which virtual network each packet has to be transmitted or received based on the physical network resource, and which interfaces in the virtual network transmits or receives the packet

Mapping Methods
Mapping Command Description
Port mapping port-map This mapping method is used to map

physical port as an interface of virtual node (vBridge/vTerminal). port-map is enabled when the network topology is known in advance.

VLAN mapping vlan-map This mapping method is used to map

VLAN ID of VLAN tag in incoming Layer 2 frame with the vBridge. This mapping is used when the affiliated network and its VLAN tag are known. Whenever this mapping method is used, it is possible to reduce the number of commands to be set.

Boundary mapping boundary-map This mapping is used to map a

virtual link connecting two domains to a boundary created in realnetwork.

The interface if1 of vBridge (BR1) is mapped to the port GBE0/1 of switch1 using port-map. Packets received or transmitted by GBE0/1 of switch1 are considered as those from or to the interface if1 of vBridge. vBridge BR2 is mapped to VLAN 200 using vlan-map. Packets having the VLAN ID of 200 received or transmitted by the port of any switch in the network are mapped to the vBridge BR2.

Example of Mapping

Example of mapping.png