Table Of Contents
Virtual Private Networks (VPNs)
Technology Description
VPN
Inventory and Information Model Objects (IMOs)
Virtual Routing Forwarding (VRF) Entity
Equivalent Routing Entry
Virtual Routing Entry
Multi Protocol BGP Entity
Equivalent Cross Virtual Routing Entry
Cross Virtual Routing Entry
Network Topology
Service Alarms
Virtual Private Networks (VPNs)
This chapter describes the level of support that Cisco ANA provides for VPNs, as follows:
•
Technology Description
•
Inventory and Information Model Objects (IMOs)
•
Network Topology
•
Service Alarms
Technology Description
VPN
BGP/MPLS VPNs, as defined in RFC 2547 and related drafts and standards, provide a Layer 3 VPN. With Layer 3 VPNs, each Provider Edge (PE) device acts like a set of virtual routers, one per VPN. The network provider configures the VPN membership of each PE router interface. In most cases, one port is used for multiple interfaces where each is associated with different VPNs. The port's view of the network is restricted to the VPNs of which it is a member, and it cannot address devices outside that environment. Conventional IP routing is the interface between Customer Edge (CE) and PE devices: Static routes can be provisioned on both the CE and PE, or for more complex scenarios, a routing protocol (such as RIP, OSPF or BGP) is run between CE and PE.
The network provider can also establish a suitable mesh of MPLS Label Switched Paths (LSPs) between all the PE routers that need to communicate. The PE devices qualify each external IP address that they learn with a per VPN identifier, and broadcast them to all other PE routers using an extended form of BGP depending on BGP connectivity. They also include an MPLS label that is specific to the destination route (or, in some implementations, the destination port). Through this process, the PE devices build up a complete map of the VPNs and destination labels. The PE routers then use this information to route the packets across the backbone network to the correct destination within the relevant VPN.
Inventory and Information Model Objects (IMOs)
This section describes the following IMOs:
•
Virtual Routing Forwarding (VRF) Entity (IVrf)
•
Equivalent Routing Entry (IRoutingEntries)
•
Virtual Routing Entry (IVrfEntry)
•
Multi Protocol BGP Entity (IMpBgp)
•
Equivalent Cross Virtual Routing Entry (ICrossVrf)
•
Cross Virtual Routing Entry (ICrossVrfRoutingEntry)
Virtual Routing Forwarding (VRF) Entity
The Virtual Routing Forwarding (VRF) Entity object describes the routing and address resolution protocols independent forwarding component of a MPLS-BGP based VPN router. It is bound by its Logical Sons attribute to all the Network layer IP Interface objects among which it is routing IP Packets.
Table 14-1 Virtual Routing Forwarding (VRF) Entity (IVrf)
Attribute Name
|
Attribute Description
|
Scheme
|
Polling Interval
|
Virtual Routing Table
|
Array of Equivalent Routing Entries
|
IP Core
|
Configuration
|
Exported Route Targets
|
Array of route target identifiers
|
IP Core
|
Configuration
|
Imported Route Targets
|
Array of route target identifiers
|
IP Core
|
Configuration
|
Route Distinguisher
|
Route distinguisher
|
IP Core
|
Configuration
|
ARP Entity
|
Address Resolution Entity (ARP Entity) (see Internet Protocol (IP))
|
IP Core
|
Configuration
|
Name
|
VRF name
|
IP Core
|
Configuration
|
Logical Sons
|
Array of all IP Interfaces among which this Virtual Routing Forwarding (VRF) Entity is routing IP packets
|
IP Core
|
N/A
|
Equivalent Routing Entry
The Equivalent Routing Entry and Virtual Routing Entry objects describe a routing table's entries. Each is an array of Virtual Routing Entries sharing a single IP Subnetwork destination.
Table 14-2 Equivalent Routing Entry (IRoutingEntries)
Attribute Name
|
Attribute Description
|
Scheme
|
Polling Interval
|
Routing Entries
|
Array of Virtual Routing Entries sharing a single destination
|
IP Core
|
Configuration
|
Virtual Routing Entry
Table 14-3 Virtual Routing Entry (IVrfEntry)
Attribute Name
|
Attribute Description
|
Scheme
|
Polling Interval
|
Next Hop BGP Address
|
Next hop BGP IP address
|
IP Core
|
Configuration
|
Incoming and Outgoing Inner Label
|
Incoming and outgoing inner MPLS label
|
IP Core
|
Configuration
|
Outer Label
|
Outer MPLS label
|
IP Core
|
Configuration
|
Destination IP Subnet
|
Final destination IP subnet
|
IP Core
|
Configuration
|
Next Hop IP Address
|
Next hop IP address
|
IP Core
|
Configuration
|
Type
|
Route entry type (Null, Other, Invalid, Direct, Indirect, Static)
|
IP Core
|
Configuration
|
Routing Protocol Type
|
Routing protocol type (Null, Other, "Local, Network Managed, ICMP, EGP, GGP, Hello, RIP, IS-IS, ES-IS, Cisco IGRP, BBN SPF IGP, OSPF, BGP, EIGRP)
|
IP Core
|
Configuration
|
Outgoing Interface Name
|
Outgoing IP interface name
|
IP Core
|
Configuration
|
Multi Protocol BGP Entity
The Multi Protocol BGP Entity object describes the BGP component of a MPLS-BGP based VPN router. It is bound by its Logical Sons attribute to all Virtual Routing Forwarding (VRF) Entity objects among which it is routing IP Packets.
Equivalent Cross Virtual Routing Entry
The Equivalent Cross Virtual Routing Entry and Cross Virtual Routing Entry objects describe the first dimension of a cross virtual routing table, as an array of Cross Virtual Routing Entry objects sharing a single Virtual Routing Forwarding (VRF) Entity destination.
Table 14-5 Equivalent Cross Virtual Routing Entry (ICrossVrf)
Attribute Name
|
Attribute Description
|
Scheme
|
Polling Interval
|
Virtual Routing Entries
|
Array of Cross Virtual Routing Entry objects sharing a single destination
|
IP Core
|
Configuration
|
Virtual Routing Entity Name
|
Virtual Routing Entity (VRF) name
|
IP Core
|
Configuration
|
Cross Virtual Routing Entry
Table 14-6 Cross Virtual Routing Entry (ICrossVrfRoutingEntry)
Attribute Name
|
Attribute Description
|
Scheme
|
Polling Interval
|
Outgoing Virtual Routing Entity Identifier
|
Outgoing virtual routing entity Object Identifier (OID)
|
IP Core
|
Configuration
|
Incoming and Outgoing Virtual Routing Tags
|
Incoming and outgoing virtual routing tags
|
IP Core
|
Configuration
|
Destination IP Subnet
|
Final destination IP subnet
|
IP Core
|
Configuration
|
Next Hop IP Address
|
Next hop IP address
|
IP Core
|
Configuration
|
Type
|
Route entry type (Null, Other, Invalid, Direct, Indirect, Static)
|
IP Core
|
Configuration
|
Routing Protocol Type
|
Routing protocol type (Null, Other, "Local, Network Managed, ICMP, EGP, GGP, Hello, RIP, IS-IS, ES-IS, Cisco IGRP, BBN SPF IGP, OSPF, BGP, EIGRP)
|
IP Core
|
Configuration
|
Outgoing Interface Name
|
Outgoing IP interface name
|
IP Core
|
Configuration
|
Network Topology
Cisco ANA discovers MPLS-BGP based Virtual Private (VPN) network topology by searching for the existence of the local Virtual Routing Forwarding (VRF) Entity's imported route targets in any remote side's VRF entity exported route targets.
Service Alarms
The following alarm is supported for this technology:
•
Duplicate IP on VPN Found/Duplicate IP on VPN Fixed. This alarm is disabled by default.
For detailed information about alarms and correlation, see the Cisco Active Network Abstraction 3.6.5 User Guide.