IP/MPLS network elements

This section includes a summary table with the key elements in the ENP model related to IP/MPLS networks. Links to the Javadoc are included, of interest to those developing ENP applications or ad-hoc modules.

Class	Name	Description
AbstractIpIgpInstance	Abstract IGP instance	This element represents an abstract IGP instance, providing common behavior for specific IGP types that extend it (e.g., OSPF IGP instances).
BidiIpInterface	IP interface	An IP interface is a logical element located within an IP logical port or an aggregation of IP logical ports (LAG). IP interfaces are characterized by an IP/mask address, and may also include a VLAN ID when connected to an Ethernet link. IP links originate and terminate in IP interfaces: a link exists between two interfaces if they are connected by a transport connection (Ethernet, optical, virtual transport, etc.), and if they share an IP address with the same IP prefix.
IpAutonomousSystem	IP Autonomous System	This element represents an IP Autonomous System.
IpDesignRule	IP Design Constraint	This element represents a user-defined constraint to be applied to the IP topology of the network. It allows users to limit the number of IP nodes with specific tags that can be IP neighbors of nodes with other specific tags. This flexible scheme offers users the ability to enforce practical IP topology rules based on operational considerations in their IP designs. For instance, it can enforce a policy where nodes of a certain user-defined type (e.g., edge nodes) must connect to at least two nodes of other user-defined types (e.g., core nodes) to meet internal policy requirements.
IpLogicalPortBidi	IP logical port	This element represents an IP logical port located within a node. IP ports can be configured with one or more IP interfaces. IP logical ports are bidirectional elements capable of transmitting and receiving traffic through their incoming and outgoing IP links (the ones incoming/outgoing from their IP interfaces). IP traffic to/from the link is transported via the associated transport connection. IP logical ports within the same node, connected via transport connections to the same other node, can be organized into Link Aggregation Groups (LAGs). By creating a LAG, all aggregated ports appear to the upper IP layer as a single logical port with aggregated capacity. IP traffic transmitted through a LAG is distributed among its active (non-failed) underlying ports in proportion to their port rates; i.e., if all ports in the LAG have the same rate, the traffic is evenly distributed.
IpMulticastFlow	IP multicast flow	This element represents an IP multicast flow. Information on simulating IP multicast in ENP is available in the documentation section on IP multicast simulation.
IpTransportRule	IP Transport Rule	This element represents a user-defined constraint to determine the preferred transport technology for connecting two IP nodes. This information guides the multilayer network design algorithm. A node pair (n1,n2) matches a rule if either node n1 matches the first list of tag regular expressions and n2 matches the second, or vice versa. If no transport rule matches the IP node pair, Ethernet is assumed as the preference, followed by Optical link (ODU), and then Virtual transport.
NodeExternal	IP external node / network	This element represents an external IP node in ENP designs, used to represent IP networks connected to the network of interest. An external node can be connected to any number of internal nodes via bidirectional injection links, which have infinite capacity. External nodes can serve as the start/end points of IP demands.
OspfArea	OSPF area	This element represents an OSPF area defined within a specific OSPF instance in an IP Autonomous System. By default, OSPF instances have a single area known as the backbone area. Area distribution affects traffic routing; refer to the ENP IGP simulation documentation for more information.
OspfIgpInstance	OSPF IGP instance	This element represents an OSPF instance defined within the IP Autonomous System. When an Autonomous System has multiple IGP instances defined, it's possible to configure, for each IP demand, multicast flow, and tunnel, which IGP instance will be applied to determine its routing within the AS.
UnidiIpDemand	Unicast IP demand	This element represents unicast IP traffic demand between two specific IP nodes, whether internal or external. IP demands are primarily characterized by their end nodes, offered IP traffic (which may or may not be satisfied), acceptable end-to-end latency, and QoS class. IP demands may be private or public. Private demands are routed exclusively via specific MPLS-TE tunnels, while non-private demands follow regular IP forwarding.
UnidiIpLink	Unidirectional IP link	This element represents an IP link between two IP interfaces. IP links are created by the ENP simulator when two IP interfaces are in ports connected via a functional transport connection (point-to-point or Ethernet point-to-multipoint).
UnidiIpLinkInjection	Unidirectional external injection link	This element represents a unidirectional segment of an IP injection link between an IP external node and an IP internal node. At most, one injection link can exist between the same two nodes. Injection links have infinite capacity and are always paired bidirectionally (two injection links in opposite directions).
UnidiMplsTeTunnel	Unidirectional MPLS-TE tunnel	This element represents a unidirectional MPLS-TE (Traffic Engineering) tunnel defined in the network. Refer to the MPLS-TE simulation section in the documentation for more information.
Vpn	IP Virtual Private Network (VPN)	This element represents an IP Virtual Private Network (VPN) defined within the network. Refer to the ENP VPN simulation documentation for more information.
VpnNode	Virtual Private Network (VPN) Node	This element represents the configured membership of a specific IP node (internal or external) in a VPN. Refer to the ENP VPN simulation documentation for more information.