Nodes and sites
A node or site is a network modeling construct that
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represents devices (nodes) and hierarchical groupings (sites), and
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provides visual cues and organizational structure for network planning and analysis.
Node: A node is a device in the network, which can be one of three types: physical, pseudonode (PSN), or virtual. The Type property distinguishes whether the node represents a real device or an abstraction, such as a single node representing a number of edge nodes connected in the same way to the network. A physical node is a Layer 3 device, or router. Physical and virtual nodes behave in the same way within Cisco Crosswork Planning. A pseudonode is typically represents a Layer 2 device or a LAN.
Nodes can reside both inside and outside of sites. The external arrangement could be useful for small networks where routers are not geographically dispersed.
Site: A site is collection of nodes and/or other sites, potentially forming a hierarchy of sites. Any site that contains other sites is called the parent site.
Both nodes and sites have simulated traffic, while nodes also have measured traffic.
Network plot visualization
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Nodes appear as blue router icons (
) in the network plot. The border color indicates the traffic sourced from and destined to the node. A light blue outline
indicates that the node is selected. For more information, click the
icon in the network plot.
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Sites appear as blue circles (
) in the network plot. The border color indicates the traffic utilization of all the nodes and circuits inside the site, including
all nested nodes and circuits. A light blue outline indicates that the site is selected. The number inside the circle indicates
the number of nodes in the site. For more information, click the
icon in the network plot.
Note that sites can contain L3 nodes. Empty sites and sites containing L3 nodes appear in the L3 view.
Parent sites and contained objects
A parent site is a site that
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contains other sites, nodes, or circuits (known as contained objects)
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defines hierarchical relationships between sites through nesting, and
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enables filtered views and management of all objects within its hierarchy.
Contained or nested objects are nodes, sites, or circuits that reside within a parent site. These are also referred to as children and are often geographically co-located. For example, a site representing a Point of Presence (PoP) can be a parent site if it contains routers.
The site’s Parent site property defines whether it is nested within another site. If it is empty, the site is not nested.
Network plot visualization
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In the network plot, the parent site shows all egress inter-site interfaces of all nodes contained within it, no matter how deeply the nodes are nested. This visualization logic applies to each child site plot contained within the parent.
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Selecting a site from the network plot does not select the sites or nodes under it.
Filtering to contained objects
To filter to the sites or nodes contained within a site, select the site and click
> Filter to contained.
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Direct: filters to only those objects contained immediately within it.
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All: filters to all objects contained within it, no matter how deeply they are nested.
Delete sites
Selecting a site from the network plot does not select the sites or nodes under it except when deleting the site. In this case, all objects within a site are selected for deletion. However, in the confirmation that appears, you have the option to keep the contained sites and nodes. If you do, then the objects that are contained directly within it are moved to be on the same level as the site that is removed. The other, more deeply nested objects maintain their parent relationships.
PSN nodes
A PSN is a node that
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represents pseudonodes, which are used to model LANs or switches that connect more than two routers
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is used for IGP modeling and BGP peer modeling, and
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has a Type property of PSN.
In IGP networks, a LAN interconnecting multiple routers is represented by a PSN node, with circuits connected to each of the nodes representing the interconnected routers. Both OSPF and IS-IS have a built-in system. In this system, one of the routers on the LAN is the designated router (DR) for OSPF or the designated intermediate system (DIS) for IS-IS. The PSN node uses the name of this designated router. Cisco Crosswork Planning creates nodes with a property Type of PSN automatically during IGP discovery.
When BGP peers are discovered, Cisco Crosswork Planning might find that a router is connected to multiple peers using a single interface. This is typical at switched Internet Exchange Points (IXPs). Cisco Crosswork Planning then creates a node with a property Type of PSN, and connects all the peers to it, each on a different interface.
Points to consider when working with PSN nodes
Consider these points when working with nodes that have PSN as a Type property:
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Two PSNs cannot be connected by a circuit.
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If a PSN node is created by Cisco Crosswork Planning, “psn” is added as a prefix to the designated router’s node name.
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When creating demand meshes, Cisco Crosswork Planning does not create demands with nodes of Type PSN as sources or destinations. Creating demands with nodes of Type PSN as sources or destinations is possible in manual demand creation, but this is not recommended. Cisco Crosswork Planning sets the IGP metric for all egress interfaces from a node of Type PSN to zero. This ensures that the presence of a PSN in a route does not add to the IGP length of the path.
Node configuration fields
These fields are commonly used when configuring a node.
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Name: Specifies the name for the node.
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IP address: This value is often the loopback address used for the router ID.
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Site: Specifies the name of the site in which the node exists. If left empty, the node resides in the network plot. This method provides a convenient way to create a site when creating the node, move nodes from one site to another, or remove nodes from a site so it stands alone in the network plot.
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AS: Specifies the name of the AS in which this node resides, identifying its routing policy. This field can be left empty if no BGP is being simulated.
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BGP ID: Specifies the IP address that is used for BGP.
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Function: Indicates whether this is a Core or Edge node.
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Type: The node type, which is physical, PSN, or virtual. Because a PSN node represents a Layer 2 device or a LAN, interfaces on a PSN must all have their IGP metrics set to zero, and two PSN nodes cannot be directly connected to one another. If you change a node type to PSN, Cisco Crosswork Planning automatically changes the IGP metrics on its associated interfaces to zero.
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Longitude and Latitude: Indicates the geographic location of the node within the network plot. These values are relevant when using geographic backgrounds.
To create nodes, refer to Create objects, where Object is Node.
Site configuration fields
These fields are commonly used when configuring a site.
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Name: Specifies the unique name for the site.
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Display name: Specifies the site name that appears in the plot. If this field is empty, the Name entry is used.
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Parent site: Indicates the site that immediately contains this site. If empty, the site is not contained within another one.
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Location: Select the location from the list of cities. To automatically place a site in its correct geographic location and update the Longitude and Latitude fields, enter the airport code and press Enter.
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Longitude and Latitude: Specifies the geographic location of the site within the network plot. These values are relevant when using geographic backgrounds.
To create sites, refer to Create objects, where Object is Site.
Merge nodes
This topic describes how to merge multiple network nodes into a single virtual node to simplify network planning and accelerate calculations.
Real network topologies often include several nodes—typically edge nodes—that are connected to the network in the same way. For example, all nodes might connect to the same core node or to a pair of core nodes. For planning and design of the network core, it is often desirable to merge these physical nodes into a single virtual node, which simplifies the plan and accelerates the calculations and simulations performed.
![]() Note |
Merging nodes changes the actual plan, not just the visual representation. |
The name of a newly merged node can be based on the site name, selected node name (base node), or have a new user-specified name. The effects of merging nodes are:
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Reattach circuits from other nodes to the base node.
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Move demands to or from other nodes to the base node.
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Move LSPs to or from other nodes to the base node.
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Set base node traffic measurements to the sum of measurements of the selected nodes.
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Delete other nodes.
Complete these steps to merge nodes.
Procedure
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Step 1 |
Open the plan file (see Open plan files). It opens in the Network Design page. |
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Step 2 |
From the toolbar, choose Actions > Initializers > Merge nodes. |
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Step 3 |
Select the nodes that you want to merge in the Merge Nodes page. If you do not select any nodes, Cisco Crosswork Planning merges all nodes. |
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Step 4 |
Click Next. |
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Step 5 |
Select whether to merge the nodes per site or merge them into one node.
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Step 6 |
Click Next. |
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Step 7 |
Review the effects of node merge. If they are acceptable, then click Merge. |

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