Importance of Network Visualization
Network visualization is essential in having that complete overview of not only physical network components but logical and virtualized. This expands the scope of inventory and allows for the end to end network view to become more accessible to multiple organizations who rely on accurate network information to make important decisions affecting both CAPEX (additional hardware needed for capacity enhancements or removing under utilized equipment from data centers) and OPEX (capability of identifying bottlenecks and performance issues). Network topology visualization is essential for not only network operators but network planners who use network topology to gain a greater understanding of how the network is deployed along with how all the physical, logical and virtual components are interconnected. Additional aspects detailing the importance of network inventory topology include:
- Capacity Planning: Enables ease of forecasting hardware requirements and better plan for network expansions and optimizations. Provides a network visualization from Cell Site, Edge, LDC, RDC and NDC.
- Troubleshooting: Having the ability to visualize the network and highlight failing points at a glance reduces MTTR. This helps to minimize outages and reduces the overall time to investigate and resolve issues.
- Detailed Topology Network Map: Importance of having a Visualization of the physical, logical, and virtual network components for network improvements
- Resources Distribution: Next Generation of networks requires the ability to scale based on required SLAs or network and customer demands. Having a proper visualization simplifies the complexities of managing changing workload distribution.
ServiceNow Inventory Topology UI Implementation Details
Visualizing an end to end network is critical in managing and maintaining accurate inventory. It simplifies the entire product lifecycle from planning and deploying to retiring or decommissioning network elements. Telecom Network Inventory (TNI) Washington Release enables service providers to
- Have a visual topological representation of an entire end to end network to aide in the collection of network equipment and connectivity within TNI
- Enable the capability of visualizing multiple topologies that can be analyzed on a canvas
- Facilitate the design and planning process by simply selecting the equipment and connectivity
Additional information can also be found in the ServiceNow docs page:
Automating Network Topology with Workflows
The ServiceNow Washington release brings a simplified network topology implementation by providing a Network Viewer capability that allows customers to search, filter, and select existing topologies that can be displayed in the topology diagram which are based on out of the box demo data.
There are several methods of creating topology that will be explored. Network topologies can be created using the Design & Assign change model which is the recommended approach. Topology models can also be created manually but that is not a recommendation. The following process is to be followed when creating manual topologies:
- Create new network topology (cmdb_ci_network_topology) from available network topology models
- Create CI relations between network topology and:
- Network site – connects::connected by
- Equipment (as node) - contains::contained by
- Physical connection or logical connection (as edge) - members::members of
- Make sure all edges associated with the topology should have the corresponding nodes associated with the topology too.
There are several methods of creating topology that will be explored in the sections that follow.
Topology Overview of a Network Campus Example
An example topology overview is below where a single customer owns several network sites that are geographically distributed in a campus network scenario. In the example there is a linear topology depicted by the blue route together with a ring topology shown in red. The entire campus connectivity can be depicted with having the appropriate topology.
Campus network topology example with geographically distributed network sites
Topology Data Model
A new data model has been developed for the implementation of network topology within CMDB. The following are the new classes created:
Network Topology (cmdb_ci_topology): Represents the grouping of the network elements such as nodes (equipment), edges (connections), and termination points (interfaces), how they are organized and connected to each other.
Network Topology Root Node (cmdb_ci_network_topology): Acts as an indicator if wheather a node is a root node. This is not a CI table (not extending from an a CMDB CI table). This model can be extended to be extended to any CI. However the recommendation is to extend it to cmdb_ci_site, cmdb_ci_hardware (to relate all the hardware equipment), physical connections and logical netwonnections.
Topology Model (cmdb_ci_topology_model): A product model is extended to cmdb_ci_topology model which is further exteneded to create network specific topology model (cmdb-ci_network_topology).
Network Topology Model (cmdb_ci_network_topology): This model can be extended to be extended to any CI. However the recommendation is to extend it to cmdb_ci_site
Topology Data Model
Implementing Network Topology within ServiceNow
- To see the Topology View navigate to the Telecom Network Inventory Workspace
- From the List Menu, under Inventory > Network Topology has been added
- Existing demo data exists within Network Topology. Exploring a Ring topology that is part of demo data is depicted below where you can see the name of the topology on the left hand side. The infrastructure relationships are seen on the right hand side which also includes logical connections when you scroll down. The dependency view can be seen by clicking on the Dependency View that can be found toward the top of the window.
- Once in the dependency view, Click on the Network Topology Root to see the root table entry – in this case the root node is NS4/ASTR 9006/0
- Below is the dependency view of the root node.
- To simplify the topology, a new feature has been created called Network Viewer. Network Viewer can be accessed by clicking on the new icon on the left had side indicated below. The desired topology can then be selected from the drop down menu.
- The below depicts the rendering of the topology. The highlighted node icon is larger than the rest since it depicts the root node.
- The connectivity will also be displayed. If there is only a single connectivity the name will appear. For multiple connectivity, the count will be shown in the topology.
- By clicking on the “i” on the right hand side, the related information will be displayed for each node by clicking on the node.
- By Placing the curser over the node, all related logical connections related to that node will be highlighted
- The related information will appear for each element on the topology by clicking on it.
- The related information cards for all the interfaces will also be displayed when clicking on the interface within the topology
- The details of each interface can also be explored by clicking on the three dots on the right hand side and then clicking on details.
- The entire topology can be highlighted when clicking on the name at the top of the page
- When clicking on view details, the logical connection details are pulled up below.
- The topology re-allignment can also be done by clicking on the nodes and dragging them to the desired location
- Can click on Fit to screen by clicking on the first icon below
- Can click on refresh (second icon) to return topology to original format
Defining a New Network Topology
Defining a new topology is available by a simple out of the box template.
From lists navigate to > Changes > All and select NEW
There is a new out of the box template “Design & Assign Topology” available and can now be selected
- Select SAVE when the template appears
- Once the template is Saved, the tab Change Task appears
- Click on the Change Task tab and then click on the Task Number to go to the topology Design and Assign form.
- The following can be completed as an example:
- Name: NS4-NS5-NS6 Linear Chain01
- Topology Model: Ethernet Linear Chain
- Bandwidth: 10 Gbps
- Topology Sites: Network Site 4, Network Site 5, Network Site 6
- Topology Nodes: NS4/ASR 9006/0, NS5/ASR 9006/0, NS6/ASR 9006/0,
- Filters the nodes belonging to this particular location
- Root Node: NS4/ASR 9006/0
- Topology Connection Type: Logical Connection
- Options include: physical connections, logical connections
- Topology Connections: NS4/NS5/ENET Section/10Gbps/7; NS5/NS6/ENET Section/10Gbps/8
- Click on Submit
- Once submitted, the topology will be successfully created the NS4-NS5-NS6 Linear Chain01 topology
- To View the topology, click on the topology icon and the newly created topology will appear.
- The two topologies can be added
- The topology can be highlighted in the viewer by clicking on one of them at the top of the page.
Supported Upgrades
Below is a list of supported upgrade paths.
|
Base Version |
Target Version |
Upgrade Impact |
|
Utah |
Washington |
Topology UI supported in Utah after TNI bundle upgrade to 8.0. app-enterprise-content and sn-topology-map are new dependencies required. app-enterprise-content needs to be installed before app-ni-core upgrade. |
|
Vancouver |
Washington |
Topology UI supported in Vancouver after TNI bundle upgrade 8.0. app-enterprise-content and sn-topology-map are new dependencies required. app-enterprise-content needs to be installed before app-ni-core upgrade. |
