Please note that background Information can be found in the following Blogs:
- 5G Introduction: https://www.servicenow.com/community/telecomm-blog/servicenow-5g-introduction/ba-p/2738678
- Defining 5G Services: https://www.servicenow.com/community/in-other-news/defining-5g-services/ba-p/2741387
Mobility Service Topology
The key to modeling a 5G network is to view the service from the ground up in a layered approach. From an inventory modeling, 5G services run on top as an overlay with respect to the resource underlay, and the transport. It is critical that an inventory system can model 5G services as 5G network slicing will become more prominent in the near future where network capacity will be dedicated to slices of varying SLA requirements. Having the capability to know resource availability in each network slice is essential in automating network slicing instantiations.
Figure 23: Topology network view of a mobile network
As part of the network overlay, delivering a 5G service requires the entire network definition which include:
- Vendor specific information such as specific configuration files
- Service specific information that is designed by the end user (i.e. bandwidth requirements, latency SLAs etc) that are part of a blueprint (i.e. for slicing) and policies defined by the enterprise or end user.
- Deployment or foundational information that is specific for the deployment of that particular service being requested
- The Underlay of resources that are needed to support the service from a VNF/CNF/PNF perspective.
ServiceNow Telecommunications Network Inventory
ServiceNow’s Telecommunication Network Inventory (TNI) is a critical component in being able to federate the service overlay, the resource underlay (Physical network, VNFs and CNFs), and the transport sub networks. Having a comprehensive, multi-layer view enables CSPs not to miss a beat in the entire lifecycle, from:
- network design and assign,
- to planning and build,
- to network deployment and operations, and
- to product and service ordering, fulfillment, and assurance
TNI unleashes capabilities that provide real-time visibility, flexibility, and control by delivering actionable insights along with providing a granular understanding of the end-to-end network. The capability of providing visualization across any service, any infrastructure and across any technology is fundamental to deploy new services, provide service assurance, security, closed loop automation, and network optimization. Having a consolidated inventory system enables CSPs to have complete control over their own networks enabling them to see through their network complexity to provide improvements into their network operations which in turn helps to guarantee end customer quality of experience. All this while reducing CAPEX and OPEX while paving the path toward autonomous zero touch networks.
ServiceNow’s TNI provides complete lifecycle management of a network on a single platform and with a single Configuration Management Database (CMDB) starting with an accurate and real time inventory system. TNI is fundamental in driving near-real time network visibility, data accuracy, and product, resource, and service inventory to properly manage and maintain an end-to-end network. Exciting new innovations thrive on accurate data to properly design, plan, build, operate, and maintain a dynamic multilayer network. Having a platform that seamlessly provides inventory, order management and service assurance while automating workflows to save on operating costs is fundamental in driving innovation—from the data center to the edge, and far edge.
Best Practices for gNodeB CMDB Modeling
Business application will be table which will be capturing the type of Managed Network Function. A managed network function/Business Application is required to extend a dedicated CI class for a managed function to define different managed network function (for example for RAN would be DU, CU-CP, CU-UP and for CORE would be the 5G Core Network Functions like AMF, UPF, SMF etc). Business Application CI Class will be the parent and will record all the characteristics for that specific managed network function as per the 3GPP specifications mentioned above.
There will be an application service CI that will be deployed for every instance of a managed network function along with all the associated characteristics. Each instance of a specific Application Service (i.e. Managed Network Function) will be related to the parent class of Business Application. There will a record application
For each instance of a managed network function, there shall be a record in application service. These application service shall be related to underlying infrastructure by creating a relationship to the network interface card. The Network interface will be capturing the Logical Interface which will be assigned to the respective managed Network function.
Below is an example of how the Virtual and Logical Connectivity proposed with the implementation.
Figure 24: gNodeB Modeling Best Practices for the Virtual and Logical Components.
For additional information please see:
Best Practices for Modeling a Mobile 5G Network is described in the following sections. There are several steps that should be followed in order to implement the network inventory within TNI which include:
- Creating the Businsess Application for each Network Function
- Create Application Services for each Instance of the Network Function
- Relate the Business Application to the Application Service
- Create Pack Attribute Table for the specific network function and relate the Pack table to the Application Service (Next Blog Discussion)
- Create a Network Interface and Assign is to the specific xNF
- Creating Logical Connections between the End Points of the Managed Functions
- Create the relationship between the Application Service and the Logical Interface
Each of the above steps are described in the following sections. Network Inventory will also have several out of the box capability for instance, below is a list of what is supported.
Business Applications available out of the box include:
- gNodeB, DU, CU-CP, CU-UP, AMF, SMF, UPF
Application Services that are available out of the box:
- gNodeB, DU, CU-CP, CU-UP, NRCellCU, NRCellDU, AMF, SMF, UPF
Pack tables that are available out of the box include:
- pack_3gpp_gnb_du_function
- pack_3gpp_gnb_cu_up_function
- pack_3gpp_gnb_cu_cp_function
- pack_3gpp_gnb_amf_function
- pack_3gpp_gnb_smf_function
- pack_3gpp_gnb_upf_function
- pack_3gpp_gnb_ep_rp_function
- pack_3gpp_gnb_managed_element
- pack_3gpp_nrcelldu
Figure 25: Example Unified Map View of the defined Network Functions
Created the Business Application for each Network Function
- Additional Information can be found here: https://docs.servicenow.com/bundle/vancouver-telecom-network-inventory/page/product/tmt-telecom-netw...
- Navigate to ALL > CSDM > Design > Business Application
- Select New
- Fill in the from with the required information (Example Data Provided Below)
- Name: DU_xNF_Best Practices
- Application Type: SaaS
- Install Type: Cloud
- Description: Distributed Unit Network Funciton
- LifeCycle Stage: Operational
- Lifecycle Stage Status: In Use
- Navigate to the Owners tab and change the following:
- IT Application Owner: Shree Sharma (Example)
- Submit the changes
- All the above steps should be repeated for each xNF
Create Application Services for each Instance of the Network Function
For additional information, please follow the below link: https://docs.servicenow.com/bundle/vancouver-telecom-network-inventory/page/product/tmt-telecom-netw...
- Navigate to ALL > CSDM > Manage Technical Service > Application Service
- Select: New
- The following form should be completed, below is an example data
- Number: Autogenerated
- Name: DU_MtL_001_xNF_Best Practices
- Environment: Development
- Operational Status: Non_operational (Lab Environement)
- Description: Distributed Unit Network Function for Cell Site Mtl 001
- Navigate to the Set Relationships/Business Application tab.
- Business Application: DU_xNF_Best Practices
- Click Next.
Click Choose a Method to populate the application service and Complete the following fields in the form. Below is just an example.
- Service Population Method: Manual
- Class: VMWare Virtual Machine Instance[cmdb_ci_vmware_instance]
- CI: CA VM 01
- Click Next.
- Click SAVE
- Click Next.
- Validate the previous section and that you see the relationship Consumed by:: Consumes. The relationship from the Application Service to the respective Business application is automatically created for you based on what you completed in the previous section (by adding the business application). As in figure 24, in Application Service representing a DU needs to be associated to the respective Business Application of type DU
Then click on Done.
Navigate to Workspace > Network Inventory Workspace > Services > Application Services
- Locate the appliacation Service: DU_MtL_001_xNF_Best Practices and open the form
- Click on Set Inventory Attribute UI Action
- Note if the Set Inventory Attibute is not present, then they have already been set and can skip to the next section.
- This step ensures that the inventory is part of TNI entity – essentially managed by TNI entity table
- Complete the below fields in the form:
- Role: 5G
- Type: RAN
- Click on Save
Create a Network Interface and Assign is to the specific xNF
Additional information can be found in the following link:
The logical interface between two network functions will be created and related to the application service.
- Navigate to Workspaces > Network Inventory Workspace
- Navigate to ALL > Telecom Network Inventory > Interfaces
- Select NEW
- Complete the following fields in the form (Example Data)
- Name: F1U_Best Practices
- Equipment: DU_MtL_001_xNF_Best Practices
- Model ID: EP_F1U
- Virtual: Yes
- Name: F1U_Best Practices
- Right Click at the top of the form and click save
- Click on Add CI Relationship (Click on the “+” sign – if you hover over it, Add CI relation will appear as well)
- In the following form, the end points now need to be defined.
- Suggested relationship types: Implement End Point To (Parent)
- Class: Mapped Application Service
- Name: DU_MtL_001_xNF_Best Practices
- Click on Run Filer
- The Configuration Item is then selected and the relationship to this CI needs to be added by clicking on the “+” symbol
- Click on Save ans Exit
- Click on Set Inventory Attribute UI Action
- The Following form needs to then be completed by adding the following:
- Type: ENDPT
- Click on Update
- Click on Save and Exit
Creating Logical Connections between the End Points of the Managed Functions
Additional information can be found in the following link:
There are two ways in which a Logical Connection can be created. We have the out-of-the-box capability via Change which will be referred to as METHOD 1 and of course creating the logical connection via the Logical Connections form which will be referred to as METHOD 2.
METHOD 1
- In the ServiceNow® Platform UI, Navigate to All > Inventory > Change
- Once There Click on New
- Once the new window with the out-of-the-box Change requests appears, Select Create Logical Connection and then select NEXT at the bottom right hand
- The Create New Change Request Screen will Appear and then Select SAVE
- The next window will appear. Select the Change Task tab shown below and click on the new change request that was just created.
- Complete the form
- Name: F1U_Best Practices -1 to F1U_Best Practices -2 Peer to Peer
- Port A: F1U_Best Practices -1
- Port Z: F1U_Best Practices -2
- Click on Save
METHOD 2
- In the ServiceNow® Platform UI, Navigate to All > Inventory > Logical Connections.
- Top Right hand corner, click on New to create a logical connection
- Complete the following form by adding some of the pertinent information below (additional details can also be added)
- Name: F1U_Best Practices -1 to F1U_Best Practices -2 Peer to Peer
- Port A: F1U_Best Practices -1
- Port Z: F1U_Best Practices -2
- Click on Set Inventory Attributes (Top Right hand corner)
- Complete the following fields in the Form.
- Role: 5G
- Click Update
- In the List View of the logical connections, click on and open the one that was just created (F1U_Best Practices -1 to F1U_Best Practices -2 Peer to Peer ) to be able to now add the CI relationship
- Click on the “+” in the middle of the form to be able to add the CI relationship
- The Form to add the CI relationship now needs to be created. Suggested fields to be completed can be found below:
- Suggested Realations Types: Terminated (Parent)
Search Fields Include:
- Class: is Network Interface and
- Name starts with F1U_Best Practices -1 or
- Name: F1U_Best Practices -2
- Click on Run Filter
- Select Both and add relationship
- Click on Save and Exit
Conclusion
Stay tuned for additional posts. The next post will be Associating packs and Params to Application Services.
