OSS Sandpit – Fixed Wireless Network Inventory Prototype

This article provides a tutorial for building Fixed Wireless (FW) Network components into the inventory module of our Personal OSS Sandpit Project.

This prototype build includes components such as:

  • A fixed wireless core network
  • Radio Links across licensed and unlicensed (5 GHz and 24GHz)
  • Line of Sight analysis of each Radio Link and Viewshed
  • Fibre links (including cable management)
  • Tower Management
  • Routing and Switching
  • Layer 2 and Layer 3 service modelling (eg VLANs, VPLS tunnels, etc)

This Fixed Wireless prototype can be summarised as follows:

The primary link is at the bottom of the image (ie 101C – RICH – SWIN – BOXH). The fibre leased-line (101C – BOXH) is for resilience only.

The main intent of this network is to carry L2 services (between Customer Sites 90001 and 90003) and L3 services (between Customer Site 90001 and DXM1). This is as depicted in the service model diagram below:

We’ll revisit the modelling of these services later.

In this post we’ll describe the following use-cases:

  • Building Reference Data like data hierarchies, device types, etc
  • Performing Site Qualification and Line of Sight Analysis between locations
  • Creating Device Instances including buildings, towers, radios, etc
  • Creating Physical Connections between devices (eg radio links, fibre links)
  • Creating Customer Service Modelling 

 

Reference Data

Starting off with the data hierarchy, we had to develop some new building blocks (data classes) to support fixed wireless assets and new link types that allow us to quickly identify the differences in link types from high-level diagrams.

We’ve developed a custom data hierarchy as follows:

  • Country
    • Radio_Infra (to separate FW core network assets from other network assets)
      • Site (core network sites – 101C, RICH, SWIN, BOXH, SURH)
        • Buildings / Comms Rooms
          • Rack
            • Equipment
      •  Tower
        • Appurtenances (ie attachments to the tower)
          • Mount Groups (ie the frames / mounts that connect attachments to the towers / poles)
            • Equipment (including radio units)
    • City
      • Customer Sites
        • Devices (ODU / antenna, IDU, routers)

This required a few new templates, including Customer Sites and FW Core Sites.

Site Qualification and Line of Sight Analysis

Being a Fixed Wireless network, effective communications links rely on line of sight between radio units.

We used Google Earth for Site Qualification and Line of Sight. Here is the plan view of our small section of network:

But we need to ensure each of these legs if visible:

Here’s a view of the 101C – RICH link:

Here’s another view of the same link showing clearance above the MCG light towers:

Here’s the link from RICH – SWIN. :

Here’s SWIN-BOXH:

And finally SWIN – SURH:

All clear on the link analyses above.

For comparison, the following diagram shows the corresponding core network, including fibre links, in Kuwaiba’s Outside Plant Module:

The colour-coding of the links in the diagram above is as follows:

  • Light Blue = 5GHz Radio Links (unlicensed, approx 150Mbps)
  • Green = 24GHz Radio Links (unlicensed, approx 1.4Gbps)
  • Orange = Licensed Radio Links
  • Royal Blue = Fibre Links

The fibre links required fibre management using Kuwaiba as shown below:

Note: The viewshed functionality in Google Earth provides a useful approximation of line of sight from a given point. The green shading in the example below approximates the areas where coverage can be achieved from BOX-MNT-01 (the first mount on tower 1 at the Box Hill core site).

Device Instances

We then create the devices in Kuwaiba to build the prototype network model shown in the first diagram above. Not all devices are shown.

Here’s a partial rack view of the first rack at 101C:

We can also drill down into patch management within the rack as follows:

Tower Management

The following diagram shows a simulation of the tower at 101 Collins St (not actual), specifically showing the mount groups and other key attributes we’ve modelled in Kuwaiba:

Attributes such as elevation, azimuth and horizontal offset have all been identified from the Line of Sight Analysis done earlier in Google Earth.

Note that the attributes of 101C-MNT-01 are shows in the right pane below:

Physical and Logical Connections

There is quite a lot of patching and port mirroring required to create the connectivity between the core sites, customer sites and data centre.

The following diagrams show the three leased fibre lines (we’ve excluded fibre joints and splicing to simplify the scenario, but more details and screen-caps of cable management can be found in this earlier inventory article):

Fibre cable from 101C to BOXH:

Fibre cable from 101C to customer site 90003 (including identification of cable name in left pane):

A full trace all the way from Customer Site 90001 to the Data Centre (L3 service chain) is shown in the diagram below. Click to view in full size:

 

Service Modelling

Re-showing the second diagram above, you’ll notice that there are a number of important service points relating to the L2 (the red, upper path) and L3 (the blue, lower path) services offered over this FW network:

If you look closely at the diagram below, you’ll notice that all of these service points have been modelled into Kuwaiba for Customer 90001:

You’ll also notice the Layer 2 services have been expanded to also show service impact (ie which devices / circuits / cables each link in the service chain relies on). The full service impact is modelled for L3 services as well in this demo, but not expanded in the screen-cap.

We’ve also modelled the Fibre Links as Leased Line Services, including service impacts shown below:

Summary

I hope you enjoyed this introduction into how we’ve modelled a sample Fixed Wireless network into the Inventory module of our Personal OSS Sandpit Project. Click on the link to step back to the parent page and see what other modules and/or use-cases are available for review.

If you think there are better ways of modelling this network, if I’ve missed some of the nuances or practicalities, I’d love to hear your feedback. Leave us a note in the contact form below.

Read the Passionate About OSS Blog for more or Subscribe to the Passionate About OSS Blog by Email

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