Making Network Diagrams Better!

I have drawn, automated, consumed and reviewed many, many 1000s of network diagrams in my time. When I started my first company in 1989 as an independent network troubleshooter the first question was always - can I have a copy of the latest network diagram? Rather than reverse engineer what others already knew while the network was in trouble, it was quicker and simpler to ask. The answer was almost always negative and in hindsight the lack of a diagram made it difficult for them to identify the problem areas. So I would create a drawing for my own use which enabled me to identify and resolve the issues. The diagram helped me interpret error conditions and decide the next steps as I deployed packet analysers and SNMP management tools. I always passed across a copy of my diagram knowing that it probably wouldn't be updated. When that business was sold in 2004 I decided that solving the network diagram "problem" could keep me busy for ever (19 years so far). My research found the same issues applied to other types of IT diagrams - floor plans, rack layouts, architecture views, VLANs, Cloud, ITIL service maps, data flows, etc.

As with any schematic or drawing, a picture shows dependencies better than a 1000 words. But when there are many 1000s of pictures to create, update and distribute every week then method and discipline is important - so I became a bit OCD about process and consistency.

Don't version control diagrams as how can you tell what and where the latest version is?

So a couple of tips from me and some differences to accepted thinking or current methods.

1. A diagram explains a view of data. A network switch will be in rack layouts, VLAN, network, resilience and other diagrams - so use an inventory of devices with configuration data to help create and refresh diagrams that have infrastructure components. Use the same method for connections - such as an inventory of links with data such as ports, IP addresses, cable IDs, VLANs, MAC addresses etc. We use MS Visio as it can link to data in Excel manually, or be used as an automated reporting system on a database (the approach with our AssetGen Connect software).
2. Use the best symbol or shape that helps diagram understanding. A physical shape is good for rack layouts, but too detailed for an architecture maps. Logical symbols for switches and routers make it easy to understand function in a diagram. So have templates or symbol sets for different drawing types and levels of detail. Don't assume that standard Visio shapes from Microsoft or a manufacturer will work well, as often they have extras that complicate things and may need to be removed.
3. Keep diagrams as uncluttered as possible by letting consumers click on symbols for more data, using layering techniques, or drilling into to other information. A network topology diagram may show switch links and configuration details, so why not drill into the switch to see the server connections, location, or the patching path through the cabling to the switches. Investigate the use of Visio data graphics where users can change the data displayed on a diagram, or colour code old OS versions - if only you knew it existed. It enables a single diagram to meet many information needs including dashboards on status, power, risk, etc.
4. Don't version control diagrams as how can you tell what and where the latest version is? Version control is good for projects where different versions reflect changes in requirements or configurations. But for general use if you keep the same file name and embed a refresh date on a diagram, then users can use their most recent menu to open up the latest network diagram, no matter what the version is. In our automated approach we archive old versions with the latest overwriting the original, as trying to maintain version numbers for 1000 different network diagrams that are changing occasionally. but refreshed every week is wasted effort. If you want an audit trail then use the database that created them as it is better suited to change reporting than diagram history tabs or tables. Remember a device may be in more than one diagram - so changing data once could refresh many diagrams. Try manually checking lots of diagrams for consistency of data with multiple tabs on a slow VPN link! There are more enjoyable ways to use up lots of time - holidays, parties, making a guitar, etc.
5. Ensure access to diagrams is controlled and appropriate. A network diagram makes it simpler for anyone to understand, but we don't want everyone to see sensitive information. Follow organisational policies for file / folder access, sharepoint, internal portals, redaction of data, etc. For instance, we developed a Visio utility that enables removal of IP addresses, contact details and other sensitive data from diagrams and shapes. So you can have a diagrams for use by the network team, then redact embedded data for sharing with customers and contractors. Saving as pdf or as web pages are other methods that enable different levels of viewing and control. Reduce the number of network diagrams in multiple email accounts by having up to date operational views that can be viewed on an internal portal (which is another reason to remove file versioning).

There are videos and webinars on our web site going into more detail of how data linking and automated diagramming work. Maybe you might want to spend less time manually creating and maintaining network diagrams?

Dave's Pet Peeves

I wish teams and companies would make life simpler for all by standardising their symbols / shapes for network diagrams. Attempts by the IT industry and manufacturers to have standard symbology are too cumbersome for time constrained network specialists. Resulting in us all trying to decipher what a symbol means. Communication is easier if the same language and pictures are used to convey information - so lets sort out the picture aspect. Invest a small amount of time and have standard symbol sets used within an enterprise. Problem solved!

For every type of diagram (then can be many 100s of types) there is often a good symbol to use. In the above graphic you can use a physical shape for rack layout as in the picture above, but if you want to show physical connectivity clearly then other options are clearer. For logical diagrams choose a common symbol that all can understand - in this case a firewall. It helps to have legends explaining the symbols, but even easier to have the symbol type embedded as data so you can click on it if you don't recognise it. It frees up diagram space if you don't have to have legends as well. Simple is always best!

Visio Corner

In this weeks Visio Corner we’ll cover some tips and tricks for using the Network Layout function in our Visio Utilities we give away for free. In Visio there are two ways to connect shapes with connectors in Visio, there is ‘Dynamic’ glue and ‘Static’ Glue. In simple terms if you are connecting shapes together you are using Dynamic Glue and if you are connecting connection points together you are using Static Glue.

Dynamic glue will move the end of the connector around the edge of the shape automatically to create the shortest length path whereas Static glue lines will stay fixed to wherever the connection point is placed.

The quickest way to connect up your diagram is using Dynamic Glue, as there is no need to create and place connection points on a shape you are using. However, it does not handle parallel connections between the same shapes well. Dynamic Glue tells each connector to find the shortest path possible between the two shapes, but if you have two connectors they could end up using the same path with one hidden underneath the other as in the picture below.

The way to avoid this is with parallel static connections, as they have different start and end points on the shapes. However the work does not scale up well. For a switch with 24 connections you would have to do almost 100 actions to connect it up! (24 connection points on the switch + 24 connection points on what you want to connect + manually linking the connectors to each of the 48 connection points = 96 actions).

To make it simpler and less error prone the ‘Layout Connections’ Visio utility removes the need to place connection points on shapes. If two shapes are connected dynamically, it will create connection points on both shapes and turn the dynamic connections into a static ones. It will evenly space out connection points on the shape to automate making parallel connections in a single click. (Often you would not know that there were extra or duplicate connections)

This will save you a lot of time as you layout a diagram for readability, reusing the layout utility as needed to remove and create connection points with even spacing between the lines.

Upcoming events

October 24th - Release date for the new AssetGen Cabling Architect system.

Our new product to support cabling designs and architectures for new installations in buildings and campuses.

October 26th??– Free Webinar, Planning and Managing Cable Infrastructure - Part 2 Detailed Design Details & Registration 13:00 UK 08:00 US EDT

In the second webinar on managing cable infrastructures, we look at optimising the detailed design and implementation of cabling systems. Both new build as well as upgrading or extending the current system.

October 26th??– Free Webinar, TIA TR-60.TSB Resourcing The Infrastructure People and Skills Details & Registration 18:00 UK 13:00 US EDT

Maintaining and evolving technology skills, as well as selective use of service partners is a key aspect of TR-60 Infrastructure Life Cycle Management. Changes to teams, roles and authority levels are inevitable with the potential to lose talent and not keep up with the skills required for long term management of ICT infrastructure.

I hope you enjoyed this edition of this newsletter, make sure you subscribe by clicking the button at the top of the page to keep updated on future articles and events.?

Square Mile Systems | AssetGen Visio Utilities