Intent based Networking IBN Guide

Intent-Based Networking (IBN) is a method of managing the settings of your network. Although a network is made up of a group of endpoints and servers linked together by cables joined by switches, there are many other factors involved.

IBN systems use the same infrastructure but implement traffic management tweaks through software, Intent-Based Networking Software (IBNS).

You will get a different performance out of your network depending on the types of applications that you run. This is a well-known experience in the networking sector and that’s why there are a lot of different strategies that are available for traffic management. Traffic shaping enables a network manager to get the best performance out of limited resources.

Network capacity planning

Capacity planning is complicated. As a rough cut, you just need to work out how much traffic each software package generates, how many endpoints that device will be installed on, and what server-based systems will be accessed by which endpoints. After that, you add on a margin for growth and then you have your total network capacity requirement.

Things get a little more complicated after that point. Some areas of the network might get more traffic than others. Capacity planning usually looks at the LAN in isolation, and many network managers tend to forget about their wireless access points and how much extra traffic they can channel through to the cabled network.

As you progress in the capacity planning task, you need to start examining the capacity on each segment of your network and then on each link. Once you have checked the capacity on each segment, you need to examine end-to-end routes across the network. Once you have set up the network or extended it, you need to keep checking on the capacity to ensure that you don’t get unexpected traffic patterns.

Capacity planning is a very time-consuming and complicated task. It would just be a lot easier to get a tool to do all of that for you. Fortunately, there are traffic management systems that monitor network flows and advise on adjustments that need to be made. That’s where intent-based networking software can really help.

Network topology

Networks are made up of switches that link groups of endpoints and links between switches. Fortunately, traditional businesses group related workers together in one office. So everyone that works on financial functions are all sited together in one office with an Accounts Department sign on the door.

Network topology

Generally, people interact more with others in the same department, so a switch linking all of the PCs in the Accounts Department will be able to manage all of the local traffic without reaching out to other parts of the network. Localized utilities also tie into this segment plan. For example, there will probably be a printer in the Accounts Department and people working in that office are going to want their outputs to come out nearby and not on the other side of the building.

Unfortunately, recent developments in working practices and business services have reduced this localized priority for traffic.

If the business uses collaboration systems, such as Slack, all teamwork traffic is going to need to go out of the building onto the internet and then back again so that one person can chat with a colleague sitting at the next desk. So, much of the natural proximity assumptions for communications no longer apply. Businesses that include wireless utilities and allow BYOD are even harder to plan for. Departments that include remote workers and roaming staff who are always out in the field have network traffic zooming around all over the place.

New working practices and the attraction of internet-based services mean that it is very difficult to plan capacity precisely, segment by segment. IBNS addresses these issues.

Traffic shaping

Not every business can afford to provide infinite capacity on the network. No matter how much infrastructure you put on, you can still find that some switches get overloaded while other parts of the network have spare capacity.

Traffic shaping measures alter the way that switches deal with different types of traffic. This takes into account the fact that some traffic is more urgent than others. Emails don’t have to arrive immediately: a few seconds delay on their arrival makes almost no difference to most office workers. However, a few seconds delay on a VoIP call ruins the point of the service.

Interactive applications, such as voice and video applications are more time-sensitive than others. While people don’t want any of their activities to be delayed, they won’t notice if a file upload takes a few seconds more than it could have done but they will notice if their video conferencing screen breaks up.

Typical traffic shaping measures include the creation of virtual LANs (VLANs) and queuing on each switch. VLANs tag the traffic generated by specific applications so that the switches and routers on a network can recognize a stream and treat its processing separately from all other traffic. The result of this technique is that the traffic seems to be running on a separate circuit even though in reality this other system is really running over the same resources that all other traffic uses.

There are a number of different types of queuing systems but they all rely on the strategy of holding up some traffic for the benefit of improving the speed of other traffic.

Traffic shaping allows budget-conscious network managers to put off expanding the network infrastructure when traffic demands increase. Networks that have uneven demand can’t be improved infinitely. Ultimately, topology will need to be adjusted in order to expand physical capacity in some areas. However, reduced strain in one part of the network can free up resources that can be redeployed in other locations.

Traffic management is an ongoing task because improving performance in one part of the network can overload switches in other locations. This is simply because the potential demand on that device had previously been held off by a block on the previously congested switch. So, fixing a problem in one area of the network can just create more problems elsewhere.

The knock-on effect of each change made anywhere on a network means that traffic patterns need to be constantly monitored. Adjustments made to improve performance in one area might need to be reined in a little in order to head off disaster at other switches.

Most network traffic flow monitors will show different rates of demand on the network but these rarely implement solutions to traffic problems. Intent-based networking software identifies resource requirements and automatically implements traffic shaping measures to cope with that need.

​Intent-based networking software

To properly understand what intent-based networking software does, it helps to think of an analogy. Think of a stereo system that has a graphic equalizer. It lets you turn up the volume on one part of the sound spectrum individually. There are usually many individual ranges that can be tweaked up and down relative to each other. Improving the bass on the stereo is a little like prioritizing one type of traffic on a network.

You could sit and fiddle with the graphic equalizer all day and once you’ve got the levels right for one type of music, you put on another of your favorite tunes and discover that the sound balance is all wrong and so have to start the process all over again. Fortunately, most graphic equalizers also have presets. With the push of a button, you can have all of the settings altered to suit Hip Hop music, and then when the next tune comes on, switch over to Folk, Orchestra, or whatever type of music that track falls into.

Intent-based networking software acts like those sound presets on a graphic equalizer. It communicates with switches and alters the traffic shaping methods used by them all to suit the type of traffic that you expect to get on your network.

​More about business intent

The “intent” part of intent-based networking doesn’t refer to the industry of the business that the network serves. Rather, this word refers to a type of traffic. One example is file transfers to cloud storage, another is the use of VoIP for the office telephone network.

As a busy network manager, you have probably attended lots of meetings with key users and you know exactly what applications are important to them. You have probably negotiated a service level agreement with each department so each knows the quality of service to expect on each of the applications that they prioritize.

Different parts of the user community want different applications. So, you can’t just set the entire network to prioritize one type of traffic. Different parts of the network will serve different user requirements. Therefore, it is necessary to vary traffic shaping measures across the network.

Not only is the intent different from place to place, but it can also vary over time. If you do bulk backups overnight, your traffic priorities are going to be different after hours than they are during office hours. If your users tend to have most of their meetings in the afternoon and include staff on other sites, then the afternoon will need a greater prioritization for video traffic while the network will experience a heavy load of email and productivity suite traffic in the mornings. IBNS makes interpreting business requirements (“intent”) into traffic shaping measures and altering those settings for different requirements per location and per time slot.

​Exceptional events

IBN software is very useful for dealing with infrequent, or one-off events that can radically alter the network’s traffic priorities for just a short space of time. For example, a CEO might announce that she is going to make a major announcement about a forthcoming merger and take questions from all of the staff. This would require a temporary alteration to the settings of all switches on the system to expand the bandwidth available to a video VLAN. Once the meeting is over, all settings can go back to how they normally operate for the business.

Making constant changes to the network’s traffic management settings to account for different traffic profiles throughout the day would be very time-consuming. However, that is why it is essential to buy specialized IBN software if you want to implement this strategy.

​Intent-based networking vs software-defined networks

You might be thinking that the description of an intent-based network sounds a lot like software-defined networks (SDN). Up to a point, you are right. Both IBN and SDN systems reinterpret existing infrastructure and present a virtual view of the network to the operator.

There are a number of important attributes that make IBN different from SDN. The main difference between the two is that SDN manages the settings of a network device in isolation, ensuring that it hits its optimum performance. The IBN is adaptable; it doesn’t have one single solution. It alters the settings of each device to ensure a flow of data over the network in accordance with the stated intent/policy of the business. The IBN software will constantly adjust device settings to ensure that the policy is achieved.

Intent-based networking software engages in a lot more activity behind the scenes. It performs all of the network management decision-making tasks that an SDN system would leave to a human operator.

​Adopting intent-based networking

If you are interested in intent-based networking, the chances are that you have already looked into traffic shaping measures and tried implementing them. Intent-based networking is ideal for businesses that don’t want to spend more than necessary on network infrastructure. A business that has a very large IT budget can afford to provide excess capacity on all parts of the network that will cater to all eventualities.

Network managers who have already implemented traffic shaping have a good idea of the business requirements that form the definition of “intent.” There will be variable intent required for the network. The first step in taking on IBN is to document all of the intents that you want to cater to.

​Implementing intent

As with most areas of IT, intent-based networking has its own terminology. The bottom line is that you need to get a stated business requirement translated into traffic shaping measures. Here are the stages you need to look at:

  1. Intent: Network performance goal
  2. Policy: Aims that indicate successful goal achievement
  3. Profile: A stored policy implementation
  4. Activation: Running a profile to change switch settings
  5. Analytics: Goal achievement tracking
  6. Adjustments: Maintenance of performance goals
  7. Assurance: Confirmation of successful goal achievement

The diagram below shows how these processes fit together:

​Implementing intent process diagram

The key task for a network manager is to interpret the business intent into a quantifiable policy. Administrators that have already set up security monitoring on a network will be familiar with the concept of “policies.” This task is very similar to the creation of security policies. In fact, security monitoring is an intent that you are likely to want to implement as part of your IBN strategy.

The amount of guidance that the IBN software offers is the key variable that distinguishes one IBN software package from another. The user interface and ease of use is the main factor of the IBN software that will influence the decision over which system to buy.

Operating intent-based networking

The purpose of intent-based networking software is to implement IBN for you. The full lifecycle of the network management strategy is shown in the diagram below.

Lifecycle of the network management strategy diagram

Monitoring network performance is an integral part of IBNS packages. Although network managers are familiar with network performance monitoring systems and network traffic analyzers, all network monitoring should be performed through the IBN software.

The intent-based networking software will automatically adjust switch settings to ensure that performance expectations are maintained throughout operations. Therefore, direct intervention by a human administrator would impair the execution of the IBN policies rather than improve them. If it transpires that the IBNS is not adjusting network settings appropriately, it could be that the policies need to be redefined.

If adjustments to the policies don’t improve performance then the IBNS is probably not as good as it needs to be. This is why it important to get an IBN software package that allows a trial period. The purpose of IBNS is to automate all traffic shaping measures. It either works or it doesn’t. There is no performance scale for the IBNS industry, so each buyer needs to make an individual assessment of each available package.

​Assessing IBN software

Adopting the IBN strategy means going to full traffic management automation. If you expect to be able to monitor traffic and intervene, you probably should go for this route. Once policies have been set up as profiles, you would alter the implemented traffic strategy by instructing the IBNS to implement a different profile, which can contain a combination of policies.

So, you will be handing over a lot of control of your network to the IBNS package. For this reason, the decision over which IBN software to buy should not be made in a hurry. Ensure that the package you opt for is able to provide the right mix of simultaneous policy implementation that you need. If your network traffic priorities change according to the time of day, ensure that the software you choose has a timeline option that lets you set schedules for when different policies should be applied.

Fortunately, the leading providers in the IBNS field are very well-respected brands with a solid competence in networking technology. Make sure you get a trial of the software so that you don’t end up paying out for a system that doesn’t really meet all of your needs. Systems that don’t offer a free trial still give you a grace period for buyer’s remorse that usually allows you to claim a full refund within 30 days of purchase.

​Intent-based networking software

Intent-based networking software is a fairly new concept and requires a very comprehensive software package. So, there aren’t many providers in the field right now. However, as the appeal of IBN increases and more businesses discover the strategy there will be more software houses entering the field.

Here is our list of the best intent-based networking software packages that you should consider.

  1. Cisco Intent-based Networking Cisco Systems is the world’s largest producer of network devices, which puts them in a good position to provide this very good family of products. Cisco has a special IBN package that is tailored towards data centers and another for in-house networks that includes AI-based services.
  2. Juniper Networks Self-Driving Network Juniper Networks is still developing its intent-based networking service. It has plans to add automatic system adjustments to its SDN package to expand into IBN software.
  3. Apstra Operating System A network design and management platform that helps data centers manage the created network on intent-based lines. This platform is vendor-agnostic and can manage switches from a list of providers, including Cisco and Juniper Networks.

​Alternatives to internet-based networking

If you think that implementing IBN involves too much of a loss of control and you would rather use a network management system that allows you to use your experience and skills, you could consider implementing a software-defined network instead. If you just want to gain greater insight into traffic flows on your network and implement traffic shaping measures, you could consider using a network traffic analyzer.