When you’re planning a major grid modernization project and an associated communications network to support it, the challenge can lie in planning your network capacity. How do you accurately determine your needs into the future to ensure you don’t severely impact your operations?
Here are some of our tips on where to start:
1. Establish a benchmark
Your first step is to gain an understanding of your network. Look at:
Your network topology and any short and long term expansion projects;
Your available capacity/bandwidth across key points in your network;
Your current capacity utilization at those key points;
Applications running across your network and their capacity and latency demands;
The capacity needs of any new equipment/devices/software you intend to incorporate into your network in the future.
This benchmark is a measure of your existing network’s performance with a view to understanding how any future expansion is likely to impact performance.
2. Build an inventory & map it
As part of your benchmarking you will need to create an inventory of all your network equipment. Specifically, you will need to estimate the data throughput of each piece of equipment in your network and of your network links (uplink and downlink rates). See the example below for a table which will help you to build your network inventory:
Map these assets on a network map so you can easily see how many devices each link is serving and how many hops your data or voice traffic needs to do to get across the network. Some Network Management tools will incorporate LLDP (Link Layer Discovery Protocol) to automatically map the assets on your network.
A network management tool may also offer the option of color coding your data usage, allowing you to see where you are likely to experience congestion or points of failure in the future.
3. Ascertain peak vs average usage
You now need to gain an understanding of your data usage across your network at different times to determine how much of your existing capacity you actually use and on which activities.
Through monitoring your network activity over a pre-determined period of time, you will be able to highlight your peak times each day, week and month. There are a number of “net flow” tools on the market which are designed to capture real time peak and average usage statistics and identify potential bottlenecks.
You can also monitor which applications you are running at those times in order to work out if you could be operating your existing network more efficiently (i.e. scheduling applications to run at different times). This is a key step to consider prior to adding in any new network equipment (which will undoubtedly increase the total amount of data traversing your network) as you may be able to regain some capacity prior to embarking on your expansion project through prioritizing network activities.
During this stage, you should also look to calculate your percentage of packet loss and determine whether the rate is impacted during peak times or not. You can then check whether the packet loss undermines your capacity demands, requiring some further RF system optimization.
4. Determine your future demand
After gaining this valuable information about your current network operations, you can attempt to estimate your future capacity demand.
To do this, you will use the manufacturer’s specifications for bandwidth for any new hardware or software you will be adding to your network.
If the equipment does not have the bandwidth specified and the manufacturer cannot provide you with this figure, you can set up a bench test using an evaluation piece of equipment. During this testing, you will be able to measure the bandwidth usage and then extrapolate the data outwards. For example, if you are going to have multiple new endpoints in the network, simply take the data generated in the trial and multiply accordingly.
In the instance of adding new endpoints, another route to determining your new bandwidth requirement is to record the amount of traffic between existing endpoints and base units for each type of application you intend to be running. You can then take the data outlining your traffic and multiply it by the number of endpoints you intend to add to your network.
5. Plot your capacity
Now take your network map and add your estimated additional bandwidth requirements to your peak and average data usage across the network.
Pay attention to:
your maximum capacity currently available across all of your links;
the areas of your network with the lowest capacity, and;
the adjustment required for your packet loss.
At this point you should have some idea of whether your network can cope with your future demand.
6. Aim to alleviate congestion
Via the usage statistics logged on your network map, you may note areas of particular congestion which require some input.
Congestion could be alleviated here by increasing your bandwidth capacity in these areas through:
The purchase of new communications equipment;
Rearranging your network configuration to balance the load across the network;
Scheduling applications to run at different times to reduce the load at peak times (e.g. AMI traffic could be run during off-peak hours);
Use of more bandwidth efficient, lower latency radio protocols such as UDP/IP vs TCP/IP;
Prioritizing traffic into high and low priority and asserting the appropriate QoS rules.
In a wireless network, at times too many nodes can be attached to a base station. In this instance, it is important to rework the network coverage design to create a lower number of endpoints per sector, thereby better balancing the load across the network.
Downtilt and reducing the power at a highly utilized sector will naturally allow the endpoints connecting to that sector to attempt to adjacent cells instead, helping to average out the capacity loading on all the sectors and alleviate congestion.
If you are operating in a bandwidth-constrained environment, you should also look at incorporating advanced communications technologies which can improve your data throughput. These include MIMO, full duplex communication, sophisticated data compression techniques and data acceleration protocols.
Mimomax has the in-house expertise to help you to accurately plan your new network or network expansion. Our advanced radio solutions can also integrate with a range of network management and flow analysis tools including products from companies such as Manage Engine, Solar Winds and Paessler.
If you would like one of our team to contact you to discuss your plans, please click here.