Software and Hardware Sizing

Five steps to specifying the right software and hardware

This chapter provides a guideline for choosing the right Genian NAC software and hardware. Specifying the right software and hardware is dependent on a number of factors and involves developing a usage profile for the users and the network environment.

Step 1. Identify the Total Active Devices Number for Software License

The license of Genian NAC Software is based on the number of devices connected to the network and running. The number of devices is measured by the number of unique MAC addresses connected to the network. In order to purchase Genian NAC in the right size, it is necessary to know the number of devices in operation. This value can usually be found in the following ways:

  • The number recognized by the IT / Network Administrator
  • The existing IT management system (Asset Mgmt, Network Monitoring)
  • Verifying actual numbers through Genian NAC Trial Version (Download and Identify Devices)

All devices that use TCP/IP communication, such as IP phones, surveillance cameras, as well as PCs should be considered as devices.

As your network grows, and the number of devices exceed your License limit, some information of new devices will be hide. But all policies work normally. (Product feature limitations due to license overrun may change without notice.)


When devices are no longer seen on the network the License will then be carried over to the next active and running device. If you purchase an on-premise product, there are no licensing deadlines, only maintenance expirations. If maintenance contract expires, then you cannot upgrade to a newer version or update any of the various databases.

Step 2. Identify the Total Active Nodes Number for Hardware

You need to know the number of nodes to estimate the capacity of the policy server. A node is an endpoint on the network consisting of a combination of IP and MAC. If a system with a single MAC address is using multiple IPs at the same time, the number of devices is one, but the number of nodes can be several. Because Genian NAC manages all information on a per-node basis, it is closely related to the number of nodes in the capacity of the policy server.

Depending on the number of nodes in the network you wish to install, we recommend the following minimum specifications for policy server:

  2,000 Nodes 10,000 Nodes 20,000 Nodes
CPU Intel Dual Core 2Ghz Intel E3 Quad Core 3.4Ghz Intel E5 Quad Core 3.5GHz
Memory 8 GB 16 GB 32 GB
Storage SSD 128 GB SSD 256 GB SSD 512 GB

Step 3. Identify the Total Managed Networks Number

Genian NAC requires the installation of a sensor for every single layer 2 broadcast domain. Therefore, the number of managed broadcast domains is an important factor in determining the sizing of the product. The number of network sensors required depends on two factors:

  • Number of VLANs
  • Number of remote networks with routing

A single network sensor can support up to 128 VLANs. When an 802.1Q VLAN Trunk connection is provided through the Core Switch, sensor services for up to 128 networks are provided over a single physical connection. If the managed network is physically separated and configured as a WAN connection, one Sensor will not be able to configure Layer 2 connections to different regions. If this is the case, you will need to configure a separate sensor for the remote network.

For example, if you have a corporate network with 60 VLANs and two branch offices with 3 VLANs each, you will need a total of three sensors.

Step 4. Identify the Total Agent Applied Devices Number

The number of systems requiring agent installation is closely related to the capacity of the policy server. Data and various events collected by the agent are sent directly to the policy server. Therefore, when the number of agents is large or the agent performs complicated tasks, the load on the policy server becomes high. We recommend that you follow these minimum requirements:

  1,000 Agents 5,000 Agents 10,000 Agents
CPU Intel Dual Core 2Ghz Intel E3 Quad Core 3.4Ghz Intel E5 Quad Core 3.5GHz
Memory 8 GB 16 GB 32 GB
Storage SSD 128 GB SSD 256 GB SSD 512 GB

Genian NAC supports agents for windows and macOS operating systems. The quantity of agents may be less than or equal to the number of systems in which Windows and macOS operating systems are installed.

The Genian NAC Policy Server can be divided into two parts: a node server that receives and processes data from network sensors and agents, and a database that stores data. In a small to medium-sized operating environment, it is common for two functions to work together on a single server, but in a large-scale operating environment, the two functions can be operated as separate servers. If your network consists of more than 10,000 nodes, consider configuring the node server and database separately.

Step 5. Availability and Reliability Requirements

For availability and reliability, Genian NAC supports Active Standby configuration. By configuring Backup system for policy server and network sensor, service can be provided without interruption in case of master system failure. For this, Genian NAC provides its own HA capabilities to automatically detect master system failures.

HA configuration requires an additional backup system for each system, so you need to prepare twice the number of devices required for service configuration.

Sizing Questionnaire

Please answer the following questions:

Number of Devices (Number of unique MACs on network)  
Number of Nodes (Number of MAC+IP conbinations on network)  
Number of L2 Networks (Number of broadcast domains)  
Number of Network Sensors (One sensor supports up to 128 VLANs, each remote network needs a Sensor)  
Number of Agent Applied Devices  
Policy Server Functional Serparation (Node Server/Database Server) YES / NO
High Availability for Policy Server YES / NO
High Availability for Network Sensor YES / NO