Ilya,
Theres a misconception here. You're comparing a MONITORING system with a MANAGEMENT system.
Cacti can graph a lot of information about your network. That's not the main purpose of Extreme Management Center.
Extreme Management Center (EMC) will:
- Discover your devices. Any device that can respond to SNMP or PING can be discovered. If they are Extreme switches, ZTP+ will allow them to be discovered and configured automatically as they are connected to the network. it can also periodically scan your sites looking for new devices not supporting ZTP+
- Inventory your devices. EMC will collect serial numbers, modules, software versions, empty port information, etc., so you can create reports on this information and know what you have without needing to go check physically the device.
- Manage firmware. You can check the firmware versions of your devices and schedule when to update and reboot them, a single device at a time or in groups.
- Manage configurations. You can archive the configurations of your devices and restore them, if needed. If the configuration of a device has changed, you can look at the current configuration and compare it to a previous one to see what has changed. The additions, deletions and changes will be highlighted in different colors to help you identify the changes. You can even set up an alarm that alerts you that the configuration of an important device (e.g. core switch) has changed, so you can immediatelly take action.
- Centralize Events and Alarms. All events and alarms from the discovered devices will be presented in a single screen. You can create your own alarms based on certain events (e.g. if the archived configuration of a device changes, or if the port of an important server goes down).
- Map devices. Using various link discovey protocols (LLDP, EDP, CDP...) EMC will create topological maps of your network. In these maps you will be able to see the VLANs, EAPS rings and MLAG links configured in each Extreme device. You will also be able to create vlans or add ports to the existing ones.
- Integrate third-party devices. Non-Extreme devices supporting SNMP can be integrated and managed through EMC. Using FlexViews you can retrieve SNMP information and display it in table, bar graph, line graph or pie chart. You can even edit writable information and apply it back to the device.
- Manage Policy.You can create policies and group them in roles for Extreme switches and AP's in a centralized way. These policies and roles can then applied to switches and AP's to be used together with Extreme Access Control. If you decide to change a role in some way, you do it in EMC, enforce the change in all the switches and AP's and the change is INSTANTLY applied to all devices and clients using that role.
- Integrate your wireless network. EMC will let you see which ExtremeWireless AP's are active and which are down, the channels used by each AP, the clients connected to each AP, the band, technology and SSIDs used, SNR and other connection information.
- integrate Extreme Access Control. EAC can apply the Roles and Policies created and managed by EMC to users based on identity, credentials, location, device used, time of day, etc. EMC will display the information obtained from EAC (user, device, Role applied, location, etc...)
- Integrate Extreme Application Analytics. EAA can detect the applications present in your network. EMC will show the information collected by EAA. If EAC is present, EMC will even show you the name of the users using a certain application.
- Report. EMC will let you create reports on all the information described in the previous points. It will even let you create your own reports.
Most of these things can be applied not only to Extreme devices but to third party devices also.
As you can see, there's a lot of things that EMC can do that Cacti will not. They are not mutually exclusive, but complementary solutions.
You will need the Advanced version of EMC if you want to have support for EAA, wireless heat maps and wireless client locationing. Otherwise, the normal version will be enough. The base version is limited and does not include all the functionality described.
There are several heat maps available. When you select Wireless Coverage and enable Show Coverage, you can use Mode to select between the following heat maps:
- Signal Strength: Shows the signal strenght in different parts of the foor plant.
- Channel Coverage: Shows the channes used by the different AP's.
- Data Rate: Shows the maximum expected data rate in different parts of the floor plant
- Location Readiness: Shows if the AP coverage will allow for detailed or coarse locationing of clients.
Regarding the heat maps, these are extrapolations of the information received from the AP's. You will need to load the floor plan into EMC and mark the construction details (walls, windows, doors, etc.) so EMC can calculate the attenuation in the path of the signal. These floorplans are usually created in Ekahau when making a Predictive Survey. EMC lets you import the maps already created with Ekahau to reduce the work required.
Regarding the number of devices, if you have 30+ Extreme switches, 50+ third party devices and one wireless controller, you would need the 100-device normal version (NMS-100), which supports up to 1,000 AP's (these are not added individually, only the controller is added and all the AP and wireless client information is gathered though it)