Size of the wireless network

[Philip Vilhelmsson]

Hi,

Lets say we have a company that does regular usage, surfing the web, email,occasional large file transfer, working in internal systems. Using one SSID, one VLAN, one DHCP-scope. When will you start to see bad performance regarding number of clients connected at the same time? 500, 1k, 2k clients?

When will clients broadcast trafic, like ARP, become a problem for the wireless network?

Regards

Philip

[vlad.mihailov]

The quiestion is very loaded IMHO. Split it in two different parts and this will help you answer it:

1. How many users connected wirelessly

2. How many nodes on the VLAN that will begin affecting its performance.

1. as for wireless the main concern is amount of clients per Access Point and the amount of Clients/Access Points per Controller. One Access Point can safely handly 10-20 clients (depending on their cell size, minimum allowed data rate, average data rate and proper RF design (no co-channel, minimized hidden nodes etc).

Then remember that with Cisco all the clients traffic terminate at the controller, so having an X amount of 3600-series APs with 150-300mbps capable APs there will be a need for a backbone of that controller to handle say 20-25% aggregated traffic (and may be more depending on user traffic).

2. Is not just a wireless question as Wireless clients will be confined to their cells. I'd suggest avoind building subnets with larger than 1022 hosts (/22 bit subnet mask) and if possible using smaller subnets (/23 bit).

[c.flavell]

Hi Vlad

If they are on the same vlan you can use automonous access points up to 62 all connected into individual Gigabit ports on the switch so you remove the WLC bottle neck. Roaming is supported using WDS and if the WDS master fails then next access points takes over. No single point of failure, no bottle neck and no need to buy a controller.

Regards Conwyn

[vlad.mihailov]

Agreed on the simple way to manage bottlenecks although I am likely sold on the controller-based systems: configuration, updates, management, RF management etc etc becomes so much easier when done through WLC.