It seems that everyone I talk to has wireless challenges in their environment and network. I recently deployed ~ 60 Cisco 3702e Access Points paired with a set of Cisco 5508 Wireless LAN Controllers running software release 7.6.100 in a newly renovated building. I wasn’t anticipating any issues or problems but you can guess what I ended up stumbling upon. While we thought everything was working fine we quickly discovered that 5Ghz clients were having severe performance and connectivity issues. I could run continuous ICMP pings but the moment I put the client under load I would either loose connectivity or experience severe packet loss upwards of 80-90%. We had the same results from a Lenovo T420 and T430 laptop and a MacBook Air.
We opened a case with Cisco TAC and discovered that we were experiencing a known issue;
- CSCuj17283 – Cisco AP3700 used 8 replay counters with clients that support only one (ARP failed).
The bug above is resolved in software release 7.6.110, here are the release notes. We’re currently testing software release 7.6.110 although Cisco has just released 7.6.120 – release notes.
If your going to be deploying the Cisco 3700 Access Points you’ll want to make sure that your WLC is running a minimum software release of 7.6.110.
Jason Johnson says
this seems to be pretty common, we had an issue when the 2602 was released with our 5508’s and it was solved by upgrading firmware on the WLC.
Also if you are in a mixed ap environment, always be careful before you upgrade WLC firmware as one upgrade we did dropped 6-7 older access points from the supported list.
Michael McNamara says
Thanks for the comment Jason.
It’s always important to review the release notes and validate the supported AP list.
I am wondering with the introduction of 802.11ac if people will start to swing to using the 5GHz band much more heavily and maybe take some of the load off the swamped 2.4HGz band. In that case I know a couple places that are might have issues because they built their deployments around 2.4GHz which go through walls and floors easier than 5GHz (802.11a). Anyone been able to test how 802.11ac works through walls compared to 802.11a?
Michael McNamara says
In the majority of my deployments I’ve leveraged the 5Ghz and 2.4Ghz bands for different SSIDs/WLANs. I’ve used the 5Ghz band for high-speed corporate devices and the 2.4Ghz band for low-speed devices and public/guest wireless.
You’ll definitely see people start to adopt the 5Ghz band as 802.11ac and 802.11n grow in adoption.