I have previously discussed machine state and 4 Way Authentication briefly, here I want to discuss Open System Authentication specifically 802.11 Association. Before an RSNA is established between two devices they have to first go through Open System Authentication. STA must be Associated and Authenticated to the device. As shown in the picture below following…
Category: Wireless
Common Cisco WLC commands
Graphical interfaces are cool and some people prefer them period. I however believe that everything has its use and personally I love to utilize command line anytime I can when it comes to troubleshooting, configuring or looking at information. Yes there are times when I do like to use a GUI but especially when it…
CWAP 403 Study Resources
I recently took my CWAP 403 test and after two months of studying I failed in my first try. I scored 63%, 70% is needed to pass the test. It was a failure however I did learn couple of lessons and one of the most important lesson I learned was, “unless I am 200% certain…
CWAP – Group Key Handshake
Group Key Handshake is a two way handshake that happens when an access point needs to deliver a new GTK to all client stations. GTK is used to encrypt the broadcast and multicast traffic. An important thing to remember here is that this is a separate process as opposed to PTK generation, if it was…
CWAP – 802.11 Frames
So with 802.11 there are different types of frames they they all have sub-types. Knowing these frames and where to find them is helpful when capturing data. It is not fun trying to get them in your head when studying for the test, however in my opinion it is easy when you are actually looking…
CWAP 403 – PHY (PLCP)
802.11 is Layer 2 and Layer 1. After frames come to Layer 1 from PPDU pre 802.11-2016 standard shows there are two interfaces PLCP and PMD as show below. NOTE: Per 802.11-2016 there is no longer PMD and PLCP, please read this article R.I.P. PMD by Robert Haviland explaining it really well. Since my post…
CWAP – Machine State/EAP/4-Way Handshake
This is something that keeps coming up while studying for different certifications and I always have to review everything, flip through the pages since there are technically 3 sections here, I decided to write up a quick overview of all 3 including the flow as shown in the diagram below. When a Wireless Client connects…
Brocade ICX 6450 PoE Configuration
Recently I configured a Brocade ICX6450 PoE switch on the network and all was working well until my customer hooked up a phone to one of the ports I configured. I was told that the phone won’t power on. Now on a Cisco PoE Switch, I’m used to just simply plugging in phones and getting power. With the Brocade…
Cisco 1142 not joining Cisco 2504 WLC
%PKI-3-CERTIFICATE_INVALID_NOT_YET_VALID Recently I was setting up my lab environment with a Cisco 1142 Access Point and a Cisco 2504 Wireless LAN Controller and I ran into a minor issue. Cisco 1142 Access Point was not joining the WLC. I was getting the following error message when I consoled into the access point. *Jan 1 04:35:10.126:…
Aerohive – [wifi]: wl1: PHYTX error
[wifi]: wl1: PHYTX error Aerohive Access point Saw following errors in Aerohive AP230. 5 GHz radio won’t serve clients. Reboot or changing channels which resets the wifi1 interfaces fixes the issue temporarily. Looks like the issue may have been resolved in 8.2r5. Will update. 2019-03-22 09:26:29 info kernel: [wifi]: wl1: PHYTX error 2019-03-22 09:26:29 info…