Before I came to work for Aerohive, I ran my own Wi-Fi consulting and training company for 10 years. Over the years I worked with WLAN products from pretty much all the WLAN vendors and acquired a lot of WLAN 
hardware for testing purposes in my lab.
As a matter of fact, I procured so much hardware, that I literally had to buy a bigger home 11 years ago because my former house was overrun with WLAN gear. And now I no longer have any room in my current home and I keep tripping over 802.11b access points. So, I have begun the task of cleansing my home of Wi-Fi that will never die. I am trying to donate most of the equipment to charity.
As I have been boxing up the WLAN toys of yesteryear, a lot of wireless memories have been popping up in my brain. I decided to take pictures of the equipment and share them via Twitter tagged with #wifinostalgia. The response to the tweets was so much fun, that I decided to write a series of blogs about Wi-Fi dinosaurs that are now mostly extinct.
Back to the beginning
Let’s start with frequency hopping spread spectrum (FHSS)WLAN radios.
When the original 802.11 standard was ratified in the 1997, three Physical layer specifications were defined. WLAN vendors could manufacture WLAN equipment using either frequency hopping spread spectrum (FHSS), direct sequence spread spectrum (DSSS) or infrared (IR).
As far as I know there never was an 802.11 infrared access point, but WLAN vendors did manufacture both FHSS and DSSS radios. Because these spread spectrum technologies differed, the radios could not communicate with each other and often had a hard time coexisting. The majority of legacy WLAN deployments used frequency hopping, but some DSSS solutions were available as well. 802.11 FHSS access points were primarily deployed in warehouses and used together with wireless handheld devices for data collection and inventory control.
FHSS radios do not transmit on a fixed channel but instead transmit on multiple small channels in a sequence-hopping pattern as shown below. Although the technology is not conducive for bandwidth, FHSS is very resilient against RF interference. Actress Hedy Lamarr and composer George Antheil originally patented FHSS technology in 1942 during World War II.
Some of the first WLAN equipment I ever touched used FHSS. A little company based out of Akron, Ohio called Aironet manufactured both FHSS and DSSS APs and client radios that transmitted in the 2.4 GHz band.
The image below depicts some legacy Aironet FHSS equipment. In later years, Cisco would purchase Aironet and begin to offer a line of autonomous APs and WLAN PCMCIA client radios.
The FHSS radios had data rates of 1 or 2 Mbps. Look at the image below and notice the 10Base2, 10Base5 and 10BaseT wired interfaces on the Aironet access point.
Yes, there was a day when APs could be connected to the wired network via thinet, thicknet or very slow Ethernet.
Several other companies such as Proxim and Intermec also manufactured FHSS equipment. The image below displays a couple of Proxim RangeLAN2 FHSS access points.
Future 802.11 amendments such as 802.11b and 802.11a would abandon frequency hopping for physical layer technologies that could support higher data rates.
However, back in the day, FHSS was the cool WLAN technology sporadically deployed in the enterprise. Frequency hopping never really caught on within the SoHo market, but does anyone remember HomeRF? SoHo vendors such as Linksys and Belkin offered 802.11b WLAN routers that used DSSS technology.
However, vendors such as Proxim, Intel and Motorola offered a competing wireless technology that utilized frequency hopping. The competing technology was called Shared Wireless Access Protocol (SWAP) or more commonly known as HomeRF. As shown below, these home units used FHSS and had data rates of up to 10 Mbps. Also, HomeRF never caught on and 802.11 wireless won the battle for the home WLAN market.
I hope you have enjoyed this little stroll down Wi-Fi memory lane. As I continue to box up all the old gear in my house, I will share more Wi-Fi memories in future blogs.
In the meantime, if you have any stories or pictures about Wi-Fi equipment that has been retired and put out to pasture, tweet @mistermultipath and and hashtag #wifiNostalgia .
Stay tuned for more installments of this blog series.