First look: Cisco 802.11ac module for the AP3600

Last year Cisco launched their 3rd modular Access Point, the 3602 featuring 3 Spatial Stream 802.11n, dual radios, and CleanAir support. One of the much touted features was the introduction of a ‘future-use’ modular slot across the back of the Access Point (now called Adaptive Radio Modules ). This was to future proof your investment and at the time, Cisco took a lot of heat for this modular future proof approach to investment protection. Sometime after the Access Point was launched, Cisco announced that there would be at least two modules available, one being the WSSI module (for full time monitoring of off channel events) and the 802.11ac module (to support the yet-to-be ratified 802.11ac standard). I’ve gotten my hands on an 802.11ac module and here is what I know:

a) It’s easy to install:

With two thumb screws on the module itself, you simply grab the AP off of the ceiling tile, unplug the ethernet cable, flip it over, remove a piece of tape to expose the connector, place the module on the back, screw down the thumb screws, re-attach the network cable, and rehang the AP.

802.11ac module

802.11ac module

802.11ac module installed

802.11ac module installed

b) It can require up to 20 Watts*:

#show power inline gigabitEthernet 0/2
Interface Admin  Oper       Power   Device              Class Max
--------- ------ ---------- ------- ------------------- ----- ----
Gi0/2     auto   on         20.0    AIR-CAP3602I-A-K9   4     30.0 

Interface  AdminPowerMax   AdminConsumption    
             (Watts)           (Watts)           
---------- --------------- --------------------  

Gi0/2                 30.0                 30.0
#show power inline gigabitEthernet 0/2 detail 
 Interface: Gi0/2
 Inline Power Mode: auto
 Operational status: on
 Device Detected: no
 Device Type: cisco AIR-CAP3602I-
 IEEE Class: 4
 Discovery mechanism used/configured: Unknown
 Police: off

 Power Allocated 
 Admin Value: 30.0
 Power drawn from the source: 20.0
 Power available to the device: 20.0

 Actual consumption
 Measured at the port: 8.6
 Maximum Power drawn by the device since powered on: 10.2

 Absent Counter: 0
 Over Current Counter: 0
 Short Current Counter: 0
 Invalid Signature Counter: 0
 Power Denied Counter: 0

 Power Negotiation Used: CDP
 LLDP Power Negotiation --Sent to PD--      --Rcvd from PD--
   Power Type:          -                    -
   Power Source:        -                    -
   Power Priority:      -                    -
   Requested Power(W):  -                    -
   Allocated Power(W):  -                    -

c) It ‘just works’:

The 802.11ac module shows up as you’d expect – as a ‘slot 2 radio’ and you can Admin Enable and Disable it. Aside from that, it takes all of it’s RF specific configuration from it’s parent radio – operating in tandem with the integrated 5GHz radio that services your 5GHz 802.11n clients. As with all hardware updates, you’ll need to update your WLC code to a version that supports the module but this is only mentioned as a ‘well duh’ requirement. 🙂

Since the module is adding a radio specifically to support 802.11ac clients, it increases the total client capacity of the AP3600 to a whopping 450 (200 for 802.11n 2.4GHz, 200 for 802.11n 5GHz, and 50 for 802.11ac)! While the jury is out about it being a good idea to try and support 450 clients on a single AP, the capacity numbers are listed for the inevitable vendor-bashing that is sure to ensue!

d) Clients will be the next big challenge:

As with the transition from 802.11b to 802.11g, then to 802.11n, the transition to 802.11ac will derive most of it’s pain from client adapters. Driver updates, marginal modulation benefits at distance, etc. The biggest benefit from 802.11ac will be the cleaner frequency requirement (5GHz) but poor roaming choices from clients will most certainly be the biggest pain point we all grapple with.




*Does the module require more than 15.4W PoE?

No! The module can be operated at *full* 802.11ac performance in class 3 power by disabling the 2.4GHz radio on the AP. This is the only solution on the market that offers *full* 802.11ac performance in Class 3 power. This means that you can deploy 802.11ac today even without switch upgrades! Here is a show power from a AP and module servicing 802.11ac clients:

#show power inline gi0/2
Interface Admin  Oper       Power   Device              Class Max
--------- ------ ---------- ------- ------------------- ----- ----
Gi0/2     static on         15.4    AIR-CAP3602I-A-K9   4     15.4 

Interface  AdminPowerMax   AdminConsumption    
             (Watts)           (Watts)           
---------- --------------- --------------------  

Gi0/2                 15.4                 15.4

Is this Cisco’s 802.11ac Access Point?

No! This is a 3 spatial stream 802.11n Access Point with an 802.11ac module. While I cannot comment on future or unannounced products, it stands to reason that Cisco will continue to evolve products and announce those products when they’re ready. It’s my opinion that a fully fledged 802.11ac Access Point will be announced at some point.

Can you tell me more about a dedicated 802.11ac Access Point from Cisco?

No. I have no disclosable information on an 802.11ac Access Point from Cisco.

How much does the module cost?

The list price for the module is around $500. Engage your Cisco Account Manager and Partner team for your discounted pricing (and don’t pay list). 🙂

What other modules are there for the AP3600?

There is a small cell 3G module available.

Will there be future modular Access Points from Cisco that support these modules?

I have no disclosable information on an unannounced products from Cisco.

Is this the end? What about speeds and feeds? What about a take apart so we can see what’s inside?

There will be a followup post. What would you like to see?

5 Responses to First look: Cisco 802.11ac module for the AP3600

  1. Hi Sam,
    First, good post! Thanks for the update on this module. I like how easy it is to install the module, but when I consider the cost of the base AP, the module (which isn’t cheap even after a generous discount, especially when applied across multiple APs in an enterprise environment), and the cost of an installation technician to install the modules, I can’t see this being feasible for most customers except in situations where the installation expense is removed and organizations have their own network admins on salary work overtime to install them, or in limited use in specific high-density areas. Why not save your money for a dedicated 802.11ac AP that has newer hardware components throughout?

    Also, saying this is a fully capable 802.11ac AP on 802.3af power budget is a stretch. Disabling the 2.4 GHz radio is big caveat and ultimately its still loss of features. So, I don’t buy that point at all.

    I also am curious about the throughput performance once you get to testing that. I keep hearing from hardware engineers that 802.11ac has bigger CPU requirements to push the advertised throughput and with the older 3600 hardware platform I’d like to see what throughput it can actually push. I’m no expert in this area and will rely on testing such as yours as to what the actual performance will be. So, consider this a request for performance testing 🙂

    Another question I have for you: can you confirm that the 11ac module and the 11n 5 GHz radio work in tandem and time-slice for airtime and transmissions? I believe this to be the case, but I’m wondering if you can confirm. For instance, it’s not a 3rd radio operating on a completely different 5 GHz channel than the 11n 5 GHz radio, which would also require hardware shielding to mitigate adjacent-channel interference (ACI) when in such close physical proximity to each other. Therefore, I think it’s essentially an upgrade to the 5GHz radio to support 11ac clients, not a “net new” 3rd radio. This has implications for network capacity and high-density client handling, so it would be nice to get clarification.

    Thanks for your research on this and posting your findings!

    Andrew von Nagy

    • scwifi says:

      Yes, I realize the Class 3 power is a stretch, but some other vendors are requiring you to cripple 802.11ac in some fashion to run at 15.4 Watts. You’re correct that this will be potentially relevant to High Density deployments where it’s commonplace to disable 2.4GHz radios anyway. Regarding your radio questions, the module does indeed work in tandem with the integrated radio. Infact, it’s channel config comes from the base 5GHz radio. Put another way, if you disable the integrated Slot 1 5GHz 802.11n radio with the module installed, it also disables the 802.11ac radio. The module is strictly for supporting .11ac clients and the existing radio continues to handle the .11n 5GHz clients. Speeds and feeds will be coming when my client adapters settle down some (or I get ahold of one of those shiny new Macs 🙂 )

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