latency betw WLC & AP (100ms or 300ms?)

[yjooteck]

Hi,

[From H-REAP deployment guide]

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Roundtrip latency must not exceed 300 milliseconds (ms) between the access point and the controller,

and LWAPP or CAPWAP control packets must be prioritized over all other traffic.

[From Enterprise Mobility 4.1]

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Latency-A given WAN link should not impose latencies greater than 100 ms. The AP sends heartbeat messages to the WLC once every thirty seconds. If a heartbeat response is missed, the AP sends five successive heartbeats (one per second) to determine whether connectivity still exists. If connectivity is lost, the H-REAP AP switches to standalone mode. The AP itself is relatively delay tolerant. However, at the client, timers associated with authentication are sensitive to link delay, and thus a constraint of < 100 ms is required. Otherwise, the client can timeout waiting to authenticate, which can cause other unpredictable behaviors, such as looping.

So which is correct? one Cisco AS engineer told me that with WLC6.0, delay can be 300ms. WLC prior to 6.0 is 100ms. But i can't find any documentation on this.

Any comments greatly appreciated.

Thanks

Eng Wee

[weterry]

Don't qoute me on this, but I think in 5.x is where the 100ms latency was increased to 300ms.

The 4.1 deployment guide is accurate, for 4.1. It should not be greater than 100ms. The HREAP Deployment Guide that I found, is written for 5.1, and it mentions 300ms.