FYI, I'm working with our support for the OSL on this.  We are banning the
users and we are also going to set emails from new users to be moderated.
 I think that's our best course of action at the moment, although new users
will have some delay getting their messages out.


Jeff Rensink - CCIE #24834 (Wireless, R&S)
Senior Technical Instructor - IPexpert


On Fri, Sep 13, 2013 at 5:46 AM, tabitha soans <[email protected]> wrote:

> We are really chatting great let us know if you also want to join and
> learn something from it.!
>
> Anyone interested to work together i have scheduled my attempt and want to
> discuss rea lab we can do it add me on skype
>
> thanks
>
>
> On Fri, Sep 13, 2013 at 1:37 AM, Jason Boyers <[email protected]> wrote:
>
>> Can someone block this guy?  Not for hijacking a question (which is
>> rude), but the idea of "rea l lab questions" smells of "actual lab
>> questions" which is illegal and can be cause for removal of your Cisco
>> certifications and blocking from obtaining the CCIE.
>>
>> Jason Boyers, CCIE #26024 (Wireless)
>> Blog: netboyers.wordpress.com
>>
>>
>> On Thu, Sep 12, 2013 at 3:47 PM, john arther <[email protected]>wrote:
>>
>>> Hi,
>>>
>>> If anyone want to pass CCIE WIRELESS LAB then lets discuss on rea l lab
>>> questions and work on it lets break the lab share the questions and
>>> solutions
>>>
>>> Add me on skype id is (*quad.quad4*)
>>>
>>> Thanks
>>>
>>>
>>> On Thu, Sep 12, 2013 at 7:17 PM, Jeen Sern Chew <[email protected]>wrote:
>>>
>>>> Thanks Jason and Jeff,
>>>>
>>>> It is really confusing, especially with conflicting information out
>>>> there, like with the hysteresis of being 3 dBm both ways or 3 dBm one and
>>>> 6dBm the other.
>>>>
>>>> Also after calculating, how would you know to increase or decrease the
>>>> power?
>>>>
>>>> The following is how I understand it after some thinking. Some of the
>>>> figures are just base on real world experience. Say you do a voice survey
>>>> and place your APs to provide coverage of -67 dBm, 20% overlap and power
>>>> level of 6-25 mW. The following are the assumptions:
>>>> - Cisco formula as mentioned above is correct
>>>> - TPC only decreases power
>>>> - Hysteresis of 3 dBm
>>>> - There's another APs see each other rather than by transmitting
>>>> neighbour message at full power
>>>>
>>>> Starts off at level 1 / 100mW. I chose the 3rd highest RSSI to be -50
>>>> dBm as that would happen in a voice/high density survey.
>>>>
>>>> 20 - (-67 - (-50)) = 20 - (-17) = 37           Hysteresis met, decrease
>>>> from level 1 / 20dB to level 2 / 17dB
>>>> 20 - (-67 - (-60)) = 20 - (-7) =  27            Hysteresis met,
>>>> decrease from level 2 / 17dB to level 3 / 14dB
>>>> 20 - (-67 - (-70)) = 20 - 3 =  17               Hysteresis met,
>>>> decrease from level 3 / 14dB to level 4 / 11dB
>>>> 20 - (-67 - (-80)) = 20 - 13 =  7               Hysteresis met,
>>>> decrease from level 4 / 11dB to level 5 / 9dB
>>>> 20 - (-67 - (-85)) = 20 - 18 =  2               Hysteresis not met.
>>>> Stay at level 5 / 9dB
>>>>
>>>> At level 5, it is close to the figures of some deployments out there.
>>>>
>>>> Does this calculation make sense? Did I miss anything? If it correct,
>>>> great! Just need to confirm the assumptions above then.
>>>>
>>>> Thanks
>>>> J Chew
>>>>
>>>>
>>>> On 12 September 2013 01:39, Jeff Rensink <[email protected]> wrote:
>>>>
>>>>> This is a frustrating topic indeed.
>>>>>
>>>>> TPC will do both power decreases and increases as the environment
>>>>> changes.  But the formula that the document references has a flaw that I
>>>>> haven't totally reconciled.
>>>>>
>>>>> Tx_Max for given AP + (Tx power control thresh – RSSI of 3rd highest
>>>>> neighbor above the threshold)
>>>>>
>>>>> Tx_Max for a given AP should be a static value, correct?  It's
>>>>> supposedly the max possible power that the radio can transmit at for its
>>>>> chosen channel.  The Tx power control threshold is also a static value 
>>>>> that
>>>>> is configurable.  So the assumption is that the RSSI of the 3rd loudest
>>>>> neighbor changes along with the current AP power level.
>>>>>
>>>>> If I understand things correctly, the RSSI of the 3rd loudest neighbor
>>>>> is determined by AP neighbor messages.  According to documentation (and I
>>>>> believe I've tested this myself), neighbor messages are always sent out at
>>>>> the highest power level and lowest data rate.  If that is indeed true, 
>>>>> then
>>>>> the RSSI of the third loudest neighbor is yet another static value
>>>>> (assuming the environment isn't changing).
>>>>>
>>>>> So if none of the variables in the equation are actually variable, the
>>>>> results of the equation are always the same.  That would mean either the
>>>>> power level would always settle into the max power or the minimum power.
>>>>>  That's not true, so something seems off in the equation or the 
>>>>> description
>>>>> of the variables in the equation.
>>>>>
>>>>> My guess is the formula is closer to (Max_AP_Power - Current_AP_Power)
>>>>> - (3rd_loudest_neighbor - TPC_Threshold)
>>>>>
>>>>> A positive result would result in a power increase.  A negative result
>>>>> would result in a power decrease based on the 3 dBm hysteresis.  According
>>>>> to Jerome Henry, it's 3 dBm in both directions in the 7.0.116.0 code.  
>>>>> This
>>>>> assumes that the 3rd loudest neighbor measurement is pretty much always 
>>>>> the
>>>>> same since neighbor messages are always sent as max power.
>>>>>
>>>>> So let's say we start at full power on the 2.4 GHz band with a 3rd
>>>>> loudest neighbor of -60 and threshold of -67.
>>>>>
>>>>> (20-20)-(-60-(-67)) = 0-7 = -7
>>>>>
>>>>> -7 is lower than -3, so we drop the power down a level
>>>>>
>>>>> (20-17)-(-60-(-67)) = 3 - 7 = -4
>>>>>
>>>>> -4 is lower than -3, so we drop the power once more.
>>>>>
>>>>> (20-14)-(-60-(-67)) = 6 - 7 = -1
>>>>>
>>>>> -1 is not lower than -3, so it doesn't change.
>>>>>
>>>>> This is a total guess, but it makes more sense to me than the formula
>>>>> in the documentation.  But in the real world, the higher the TPC 
>>>>> threshold,
>>>>> the higher the power levels will be.  For instance, a threshold of -60
>>>>> would result in higher power levels than a threshold of -70.  So if you 
>>>>> are
>>>>> seeing your APs in a particular location settle in at too high or too low
>>>>> of power levels on average, tweak the threshold as needed.  Every 
>>>>> increment
>>>>> of 3 should result in powers going up/down one level on average.
>>>>>
>>>>> Jeff Rensink - CCIE #24834 (Wireless, R&S)
>>>>> Senior Technical Instructor - IPexpert
>>>>>
>>>>>
>>>>> On Wed, Sep 11, 2013 at 9:14 AM, Jason Boyers <[email protected]>wrote:
>>>>>
>>>>>> This is a confusing algorithm.  Basically, think of it this way:
>>>>>>
>>>>>> 1) Three neighbors (at least) hear an APs radio at or stronger than
>>>>>> the TPC Tx mac value configured under the WLC TPC settings for that PHY
>>>>>> (802.11a/n or 802.11/b/g/n)
>>>>>> 2) If #1 is true, then that formula provided is used.
>>>>>> - The "Tx_Max for given AP" is the maximum transmit power for that
>>>>>> channel on that particular radio.  So, for a 2.4GHz radio, that would be
>>>>>> 100mW (20 dBm), since that is the maximum for 802.11b.  5GHz is more
>>>>>> confusing, as it various based on channel and model of AP.
>>>>>> - The "Tx power control thresh" is the value that is entered in the
>>>>>> WLC
>>>>>> - Note that there is an "hysteresis" value of 3dB for decreasing and
>>>>>> 6dB (or it was at one point - someone correct me for the current values)
>>>>>> for increasing the power levels.  In other words, the value that is given
>>>>>> at the end of the formula has to be at least that dB difference from the
>>>>>> current value in order for a change to occur.
>>>>>> 3) The AP's radio that is heard by the other three APs is the one
>>>>>> that is decreased (or it can be increased) if the hysteresis value is
>>>>>> exceeded.
>>>>>> 4) When the formula is run again, it is presumed that the three
>>>>>> neighbors that are hearing the APs signal are hearing a weaker signal.
>>>>>> 5) Keep in mind that the algorithm is always from the perspective of
>>>>>> an AP being heard by 3 or more neighbors, not an AP hearing 3 or more
>>>>>> neighbors.
>>>>>>
>>>>>> Hope this helps.
>>>>>>
>>>>>> Jason Boyers, CCIE #26024 (Wireless)
>>>>>> Blog: netboyers.wordpress.com
>>>>>>
>>>>>>
>>>>>> On Wed, Sep 11, 2013 at 9:36 AM, Jeen Sern Chew 
>>>>>> <[email protected]>wrote:
>>>>>>
>>>>>>> Hey guys,
>>>>>>>
>>>>>>> I have a TPC question.
>>>>>>>
>>>>>>> There are many conflicting information from different Cisco docs.
>>>>>>> Some say TPC increase and decrease power, some say TPC only decreases 
>>>>>>> power
>>>>>>> while CHD increases power. Does TPC do both or only increase?
>>>>>>>
>>>>>>> Also Cisco gives the TPC formula of:
>>>>>>> Tx_Max for given AP + (Tx power control thresh – RSSI of 3rd highest
>>>>>>> neighbor above the threshold).
>>>>>>>
>>>>>>> Is the Tx_Max is the Tx_Max of the specific AP? or Is it the Tx_Max
>>>>>>> configured on under TPC in WLC?
>>>>>>>
>>>>>>> Also, when the calculation is done, I am assuming the power
>>>>>>> increase/decrease occurs on the neighbour with the third highest RSSI?
>>>>>>>
>>>>>>> Thanks
>>>>>>>
>>>>>>> Regards,
>>>>>>> J Chew
>>>>>>>
>>>>>>> _______________________________________________
>>>>>>> For more information regarding industry leading CCIE Lab training,
>>>>>>> please visit www.ipexpert.com
>>>>>>>
>>>>>>> Are you a CCNP or CCIE and looking for a job? Check out
>>>>>>> www.PlatinumPlacement.com
>>>>>>>
>>>>>>>
>>>>>>
>>>>>> _______________________________________________
>>>>>> For more information regarding industry leading CCIE Lab training,
>>>>>> please visit www.ipexpert.com
>>>>>>
>>>>>> Are you a CCNP or CCIE and looking for a job? Check out
>>>>>> www.PlatinumPlacement.com
>>>>>>
>>>>>>
>>>>>
>>>>
>>>> _______________________________________________
>>>> For more information regarding industry leading CCIE Lab training,
>>>> please visit www.ipexpert.com
>>>>
>>>> Are you a CCNP or CCIE and looking for a job? Check out
>>>> www.PlatinumPlacement.com
>>>>
>>>>
>>>
>>> _______________________________________________
>>> For more information regarding industry leading CCIE Lab training,
>>> please visit www.ipexpert.com
>>>
>>> Are you a CCNP or CCIE and looking for a job? Check out
>>> www.PlatinumPlacement.com
>>>
>>>
>>
>> _______________________________________________
>> For more information regarding industry leading CCIE Lab training, please
>> visit www.ipexpert.com
>>
>> Are you a CCNP or CCIE and looking for a job? Check out
>> www.PlatinumPlacement.com
>>
>>
>
> _______________________________________________
> For more information regarding industry leading CCIE Lab training, please
> visit www.ipexpert.com
>
> Are you a CCNP or CCIE and looking for a job? Check out
> www.PlatinumPlacement.com
>
>
_______________________________________________
For more information regarding industry leading CCIE Lab training, please visit 
www.ipexpert.com

Are you a CCNP or CCIE and looking for a job? Check out 
www.PlatinumPlacement.com

Reply via email to