wireless qos training

7/27/2019 Wireless QoS Training

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2006 Cisco Systems, Inc. All rights reserved. Cisco ConfidentialPresentation_ID 1

Cisco UnifiedWireless Network

WLAN QoS

Syed Ali (sali)Network Consulting Engineer


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WLAN QoS

Overall Concept


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CUWN WLAN QoS Goals

Primary Goal

Judicious usage of RF bandwidth. RF bandwidth andresponsiveness is finite and needs to be applied wisely to

serve business needs.

Secondary Goal

Manage LWAPP/CAPWAP tunnel traffic consistently with end-to-end QoS model in balance with wired QoS policies.


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QoS on the WLAN

Shared access to bandwidth

Packets marked with 802.1p and/or DSCP

QoS is currently available to downstream traffic from the AP, but

few devices (WMM) can provide upstream QoS toward the AP Can provide only limited admission control

Unlike wired networks with dedicated bandwidth, WLAN networksmust consider traffic direction when they implement QoS. Traffic isconsidered either upstream or downstream from the point of view

of the AP


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CUWN WLAN QoS translation points

UPSTREAM

Radio upstream QoS:Traffic leaving the WLAN clients and traveling tothe AP. WMM provides upstream QoS for WLANclients supporting WMM (UP marking). Clientupstream QoS depends on client implementation.

Network upstreamTraffic leaving the AP, traveling to the WLC.Tunnel encapsulation. AP classifies traffic from theAP to the upstream network according to the trafficclassification rules of the AP.

WLC tunnel decapsulation andtransmission to wired network

DOWNSTREAM

Wired Network to WLC

Radio downstream QoS:Traffic leaving the AP and traveling to the

WLAN clients. AP tunnel de-capsulation andtransmission/scheduling to WLAN client (WMMclient UP marking).

Network downstream:Traffic leaving the WLC traveling to the AP.Tunnel encapsulation. QoS can be applied atthis point to prioritize and rate-limit traffic to AP.


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Wi-Fi Multimedia(WMM)

WLAN Quality of Service


7/84 2006 Cisco Systems, Inc. All rights reserved. Cisco ConfidentialPresentation_ID 7

802.11 MAC Modes

Coordination functions control access to the wirelessmedium. Two types of services provided are:

Contention based service - provided by DCF

(Distributed Coordination Function)Basis of CSMA/CA, uses random backoff, RTS/CTS

Contention free service - provided by PCF (PointCoordination Function)

Used only in infrastructure networks

Point coordinators residing in access points used

Allows stations to transmit frames after a shorter interval togain priority over contention based services



Distributed Coordination Function (DCF)

DCF used in 802.11 networks to manage access to the RF medium

Data frames in 802.11 are sent using DCF (two main components):

Interframe spaces (SIFS, PIFS, and DIFS)

Random backoff (contention window)



DCF CSMA/CA Algorithm


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DCF, CWmin, CWmax

DCF uses a contention window (CW) binary exponential backoff tocontrol the size of the random backoff defined by the parameters:

aCWmin

aCWmax

Retries (TTL)



Why QOS or 802.11e?

Basic DCF is not QoS friendly

Need to contend for every MSDU

Contention treats all traffic similar.

That is a voice frame contends with the data frame using thesame parameters

No concept of priority to important traffic even insidethe STA.

Once the sequence number is allotted, that MSDU must betransmitted before attempting the next MSDU



Wi-Fi Multimedia

Wi-Fi Multimedia (WMM) is a Wi-Fi Alliance certification of supportfor a set of features in IEEE 802.11e

802.11e introduces additional MAC modes, e.g. the EnhancedDistributed Channel Access (EDCA)

WMM is the implementation of the EDCA component of 802.11e.

Different interframe spacing and CWmin and CwMax values areapplied per traffic classification


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EDCF: CWmin and CWmax

CWmin and CWmax a manipulated to give different QoS

DIFS Contention Window

Slot time

Busy Medium Backoff Window

Defer Access Decrement backoff as long as the

medium is idle

Next Frame(t)

0

CWmin[6]

Voice random backoff range

Video random backoff range

Best effort random backoff range

CWmin[7]

CWmin[0]



EDCF: CWmin and CWmax

CWmin and CWmax a manipulated to give different QoS

This is a statistical process

Station X

Voice 1

Best Effort 1

Voice 2

Best Effort 2

Frame

Defer

Defer

Defer

DIFS DIFS

Frame

DIFS

Backoff time

Backoff time remaining

Defer

Defer

Defer

Frame

Frame

Defer

Defer

Voice 3 Defer Defer Defer

DIFS

Frame

Defer Defer

Defer



WMM Client, eg. VoWLAN Client

VoIP client marks traffic with DSCP Value (EF)

OS Maps DSCP to CoS (6)

WLAN Client Maps CoS to WMM AC (VO)

WMM AC VO gives traffic highest priority



WMM Framing

WMM uses 802.1D priority classification

This is commonly referred to as 802.1p marking

Frame

ControlDur A 1 A 2 A 3

Seq

ControlA 4

QoS

ControlBody FCS

0ack

policyEOSP 0 UP

15-7 6-5 4 3 2-0

802.1D Priority

End of Service Period

0001

Acknowledge

Do not Acknowledge

2 2 6 6 6 2 0 or 6 0 or 2 n 4



WMM Access Categories

Queuing performed on a WMM client or AP

WMM Access Categories are 4 internal queues for the WLAN Radio

Called, bronze, silver, gold, and platinum on the controller

These form a distributed queue for the entire RF channel

Note: These are queues for Unicast frames only, IP Multicast typicallyscheduled in Best Effort queue



WLC QoS Profiles

WLC QoS Profiles match WMM Access Categories



WMM Classification

Uses 802.1p Classification

Priority 802.1 Priority

(User Priority)

802.1p Designation Access

Category

WMM

Designation

Highest 1 BK, Background AC_BK Background

2 -Spare

Lowest 0 BE, Best Effort

3 EE, Excellent Effort AC_BE Best-Effort

4 CL, Control Load

5 VI Video < 100ms AC_VI Video

6 VI Voice < 10ms AC_VO Voice

7 NC, Network Control



IEEE 802.11e WMM Access Categories

Access Category Description 802.1d Tags

WMM Voice Priority

AC_VO

Highest Priority (MultipleCalls, Low Latency and Toll

Voice Quality)7, 6

WMM Video Priority

AC_VIVideo 5, 4

WMM Best EffortPriority

AC_BE

Legacy Devices orApplications That Lack QoS

Capabilities0, 3

WMM BackgroundPriority

AC_BK

Low Priority Traffic (FileTransfers, Printing)

2, 1



Packet Markings

Implementation



WMM, DSCP and 802.1p Relationship


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Mapping of QoS Packet Markings


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The Translation Table

Cisco AVVID 802.1p

UP-Based Traffic Type

Cisco AVVID

IP DSCP

Cisco AVVID

802.1p UP

IEEE

802.11e

UP

Notes

Network Control - 7 - Reserved for network

control onlyInter-Network Control 48 6 7 (AC_VO) CAPWAP control

Voice 46 (EF) 5 6 (AC_VO) Controller: PlatinumQoS Profile

Video 34 (AF41) 4 5 (AC_VI) Controller: Gold QoSprofile

Voice Control 26 (AF31) 3 4 (AC_VI) -

Best Effort 0 (BE) 0 3 (AC_BE)

0 (AC_BE)

Controller: Silver QoS

Profile

Background (Cisco AVVID

Gold)

18 (AF21) 2 2 (AC_BK) -

Background (Cisco AVVID

Silver)

10 (AF11) 1 1 (AC_BK) Controller: Bronze QoSprofile.

The AP and WLC maintain a DSCP to CoS translation table

Both IEEE CoS and Cisco QoS Baseline CoS


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QoS Baseline IEEE 802.1 UP-Based

Traffic TypeWireless

Controller .1P

Setting

(802.11e)

LWAPP DSCP AVVID IEEE802.1p UP

Network control - 7

Inter-network control (LWAPP control,

IEEE 802.11 management)

7 48 (CS6) 6

Voice (Platinum) 6 46 (EF) 5

Video (Gold) 5 34 (AF41) 4

4 26 (AF31)

Voice Control (Silver) 3 18 (AF21) 3

2 10 (AF11) 2

Background (Bronze) 1 2 2

0 0 2

QoS Translation Table: Upstream


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QoS Translation Table: Downstream

QoS Baseline IEEE 802.1 UP-

Based Traffic Type

Max

LWAPP

DSCP

AVVID IEEE

802.1p UP

Wireless

Controller .1P

Setting

(802.11e)

Network control - 7

Inter-network control (LWAPPcontrol, IEEE 802.11

management)

56 (CS7) 6 7

Voice (Platinum) 48 (CS6) 5 6

Video (Gold) 46 (EF) 4 5

32 (CS4) 4

Voice Control (Silver) 24 (CS3) 3 3

16 (CS2) 2 2

Background (Bronze) 8 (CS1) 2 1

0 2 0


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Some Basic Concepts

Each WLAN has a default priority (0-7) that has a bearing on the 802.1p,802.11e/WMM and DSCP markings on the packets

Default priority is assigned by choosing a WLAN to be Platinum, Gold, Silveror Bronze

A Ceiling function will make sure that the 802.11e priority or the equivalentDSCP of a packet on a WLAN is less than or equal to the default priority of aWLAN

A Policing function will make sure that 802.11e UP of a packet isdowngraded to zero if the client does not use TSPEC if Admission Control isMandatory.

6 translation MAPs are used to derive markings as applicable all MAPs areAVVID complaint:

DSCP_to_11e_map (on AP outgoing traffic)11e_to_DSCP_map (on AP incoming traffic)

11e_to_AC_map (on AP outgoing traffic, WMM Compliant)

DSCP_to_1p_map (on controller for incoming traffic)

.1p_to_AVVID_UP and vice-versa (on AP, used only in REAP LocalSwitching/Standalone)


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802.1p DSCP | PayloadDSCP | Payload802.11e

LWAPP Encapsulated

DSCP | Payload802.11eDSCP

802.1p DSCP | PayloadDSCP | Payload802.11e

LWAPP Encapsulated

DSCP | Payload802.11eDSCP802.1p

LWAPP Tunnel

21

34

WLAN QoS mapping

Upper value of mapped DSCP constrained automatically based on WLAN QoS Profile

Upper value of mapped 802.1p value constrained by Wired QoS Protocol setting

Upper value of mapped 802.1p value constrained by Wired QoS Protocol settingDSCP directly mapped from arriving packet DSCP

Upper value of mapped 802.11e UP constrained automatically by WLAN QoS profile

1

2

3

4


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Cisco Implementation

WMM Specification based on IEEE 802.1p UP

Cisco Model based on DSCP and AVVID

In the Cisco deployment model, traffic destined to APs connected to accessports lack a .1p tag

Utilize the Layer 3 DSCP information in order to provide QoS in the absence

of Layer 2 QoS information Layer 3 DSCP is used by APs to ensure packets receive correct over the

air prioritization from the AP to the wireless client.

To maintain the QoS classification across the LWAPP tunnel, the QoSsettings of the encapsulated data packet must be appropriately mappedto the Layer 2 (802.1p) and Layer 3 (IP DSCP) fields of the outer tunnelpacket.

802.1p UP

Outer

IP DSCP

Outer

LWAPP

encapsulatedIncoming

802.1p UP

IP DSCP

Inner.


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AP Controller Traffic On the AP

AP will not send tagged packets as this causes a problem withCisco switches. Hence AP will not copy 802.11e UP incoming to802.1p UP (outer)

On the ControllerGenerate the.1p for the wired side, using the incoming DSCP(outer)

The outer .1p value from AP does not exist, because the APwill be sending NULL VLAN ID frames

IP DSCP

Outer

LWAPP

encapsulated Incoming

802.11e UP

IP DSCP

Inner.


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Reference Diagram

Best Effort Data

Non-WMMClient

WMM

Client

A

BC

E

FUntagged Interface

.1q Tagged Interface

WMM Traffic


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Packet Formats

Link A Untagged Ethernet framesin and out of the controller

Link B tagged 802.1q frames inand out of the controller

Link C

Packets from AP to Controllerare untagged Layer 3 LWAPPpackets

Packets from Controller to APare 802.1q tagged Layer 3LWAPP packets

DataD

S

C

P

DataD

S

C

P

1p

LWAPP DataD

S

C

P

Dot

11

D

S

C

P

1pLWAPP Data

D

S

C

P

Dot

11

D

S

C

P


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Link F Non-WMM Client

AC = VO

AC = VI

AC = BE

AC = BK

DataD

S

C

P

Dot

11

Packets from AP to Client

A UP to AC look up placesthem in the righttransmission queue

Over the air the packetgoes in regular 802.11 Dataformat

Packets from Client to AP

Over the air the packetcomes in as a regular802.11 Data packet


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Link E WMM Client

Packets from AP to Client

A UP to AC look up placesthem in the right transmissionqueue

Over the air the packet goes inQoS Data format with WMM UP

Packets from Client to AP

Over the air the packet comesin as a regular 802.11 QoSData packet

AC = VO

AC = VI

AC = BE

AC = BK

WMM

QoS DataD

S

C

P


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Packet from Link A/B to Link F:Non-WMM Client

a. Put LWAPP Encap

b. Copy inner DSCP to outer DSCP

c. Use DSCP_to_1p_Map to create a .1q

Header

Put on Link C

a. Decap LWAPP header

b. 11e priority = Default

priority of WLAN on which

this non- WMM Client is

associated

c. Use 11e UP to insert the

packet into the right queue

using WMM 11e_to_AC

mappings.

Put 802.11

Data packets

on Link F

Controller

Access Point


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Packet from Link A/B to Link E:WMM Client

a. Put LWAPP Encap

b. Copy inner DSCP to outer DSCP

c. Use DSCP_to_1p_Map to create a .1q

header

Put on Link C

a. Decap LWAPP header

b. Derive 11e UP using

DSCP_to_11e_Map.

c. Apply Ceiling: Check

against WLAN default

priority, modify 11e UP if

higher than def priority

d. Apply Access Policing: If

ACM bit is turned on Apply

policing to derive new 11e

UP. UP = 0 if tspec not used.

UP remains the same if

tspec is used for the STA.

e. Use 11e UP to insert the

packet into the right queue using WMM 11e to AC

mappings.

Put 802.11 QoS

Data packets on

Link E

Controller

Access Point


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Controller to AP Traffic

LWAPP Tunnels SiSiSiSiSiSi

WLAN Controller

AP

Ethernet Switch

LWAPP Encapsulated

DSCP PayloadDSCP

802.1p DSCP Payload802.1p

11

UP (802.1p / 802.11e) IP DSCP

Copy the 802.1p value from the incoming packet.

Police the value to ensure it does not exceed the

maximum value allowed for the WLAN QoS policy

assigned to that client.

Copy the DSCP value from the

incoming packet.


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AP to Non-WMM Client Traffic


WLAN Controller

AP

Ethernet Switch

LWAPP Encapsulated

802.11e DSCP Payload DSCP PayloadDSCP


22

Regular client: place packet in thedefault 802.11 Tx queue for theWLAN QoS policy assigned to thatclient

N/A (original DSCP value is preserved)


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AP to WMM Client Traffic


WLAN Controller

AP

Ethernet Switch

LWAPP Encapsulated



22

WMM Client: Map the DSCP valueof the incoming LWAPP packet tothe 802.11e UP value

Place in the 802.11 Tx queueappropriate for that UP value.

N/A (original DSCP value is preserved)


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Packet from Link F to Link B:Non-WMM Client

a. 11e UP = default priority of WLAN

b. Lookup 11e_to_DSCP_Map on 11e priority

to determine outer DSCP of LWAPP header

c. Apply LWAPP header

Decap LWAPP header

Use DSCP_to_1p_Map to determine

.1p priority using outer DSCP

Prepare dot1q packet with .1p priority

Access Point

Controller

Xmit on

Link A

Xmit on Link B


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Packet from Link E to Link B:WMM Client

a. 11e UP = UP of QoS Data Packet on air

b. Apply Policing: modify UP to 0 if ACM is

Enabled and there are no tspecs for the STA

c. Apply Ceiling: modify UP to make sure that it

is less than or equal to the default WLAN

priority

d Lookup 11e_to_DSCP_Map for 11e UP

to determine outer DSCP of LWAPP header

e. Apply LWAPP header

Decap LWAPP header

Use DSCP_to_1p_Map to determine

.1p priority using outer DSCP

Prepare dot1q packet with .1p priority

Access Point

Controller

Xmit on

Link A

Xmit on Link B


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AP to Controller: Non-WMM Client Traffic

LWAPP Encapsulated

LWAPP TunnelsSiSiSiSiSiSi

WLAN Controller

AP

Ethernet Switch


33

Regular Client: use the 802.11e

UP value for the QoS policyassigned to that client; map thevalue to the DSCP value.


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AP to Controller: WMM Client Traffic

LWAPP Encapsulated


WLAN Controller

AP

Ethernet Switch


33

WMM Client: Police the 802.11eUP value to ensure it does not

exceed the maximum valueallowed for the QoS policyassigned to that client; map thevalue to the DSCP value.


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Controller to Ethernet Switch Traffic

LWAPP Encapsulated


WLAN Controller

AP

Ethernet Switch

802.11e DSCP Payload DSCP PayloadDSCP 802.1p DSCP Payload

44

Map the DSCP value of the original packet

to the 802.1p UP value. N/A (original DSCP value is preserved)


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Knobs

WMM allowed/required: If WMM is allowed, both WMM andnon-WMM clients can associate. If WMM is required onlyWMM clients can associate

ACM enabled: ACM should be enabled only if CAC is to beused. If ACM is enabled policing kicks-in for WMM clients

Protocol Type: None or 802.1p. If 802.1p is selected thepackets on wired tagged interfaces (such as link B) will have.1p markings


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Pivotal Points

Is 802.11 RF Transmission to/from WMM client ?- WMM client = pragmatically trust DSCP (downstream) or802.11e (upstream)

- non-WMM client = no trust, force WLAN QoS level

Is TSPEC CAC configured (aka WLC WIRELESS ->802.11a or 802.11b/g -> Voice CAC or Video CAC ?

- if enabled, WMM client required and one that signals TSPECtraffic access (ADDTS) otherwise related Access Category issent as Best Effort transmission

What is the WLAN defined QoS setting and the QoSProfile 802.1p setting ?

- these setting set the ceiling limit for various QoS translationpoints


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Pivotal Points

WLC/AP translation points tend to demote, not promote,the QoS marking

- WLAN QoS setting and QoS Profile 802.1p setting workcollective to set ceiling for QoS classification translations.

Avoid remarking the DSCP on encapsulated tunnel ifpossible.

- if must be done somewhere, then AP and WLC will still cap thetraffic based on WLAN QoS setting and also the QoS Profile802.1p setting.

- wired network remarking DSCP down will effect resultingdownstream 802.11e eDCF WMM transmission queue, althoughremarking up beyond the WLAN QoS setting and QoS Profile802.1p setting does not. Upstream remarking does not changeanything except wired network handling


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Pivotal Points

HREAP locally switched (aka, AP tagged frames todirect switchport) pragmatically the same, although trustmodel is effective 802.1p CoS marking.

- WMM client (upstream) = 802.11e WMM is translated to 802.1ptagging

- WMM client (downstream) = 802.1p tagging is translated to802.11e AC

- non-WMM client (downstream & upstream) = should betranslated to/from WLAN QoS setting

- Note, WLAN QoS Setting and QoS Profile 802.1p setting still

applies as ceiling limit for translations- Note, user vlan for HREAP local switching needs to be802.1Q/p tagged (aka not native vlan of AP) if QoS operation isdesired.


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Pivotal Points WLC should start with trust CoS & management & ap-manager

should be 802.1Q/p tagging- since WLC does not do DSCP rewrite (eg non tunnel user frames), thenstarting with mls qos trust cos facing WLC to enforce CUWN basedceiling/trust model.

- management & ap-manager interfaces should have non-0 VLANtag number.

AP tunnel frames are native/non-tagged, thus LAP-s should trustDSCP

- AP to WLC frames are native/non-tagged, thus mls qos trust dscp

- exception to this is HREAP local switching, then since enforcement ofCUWN trust model is desired use mls qos trust cos. Expectation is that

WLC is either across WAN with explicit service policy forAPs nativeframe CUWN CAPWAP/LWAPP mgmt & central-switching tunnelframes.


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WLAN QoS

WLC Configuration


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WLAN QoS Profiles

Four ProfilesPlatinum (Voice)

Gold (Video)

Silver (Best Effort)

Bronze (Background)

WLAN QoS Profiles apply forWMM and non-WMM clients


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QoS Profiles

An 802.1p tag can be applied to wired side to allow proper precedence to be applied

to traffic across the entire network infrastructure

If it is none, then there is no dot1p marking applied to frames leaving the WLC

If it is 802.1p, the 802.1p Tag value is the maximum value that the DSCP 802.1p

translation table will apply


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QoS Profile - Platinum


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TSPEC Call Admission Control (CAC)

ACM =TSPEC Admission Control Unless your client supports TSPEC

Do not enable Call Admission Control

Otherwise the AP will transmit yourclient traffic for this AC (eg AC_VO or

AC_VI) at best effort

Load-based AC = RF Channel capacityconsidered

Defaults Max RF Bandwidthrecommended setting is 40 to 60 %


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EDCA Parameters

Different EDCA Parameters are available to optimize the WLANQoS.

These are global (per-band)

Low Latency MAC adjusts retries and queue depths to moreappropriate values for voice

EDCA P t


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WMM:Configured Local Access Class ParametersBack : cw-min 4 cw-max 10 fixed-slot 7 admission-control Off txop 0

Best : cw-min 4 cw-max 10 fixed-slot 3 admission-control Off txop 0Video : cw-min 3 cw-max 4 fixed-slot 2 admission-control Off txop 0Voice : cw-min 2 cw-max 3 fixed-slot 2 admission-control Off txop 0

Spectralink Voice priority:Configured Local Access Class ParametersBack : cw-min 4 cw-max 10 fixed-slot 7 admission-control Off txop 0Best : cw-min 4 cw-max 10 fixed-slot 3 admission-control Off txop 0Video : cw-min 3 cw-max 4 fixed-slot 2 admission-control Off txop 0Voice : cw-min 2 cw-max 3 fixed-slot 2 admission-control Off txop 0

Voice Optimized:

Configured Local Access Class ParametersBack : cw-min 8 cw-max 10 fixed-slot 12 admission-control Off txop 0Best : cw-min 6 cw-max 10 fixed-slot 5 admission-control Off txop 0Video : cw-min 3 cw-max 5 fixed-slot 5 admission-control Off txop 0Voice : cw-min 2 cw-max 4 fixed-slot 2 admission-control Off txop 0SIP stats sip_udp_rx_pkt 0, sip_tcp_rx_pkt 0,

Voice and Video Optimized:Configured Local Access Class ParametersBack : cw-min 8 cw-max 10 fixed-slot 12 admission-control Off txop 0Best : cw-min 6 cw-max 10 fixed-slot 12 admission-control Off txop 0Video : cw-min 3 cw-max 5 fixed-slot 5 admission-control Off txop 0

Voice : cw-min 2 cw-max 4 fixed-slot 2 admission-control Off txop 0SIP stats sip_udp_rx_pkt 0, sip_tcp_rx_pkt 0,

show controllers dot11Radio {0|1}

EDCA Parameters


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Configurations

Voice Deployment


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Cisco Recommendations

Trust DSCP

VoIP traffic is best suited for EF (DSCP 46)

Call-Signaling originally marked AF31, Cisco

recommends migration to CS3


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Controller Adjustments

Disableaggressiveload-balancing

Controllersmust havesamemobility infofor seamless

roaming


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Voice Interface

Enable VLANtagging on thevoice interfaceand other non-

managementinterfaces

Ensure DHCPserver is

configured foreach interface


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SSID Configuration

RecommendedWPA security withTKIP plus CCKMfor authenticatedkey management

Ensure WMM isEnabled

QoS profile is setto Platinum

DHCP Address

Assignment asNOT required

Configure theRADIUS serverswhen using 802.1x


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Platinum QoS Profile

Set the 802.1ptag for thePlatinum QoSprofile to 6


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802.11a Global Parameters

Set the DTIMperiod to 2,where thephone wouldwake up every200ms with a100ms beaconperiod to checkfor incoming

packets Ensure DTPC

is enabled


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802.11b/g Global Parameters

If 802.11b clientsexist in thenetwork, then itis recommendedto enable 11mbps as the

basic rate(mandatory), set18 54 mbps asoptional(supported) and

disable the otherlower data rates

Ensure DTPC isenabled


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802.1x Timeout

If using EAP-FAST or the 802.1x authentication is traversing overa WAN, the 802.1x timeout may need to be increased on thecontroller (default = 2 seconds) in order for the client to obtain thePAC via automatic provisioning

The default timeout on the Cisco ACS server is 20 seconds, whichis the recommended value

To change the 802.1x timeout on the Airespace controller, telnet orSSH to the controller and enter the following command

(Cisco Controller) >config advanced eap request-timeout 20

(Cisco Controller) >show advanced eap

EAP-Identity-Request Timeout (seconds)........... 1

EAP-Identity-Request Max Retries...................... 20

EAP Key-Index for Dynamic WEP....................... 0

EAP-Request Timeout (seconds)........................ 20

EAP-Request Max Retries................................... 2


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ARP Caching

ARP caching can be enabled by the following command

(Cisco Controller) >config network arpunicast enable

(Cisco Controller) >show network

RF-Network Name.......................................... SJC21-VoWLAN

Web Mode....................................................... Disable

Secure Web Mode.......................................... Enable

Secure Shell (ssh).......................................... Enable

Telnet............................................................... Enable

Ethernet Multicast Mode................ ................ Disable Mode: Ucast

User Idle Timeout........................................... 300 secondsARP Idle Timeout........................................... 300 seconds

ARP Unicast Mode......................................... Enabled

Cisco AP Default Master................................ Disable

Mgmt Via Wireless Interface.......................... Enable

Mgmt Via Dynamic Interface........................... Disable

Bridge AP Zero Config.................................... Enable

Bridge Shared Secret...................................... cisco

Allow Old Bridging Aps To Authenticate...... Disable

Over The Air Provisioning of AP's................. Enable

Mobile Peer to Peer Blocking......................... Disable

Apple Talk ........................................................ Disable

AP Fallback ..................................................... Enable

Web Auth Redirect Ports ................................ 80

Fast SSID Change ........................................... Disabled

802.3 Bridging ................................................. Disable


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WMM Clients

WLAN QoS


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Client Capabilities

What to look for in a client review?

WMM Specifications

CCX(v4) Certification

Support for U-APSD, DTPC, TSPEC, CACTransmit Power/Receive Sensitivity

Antenna Gain

802.11 Security Options

E-911 call capability and location support


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CCX Benefits

Feature Benefit

CCKM Support for EAP-TypesLocally Cached Credentials

Means Faster Roams

Unscheduled Automatic Power

Save Delivery (U-APSD)

More Channel Capacity and

Better Battery Life

TSPEC-Based Call

Admission Control (CAC)

Managed Call Capacity for Roaming

and Emergency Calls

Voice MetricsBetter and More Informed

Troubleshooting

Neighbor List Reduced Client Channel Scanning

Load Balancing Calls Balanced Between APs

Dynamic Transmit PowerControl (DTPC)

Clients Learn a Powerto Transmit At

Assisted Roaming Faster Layer 2 Roams


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CCX Information on Controller


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WMM Based U-APSD

Allows synchronization ofsend/receive in oneoperation

AP has perclient buffer

Client initiatestransmission

Improved battery life

Potential to increase the

number of calls each APis capableof handling

U-APSD

NON U-APSD


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DTPC

Set the same transmit power on the AP and on thephones

The Unified Controller advertises its transmit power for

the clients to learn Prevents one-way audio

RF traffic is only being heard in one direction


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TSPEC Based CAC

Defined tothe AP:

Whatpercentage oftraffic will be

reserved fordata and voice?

Benefit: EnsuresThat the NumberOf Active Voice

Calls Do NotExceed TheConfiguredLimits

X
http://www1.us.dell.com/content/products/category.aspx/inspn?c=us&cs=04&l=en&s=bsdhttp://www1.us.dell.com/content/products/category.aspx/inspn?c=us&cs=04&l=en&s=bsdhttp://www1.us.dell.com/content/products/category.aspx/inspn?c=us&cs=04&l=en&s=bsdhttp://www1.us.dell.com/content/products/category.aspx/inspn?c=us&cs=04&l=en&s=bsd


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CAC on the Controller


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Wired QoS

Wired Network QoS


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The Wired QoS Protocol

If it is none, then there is nodot1p marking applied to framesleaving the WLC

If it is 802.1p, the 802.1p Tag

value is the maximum value thatthe DSCP 802.1p translationtable will apply


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Wired Network QoS Recommendations

DSCP 48 (CS6) for LWAPP control (AVVID CoS 6)

DSCP 46 (EF) for VoIP Traffic (AVVID CoS 5)

DSCP 26 (AF31) for Call-Signaling (AVVID CoS 3)

Priority Queue 46 (EF), 48 (CS6) and 26 (AF31) traffic

Trust 48/46/26 and CoS=6/5/3 as applicable

Hand off 48/46/26 to the router to be handled by the

router's QoS policy.


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Access Switch Configuration

Enable QoS globally

mls qos

Trust DSCP on the Switch Port

interface FastEthernet0/1description Access Port to Cisco LWAPP AP-01

switchport access vlan 133

switchport mode access

duplex fullmls qos trust dscp


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Distribution Switch Configuration

Enable QoS globally and include cos-dscp Mapping

mls qos map cos-dscp 0 8 16 26 32 46 48 56

mls qos

Interface Configuration

interface GigabitEthernet1/0/1description Trunk Port to Cisco WLC

switchport trunk encapsulation dot1q

switchport trunk allowed vlan x,y,z (only allow the vlans that need totalk to the controller)

switchport mode trunkmls qos trust cos

channel-group 30 mode on

no shutdown


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wireless qos training

Documents