Alcatel-Lucent OmniPCX Enterprise R7.1 User manual

Brand: Alcatel-Lucent

Model: OmniPCX Enterprise R7.1

Type: User manual

Voice over WLAN Mobile IP Touch Design Guide R2.0

ESD/ Central Pre Sales / DF/ PH 1/45 January 2007 – Ed 01

Pre-Sales Communication

Voice over WLAN MIPT Design Guide R2.0

OmniPCX Enterprise R7.1

Voice over WLAN Mobile IP Touch Design Guide R2.0

1. Introduction & Objectives ...................................................................................................6

1.1. Operational Components .............................................................................................6

1.1.1. OmniPCX Enterprise Applications Specific Elements ................................................6

1.1.2. VoWLAN Infrastructure (MIPT SVP Server) ...............................................................6

1.1.3. WLAN Infrastructure (Provided by Alcatel-Lucent) ....................................................7

1.1.4. Server Elements (DHCP, TFTP, Management) ..........................................................9

1.1.4.1.. DHCP Server 9

1.1.4.2.. TFTP Server 10

1.1.4.3.. RF Director Management 10

1.1.5. Mobile IP Touch Terminals...................................................................................11

1.1.5.1.. MIPT Description 11

1.1.5.2.. Terminal Options (Chargers, Clips, Pouches) 11

1.1.5.3.. MIPT Configuration Tool 13

1.1.5.4.. MIPT Features 14

1.1.5.4.1. Customizable Rings on MIPT 300 and 600:...............................................14

1.1.5.4.2. Ring Volume on MIPT 600........................................................................14

1.1.5.4.3. Icon Display on MIPT 300 & 600 ..............................................................14

1.1.5.4.4. Diagnostic Mode (in conversation state) provides:......................................14

1.1.5.4.5. Embedded Site Survey evolution (offline mode)..........................................14

1.1.6. NOE features......................................................................................................15

1.1.6.1.1. Dial by Name Feature on MIPT.................................................................15

1.1.6.1.2. Notification Feature on MIPT ....................................................................15

2. Operational Modes and Considerations ..............................................................................16

2.1. Infrastructure Topology Options ..................................................................................16

2.1.1. Direct Mode (Direct-Attach)..................................................................................16

2.1.2. Appliance/Overlay Mode ....................................................................................17

2.1.2.1.. Appliance /Overlay Mode Operation 17

2.2. Quality of Service .......................................................................................................19

2.3. Security ......................................................................................................................20

2.3.1. SSID Broadcast ...................................................................................................20

2.3.2. Authentication & Encryption .................................................................................20

2.3.3. MAC Address Filtering.........................................................................................21

2.3.4. Rogue Activity Detection.......................................................................................21

2.3.5. Isolation Practices................................................................................................21

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Voice over WLAN Mobile IP Touch Design Guide R2.0

2.3.6. Layer 3 & 4 Filtering (ACL & Packet Inspection) .....................................................21

2.3.7. Auxiliary Security Measures ..................................................................................21

3. Design Process for VoWLAN ...............................................................................................22

3.1. Pre Sale Data Collection .............................................................................................22

3.1.1. Physical Diagram (to include existing wireless technologies)...................................22

3.1.2. Logical Diagram .................................................................................................23

3.1.3. Floor Level Maps/Diagrams.................................................................................24

3.2. Customer Specific Application & Design Considerations ...............................................25

3.2.1. SVP Server Cascading .........................................................................................25

3.2.1.1.. SVP Server 100 25

3.2.1.2.. SVP Server 10 and 20 25

3.2.2. Network Topologies ............................................................................................26

3.2.2.1.. Campus definiton 26

3.2.2.2.. Multi-Node definiton 26

3.2.2.3.. Multi-Site definiton 26

3.2.2.4.. Multi-SVP definiton 26

3.2.2.5.. SVP-Cascading definiton 26

3.2.2.6.. Single OXE Node and Multi-SVP Servers (Cascaded or not) 27

3.2.2.7.. Multi-Node and Multi-SVP (Cascaded or not) 27

3.2.2.8.. Layer 2 considerations (SVP Server and MIPT) 28

3.2.2.9.. Layer 3 considerations (SVP and MIPT) 29

3.3. Roaming and Handover..............................................................................................30

3.3.1. Roaming definition..............................................................................................30

3.3.2. Handover definition ............................................................................................30

3.3.3. Handover and Roaming restrictions......................................................................30

3.4. G711 considerations ..................................................................................................31

3.5. G729 considerations ..................................................................................................31

3.6. MIPT 2.0 Specifications ...............................................................................................32

3.6.1. SVP Cascading option .........................................................................................32

3.6.2. G711 and G729A ..............................................................................................32

3.6.3. Security...............................................................................................................33

3.6.4. Roaming and Handover ......................................................................................33

3.7. VoWLAN Multi-Vendor Design in R2.0 .........................................................................34

3.7.1. Converged Wireless Environments (Voice & Data Combinations) ...........................35

3.7.1.1.. Voice alone on 802.11b 35

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Voice over WLAN Mobile IP Touch Design Guide R2.0

3.7.1.2.. Voice on 802.11b, Data on 802.11g (Shared AP & Bandwidth) 35

3.7.1.3.. Voice on 802.11b, Data on 802.11a 36

3.7.1.4.. Partially Overlapping Voice and Data Networks on 802.11b/g (isolated

applicability)

3.8. Predictive Environment Solution Options (Responding to RFx) ........................................37

3.8.1. Manual Calculation of Predictive Coverage ..........................................................37

3.8.2. Predictive Tool Coverage Planning .......................................................................38

4. Environment Verification & Validation...............................................................................39

4.1. Compliance with (R 2.0 Offer).....................................................................................39

4.2. Pre Install VoWLAN Radio Coverage Audit (Site Survey) ................................................39

4.3. Post Install Survey .......................................................................................................40

5. Design Examples ...............................................................................................................41

5.1. Configuration for up to 4 AP (Demo or small area coverage)........................................41

5.2. Configuration for up to 16 AP (No redundancy) ...........................................................41

5.3. Configuration for up to 16 AP (with redundancy)..........................................................42

6. Quotes & Orders................................................................................................................43

7. Reference Documents .......................................................................................................44

7.1.1. VoWLAN section of the Standard Offer: ...............................................................44

7.1.2. VoWLAN section of the PreSales Presentations: .....................................................44

7.1.3. Multi-Vendor section for compatibility:..................................................................44

7.1.4. VoWLAN section of the PCS Process (non-Alcatel-Lucent WLAN infra): ...................44

8. Annex ...............................................................................................................................45

8.1. Site Survey Tool ..........................................................................................................45

Figure 1: MIPT Icons..................................................................................................................14

Figure 2: Dial by Name .............................................................................................................15

Figure 3: Notification.................................................................................................................15

Figure 4: Direct Mode (WLAN Switch) .........................................................................................16

Figure 5: Appliance Mode (WLAN Switch) ...................................................................................17

Figure 6: OmniSwitch 6600-P24 (supporting IEEE 802.3af) .........................................................18

Figure 7: QOS on WLAN solution ..............................................................................................19

Figure 8: Physical Diagram ........................................................................................................22

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Voice over WLAN Mobile IP Touch Design Guide R2.0

Figure 9: IP Addressing Plan ......................................................................................................23

Figure 10: Logical paths for Voice and Data VLANs ....................................................................23

Figure 11: Floor Map (with scale & legend).................................................................................24

Figure 12: Single OXE Node and Multi-SVP Servers.....................................................................27

Figure 13: Multi-Node and Multi-SVP .........................................................................................27

Figure 14: Layer 2 considerations ..............................................................................................28

Figure 15: Layer 3 considerations ..............................................................................................29

Figure 16: G711.......................................................................................................................31

Figure 17: G729.......................................................................................................................31

Figure 18: User Throughput (type of Wall) for 802.11g ...............................................................37

Figure 19: Predictive Method: AP Calculation..............................................................................38

Figure 20: Configuration for up to 4 AP (no redundancy) ............................................................41

Figure 21: Configuration for up to 16 AP (no redundancy) ..........................................................41

Figure 22: Configuration for up to 16 AP (with redundancy) ........................................................42

Figure 23: Site Survey components.............................................................................................45

Figure 24: Survey Result.............................................................................................................45

ESD/ Central Pre Sales / DF/ PH 5/45 January 2007 – Ed 01

Voice over WLAN Mobile IP Touch Design Guide R2.0

1. Introduction & Objectives

It is the intent of this guide to aid Sales Engineers in designing and selling telecommunications solutions

Incorporating Alcatel-Lucent’s Mobile IP Touch (MIPT) Voice over Wireless LAN (VoWLAN) solution (R2.0)

This document has been created specifically in the context of an architectural and technical Pre-Sales

Design Guide approach. It is clearly understood that a client’s choice of solution components and design

options will take into account many factors that will not be explored here (such as financial

considerations, deployment constraints, and business process limitations).

Alcatel-Lucent’s MIPT VoWLAN product offering is a multi-stage solution aimed at meeting customer

demand for converged voice and data wireless environments based on 802.11 technologies. The R2.0

version of the MIPT suite is the result of leveraging existing OmniPCX Enterprise features with OEM

products available in the Alcatel-Lucent portfolio from SpectraLink and others.

Technically speaking, the VoWLAN solution can be built on several centralized WLAN topology schemes

but must always adhere to the Voice over WLAN MIPT solution R 2.0 operational design restrictions (For

more information on design restrictions, see: section

MIPT 2.0 Specifications of this document and the

ALCATEL-LUCENT OmniPCX Enterprise R7.1 Standard Offer document).

1.1. Operational Components

The Alcatel-Lucent MIPT VoWLAN solution offer is comprised of many subcomponents. These components

can be easily grouped into their categories defined by their functions and responsibilities.

1.1.1. OmniPCX Enterprise Applications Specific Elements

At the core of Alcatel-Lucent’s MIPT VoWLAN offer

lays the Alcatel-Lucent OmniPCX Enterprise platform

(R7.1 or greater)

Key to enabling the capabilities of Alcatel-Lucent’s

VoWLAN solution is the NOE features available since

MIPT Rel 2.0 (OmniPCX Enterprise Rel 7.1).

1.1.2. VoWLAN Infrastructure (MIPT SVP Server)

SVP Server 10: can handle up to 10 users

Responsible for synchronizing MIPT terminal

communication flows and managing Access Point

saturation to provide strong QoS; this is a mandatory

MIPT VoWLAN element.

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SVP Server 20 : can handle up to 20 users

Responsible for synchronizing MIPT terminal

communication flows and managing Access Point

saturation to provide strong QoS; this is a mandatory

MIPT VoWLAN element.

SVP Server 100 : can handle up to 500 users

Responsible for synchronizing MIPT terminal

communication flows and managing Access Point

saturation to provide strong QoS; this is a mandatory

MIPT VoWLAN element.

1.1.3. WLAN Infrastructure (Provided by Alcatel-Lucent)

OmniAccess 4302:

Equipped with one Fast Ethernet port (10/100) and

one Gigabit Ethernet port (10/100/1000). Used to

support a maximum of 6 AP in overlay mode only.

There is no POE capability, POE must be provided by

the Data Switch.

OmniAccess 4304:

Used to support a maximum of 4 AP. Equipped with

eight 10/100 Ethernet ports (802.3af capable). Two

different models providing either one 1000base-T

Gigabit uplink (Copper) or one 1000base-SX Gigabit

uplink (Fiber).

OmniAccess 4304

OmniAccess 4308:

Used to support a maximum of 16 AP. Equipped with

eight 10/100 Ethernet ports (802.3af capable). Two

different models providing either one 1000base-T

Gigabit uplink (Copper) or one 1000base-SX Gigabit

uplink (Fiber). Imbedded Stateful Inspection

firewall options allow for robust security

installations.

OmniAccess 4324:

Used to support a maximum of 48 AP. Equipped with

twenty-four 10/100 Ethernet ports and two GBIC

uplink modules for flexible LAN applications.

Imbedded Stateful Inspection firewall options allow

for robust security solutions.

OmniAccess 4308

OmniAccess 4324

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OmniAccess 6000:

Four slot modular chassis used to support a

maximum of 512 AP. Equipped with up to seventy-

two 10/100 Ethernet ports and six GBIC uplink

modules for flexible LAN applications. Imbedded

Stateful Inspection firewall options allow for robust

security solutions.

OmniAccess 60/61:

Single network (802.11a

or 802.11b/g) Wi-Fi Access

Points for use with OmniAccess WLAN controllers.

WLAN 60 model requires external special purpose

antenna (WLAN 61 offers only internal antenna

option.)

OmniAccess AP41:

Single network (802.11a

or 802.11b/g) Wi-Fi Access

Points for use with OmniAccess WLAN controllers.

Single, integral, tri-band, omni-directional antenna

with articulating movement. Non-detachable.

OmniAccess AP65:

Flexible multifunction Access Point provides

simultaneous access to both 802.11a

and 802.11b/g

networks. Dual, integral, tri-band, high-gain, omni-

directional antennas with 180 degrees rotational

movement. Non-detachable.

OmniAccess 70

Flexible multifunction Access Point provides

simultaneous access to both 802.11a

and 802.11b/g

networks. Supports built-in and external special

purpose antenna.

OmniAccess 6000

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OmniAccess 80

Flexible multifunction Access Point provides

simultaneous access to both 802.11a

and 802.11b/g

networks. Designed for outdoor and extreme, all-

weather deployment. Supports a variety of

attachable antennas and supports an integrated PPP

over Ethernet client for remote deployments over

service provider networks.

Alcatel-Lucent openly recognizes the challenges faced by customers with existing 802.11 network

implementations. For this reason, Alcatel-Lucent also seeks to support Mobile IP Touch - Voice over

Wireless Local Area Network solutions on a variety of approved third-party infrastructure architectures.

SVP compliant Infrastructure vendors such as, 3Com, Cisco, Colubris, Nortel, Symbol, Trapeze, etc. can

possibly be used in lieu of Alcatel-Lucent’s OmniAccess WLAN products. Solutions leveraging third-party

Wi-Fi infrastructures (such as those previously mentioned) must be reviewed and approved by Alcatel-

Lucent’s Bid Desk (PCS) for applicability and support.

1.1.4. Server Elements (DHCP, TFTP, Management)

1.1.4.1. DHCP Server

Customers have two IP address allocation schemes to choose from for MIPT handsets, static mode and

dynamic mode. Static mode operation is very simple and requires no expanded explanation. Terminals

are simply programmed manually with IP addresses, subnet mask, default gateway, TFTP server, and SVP

Server information. Optionally, MIPT Terminals can be configured in a dynamic mode via standard DHCP

server options.

Dynamic mode is recommended due to ease of use and speed of reconfiguration. An external or an

internal DHCP server (OmniPCX Enterprise) can be used for all MIPT VoWLAN solutions. Alcatel-Lucent

does not currently offer the DHCP Server hardware platform and recommends the customers or business

partners source this equipment from their usual PC Server supplier.

Alcatel-Lucent has validated the following DHCP Server software platforms for use with MIPT VoWLAN

solutions.

Validated DHCP Server software platforms.

Windows 2000 (Server) DHCP turbo by Weird Solutions

Linux DHCP Server

Important remark: In addition to standard and common parameters (IP Address, Subnet Mask, Default

Gateway IP Address, TFTP Server IP Address), the external DHCP server must be able to

provide the MIPT terminal with the IP address of the SVP Server. This makes the optional

DHCP fields for “Vendor Specific Options” mandatory for use with MIPT handsets. For

Windows 2000 Server, the Vendor Specific Option field is known as “Special Option N°151”

(for the SVP Server).

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Voice over WLAN Mobile IP Touch Design Guide R2.0

1.1.4.2. TFTP Server

A TFTP Server is mandatory for all MIPT VoWLAN solutions. The TFTP Server is responsible for supplying

Binary and Text configuration files to the MIPT handsets.

TFTP Server functions can be hosted from the OmniPCX Enterprise Communication Server or external.

(The SVP Server is not permitted to host TFTP Server operations due to TCP port conflicts).

There are no unique TFTP Server requirements beyond standard TFTP protocol specifications to support

MIPT terminals. It is possible to combine TFTP Server and DHCP Server functions on a single external

platform.

Alcatel-Lucent has validated the following TFTP Server platforms for use with MIPT solutions.

Validated TFTP Server software platforms.

3Com TFTP Server (3CDaemon) V2.0r10 Cisco TFTP Server

TFTP turbo by Weird Solutions Solar Winds TFTP

Linux TFTP Server

1.1.4.3. RF Director Management

The initial goal of RF Spectrum Management is to configure and calibrate radio settings for the wireless

network. After the radio network is operational, the goal of RF Spectrum Management changes to that of

tuning and adjusting radio parameters in order to maintain a high degree of performance. With Alcatel-

Lucent, RF Spectrum Management is largely automatic, requiring little configuration or intervention from

the administrator. Key components of Alcatel-Lucent’s RF Director solution are:

• Calibration: Used continuously throughout the life of a wireless network; Calibration

functions allow network administrators to optimize power and sensitivity settings of the

network on an antenna by antenna basis.

• Optimization:

Auto Radio Resource Allocation: allows individual access points to monitor for RF

changes and, in conjunction with Calibration information, make appropriate channel

assignment changes.

Self Healing: In the event that an AP fails, surrounding APs can automatically

increase their transmit power level to fill in any gaps.

Load Balancing: ensures optimum performance by automatically spreading client

association in an equitable manner to avoid the premature saturation of a single AP.

• RF Monitoring:

Coverage Hole Detection: Continuous monitoring of client data access and error rates

provides for the identification of coverage holes or areas of diminished service.

Interference Detection: notifies network administrators when localized interference

becomes sufficient to cause performance degradation.

Event Threshold Configuration: provides the ability to configure event thresholds to

notify the administrator when certain RF parameters are exceeded.

• Wireless Intrusion Detection: can identify and defeat a wide assortment of DoS attacks

aimed at Wi-Fi networks.

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Voice over WLAN Mobile IP Touch Design Guide R2.0

1.1.5. Mobile IP Touch Terminals

1.1.5.1. MIPT Description

Alcatel-Lucent makes two MIPT models available, one each for office and industrial use. The

performance of these two handsets is very similar but their designs and options are focused for use in

specific environments. Both of these terminals are products of an OEM partnership between Alcatel-

Lucent and SpectraLink.

For office environments Alcatel-Lucent proposes the MIPT

300.

Dimensions : 5.5” x 2.0” x 0.9” (14 x 5.1 x 2.3 cm)

Weight: 4.2 ounces (119 grams)

For industrial environments (manufacturing facilities,

warehouses, and other harsh environments) Alcatel-Lucent

proposes the MIPT 600 with special “Push-to-talk”

function.

Dimensions : 5.9” x 2.2” x 1.0” (15 x 5,6 x 2,5 cm)

Weight: 6.0 ounces (170,1 grams)

Both terminals employ a standard 12 button keypad (0-9, *, #).

Four soft keys are supplied on MIPT handsets:

• Menu key: access to phone features

• Function key: access to a customization menu

• Navigation keys (Qty-2): selection keys for menu navigation.

The Ni-MH battery supplied with MIPT handsets is capable

of operating for 4 hours of talk time and supporting 80

hours of standby operation.

1.1.5.2. Terminal Options (Chargers, Clips, Pouches)

To complement Alcatel-Lucent’s MIPT handsets offerings, Alcatel-Lucent includes in its catalogue a list of

optional components for use directly with the MIPT 300 and MIPT 600.

Clothing/Belt Clips:

The MIPT 300 and MIPT 600 each have an option for a

model specific Clothing Clip.

Pouches: (MIPT 600 only)

For handset protection and ease of transport, the MIPT 600

can be equipped with one of two optional pouches (with or

without keypad cover.)

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Voice over WLAN Mobile IP Touch Design Guide R2.0

Swivel Clip for MIPT 300:

Offering easy removal of battery, interchangeable clips for

simple attachment to clothing.

Charging Stands:

The MIPT 300 and MIPT 600 each have an option for a

model specific Charging Stand. (For instance when ordering

from Actis, “the MIPT 300/600 Pack” provides the selected

MIPT set + the Charging Stand)

MIPT Charger Plug:

The MIPT 300/600 Charger Plug provides the AC-DC

transformer feeding the Charging Stand. The power plug is

country dependent.

Gang Charger: (MIPT 600 only)

To support multiple battery charging operations for MIPT

600 terminals, the four-port Gang Charger accepts

batteries (not terminals.)

Shown with two batteries.

Dual Charger Stand:

Available for MIPT 300 and for MIPT 600.

Charging priority provided first to the Phone Slot.

The spare battery starts charging when the phone battery

is fully charged.

Battery Packs:

Available for MIPT 300 and for MIPT 600.

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Voice over WLAN Mobile IP Touch Design Guide R2.0

1.1.5.3. MIPT Configuration Tool

Configuration cradle:

One MIPT set configuration at a time

One slot per MIPT set type.

MIPT set configuration via Windows-PC (RS-232 serial

interface to PC).

Direct upload or download from/to the MIPT set flash

memory.

Store multiple configurations to support different user

profiles

The cradle has 3 levels of device configuration (global or

individual).

Each level represents a particular configuration file that

can be loaded from or sent to a MIPT set.

System Level

Changes configuration parameters/settings common to all

phones. E.g., WEP/WPA Keys, SSIDs, Subnet Mask, etc.

Group Level

Changes configuration parameters/settings common to a

group of MIPT sets. Ex for MIPT 600: PTT (Push To Talk)

enable/disable or PTT channels.

Phone Level

Changes configuration parameters/settings unique to an

individual telephone. E.g., extension numbers, static IP

addresses, and/or ring tones.

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1.1.5.4. MIPT Features

1.1.5.4.1. Customizable Rings on MIPT 300 and 600:

Ring Tone, Ring Delay, Ring Cadence and Vibrate Cadence parameters can all be adjusted independently

to meet individual call notification preferences.

1.1.5.4.2. Ring Volume on MIPT 600

Ring Volume is adjustable only on the MIPT 600.

1.1.5.4.3. Icon Display on MIPT 300 & 600

Icons are available on the MIPT 300/600 display to indicate the present RF Signal Strength and the

Battery Power Level.

Figure 1: MIPT Icons

1.1.5.4.4. Diagnostic Mode (in conversation state) provides:

MAC address (4 last digits) of the associated Access Point, RF Channel and strength level.

Statistics (retries, lost packets, jitter, etc.)

1.1.5.4.5. Embedded Site Survey evolution (offline mode)

Displays the 4 strongest AP MAC addresses (4 last digits) and channel number. A sub-menu allows to show

neighbouring APs & SSIDs out of the VoIP network. (This Survey mode does not replace the Site Survey

Tool).

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1.1.6. NOE features

Since OmniPCX Enterprise Rel 7.1 the MIPT set has integrated NOE feature (Dial by Name, Notification for

Messaging, etc.) and as a result can be globally considered as an IP Touch set, but limited by its

ergonomics. For more details see Feature List and Product Limits. NOE protocol has replaced H323

operation and as a result there is no need for Gatekeeper anymore. The Mobile IP Touch set is now

defined as “MIPT” in the Com Server configuration and as a result the previous “Remote Extension”

configuration (MIPT Rel 1.x) is not used anymore.

1.1.6.1.1. Dial by Name Feature on MIPT

Figure 2: Dial by Name

1.1.6.1.2. Notification Feature on MIPT

Figure 3: Notification

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Voice over WLAN Mobile IP Touch Design Guide R2.0

2. Operational Modes and Considerations

The Alcatel-Lucent VoWLAN solution presents several topologies, call handling and performance options

to meet customer demands. Many of these options are described below.

2.1. Infrastructure Topology Options

Being as no two customer network environments are exactly the same, it is critical for technology such as

VoWLAN to possess a great degree of flexibility. Alcatel-Lucent’s MIPT solution is not exempt from this

requirement. The following section highlights some MIPT architectural adaptabilities.

2.1.1. Direct Mode (Direct-Attach)

In Direct Mode operation, the Access Points are directly connected to the 10/100 Ethernet switch

interfaces on an Alcatel-Lucent OmniAccess Wireless Switch (model: OA4308, 4324 and/or 6000.) These

WLAN Switches have the ability to provide Power over Ethernet (IEEE 802.3af) to Access Point (AP) on all

Ethernet ports (Power Class 3 for all ports simultaneously.)

This type of operational mode is desirable and advantageous in the following situations:

1. In small buildings or locations where cables lengths are less than 100m (in order to effectively

leverage integrated IEEE 802.3af capabilities.)

2. Where there is no existing data network or the existing data network is already operating at

maximum capacity.

3. When existing data network elements lack the ability to provide sufficient IEEE 802.3af power to

Access Points.

4. When wireless LAN Access Point controller redundancy is not necessary.

5. For small WLAN environments requiring only a small number of Access Points.

6. To meet requirements for completely independent voice and data networks/backbones.

Figure 4: Direct Mode (WLAN Switch)

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Voice over WLAN Mobile IP Touch Design Guide R2.0

2.1.2. Appliance/Overlay Mode

In Appliance Mode operation, Access Points are not directly attached to Alcatel-Lucent OmniAccess

Wireless Switches. In this type of operational mode, the Alcatel-Lucent OmniAccess Wireless Switch acts

only as an Access Point Controller and does not directly host AP via local 10/100 ports.

This type of operation mode can be highly desirable and advantageous in the following situations:

1. When existing data network elements are present and capable to supporting WLAN Access Points

and traffic.

2. In large and/or multi-floor buildings where cables lengths are commonly in excess of 100m from

the data switching centers and wiring closets to Access Points, thus causing problems for Inline

Power over Ethernet (IEEE 802.3af.)

In cases such as this, localized power options can be proposed to meet or eliminate the distance

limitation and power problems.

3. When system failover/redundancy of the WLAN controller elements is highly desired.

2.1.2.1. Appliance /Overlay Mode Operation

While OmniAccess Wireless Switches can support Direct Mode operation, they can also be used for

Appliance Mode scenarios. In this way, Access Points can be directly connected to an existing LAN

infrastructure Ethernet data switch (from Alcatel-Lucent or third party supplier.) These Access Points can

be configured to automatically connect to multiple OmniAccess Wireless Switch (one at a time) using a

tunnel protocol optimized for lightweight access points management and traffic transport (GRE, IPSec,

and/or L2TP.)

This type of operational mode with OmniAccess Wireless Switches allows for a low cost redundancy

proposal for small configurations, particularly with the OmniAccess 4308 model. By being aware of the IP

addresses of multiple OmniAccess Wireless Switches, Access Points can perform near-immediate transfer

of management responsibilities to backup OmniAccess Wireless Switches and in so doing maintain

operation during periods of partial network outage and/or OmniAccess Wireless Switch maintenance.

Since Access Points are not directly attached to OmniAccess Wireless Switches, network connectivity and

power options must be provided by an Ethernet switch or other source. It is important to ensure that the

desired Ethernet switch is capable of supporting the QoS requirements of the VoIP traffic that it will be

forced to carry. The tunnel path between the Access Point and the Wireless Switch must receive high

priority to ensure a sufficient level of voice quality.

Figure 5: Appliance Mode (WLAN Switch)

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Voice over WLAN Mobile IP Touch Design Guide R2.0

We can also mix both modes (Direct and Appliance) but for backup purpose the best solution remains the

Appliance mode.

Figure 6: OmniSwitch 6600-P24 (supporting IEEE 802.3af)

Since the Access Points can not benefit from the Inline Power capabilities of the OmniAccess Wireless

Switch, the Ethernet switch must be capable of supplying sufficient and standard format power (full 15W

limit of IEEE 802.3af.) In the event that this can not be achieved, several options are available:

• The OmniAccess Access Point can be supported via a localized

external power supply. This AC/DC transformer is the same

type of device used to recharge batteries in PDAs, mobile

phones, and some laptop computers. While an available

option, the use of localized power is discouraged due to the

likely location of Access Point placement and this proximity to

AC outlets, fire-code safety concerns, and power autonomy costs.

External Power Supply

• Inline Power Injectors can be used to provide IEEE 802.3af power to

individual Access Points. These low-cost, single port (one in, one out)

injectors can be used in situations where only one or a few devices

require power. These devices require a local AC outlet

connection to produce IEEE 802.af power and then inject

this power along with the Ethernet traffic that pass

transparently through it.

Inline Power Injector

Power Patch Panel

• Much like the above discussed Inline Power Injector, Inline Power

Patch Panels can be used to achieve the same effect when more than

a few devices require IEEE 802.3af power. Alcatel-Lucent

offers Power Patch Panels in 6, 12, and 24 port varieties.

ESD/ Central Pre Sales / DF/ PH 18/45 January 2007 – Ed 01

Voice over WLAN Mobile IP Touch Design Guide R2.0

2.2. Quality of Service

The QoS management responsibilities are shared between the SVP Server and the OmniAccess

infrastructure components. The first responsibility of the SVP Server is to control the number of

simultaneous voice calls permitted per Access Point. While the absolute maximum limit of simultaneous

voice conversations per Access Point is 14, assuming ideal conditions, the actual limits enforced per

Access Point must take competition (bandwidth and radio spectrum sharing with data clients) and signal

quality (distance from AP and radio obstacles/interference) into consideration.

The SVP Server is also tasked with the coordination and synchronization of MIPT traffic on each AP in

order to avoid the collision of MIPT voice flows with each other and other traffic forms. These

coordination and synchronizations activities are performed with a limited congestion avoidance but

without traffic shaping mechanisms. This makes SVP efforts towards QoS, in the R 2.0 offer, a partial

prioritization function.

(No current VoWLAN offer supports better QoS facilities than the SpectraLink solution employed by

Alcatel-Lucent. The SVP server becomes a “de facto” standard.)

Summary of SVP Server Functions

- CAC : Call Admission Control (Maximum quantity of Voice calls per AP).

- Flow prioritization at AP level for Downlink Voice flows (SRP protocol).

- Voice prioritization at radio level for uplink and downlink (MAC).

- Time Delivery reducing upstream messages collision.

- Battery saving (due to Time Delivery).

- Upstream and Downstream Voice packets re-synchronization.

Infrastructure components, such as the OmniAccess Wireless Switch and/or OmniAccess Wireless

Appliance possess the ability to assure certain levels of prioritization of voice traffic over data traffic.

This can only be performed in a single direction (using Weighted Fair Queuing), from the infrastructure

towards the MIPT handset. No infrastructure facility (such as IEEE 802.11e) is presently included in

Alcatel-Lucent’s MIPT VoWLAN R2.0 solution to provide for QoS from the MIPT handset towards the wired

LAN. For prioritization from the MIPT handset in the wireless environment towards the wired LAN, only

proprietary methods and adaptations of the IEEE 802.11 PIFS (PCF Interframe Spacing) option are

currently offered (Further information on these proprietary methods can be found in the SpectraLink SVP

Whitepaper).

Figure 7: QOS on WLAN solution

As with all other forms of Voice over IP, strict prioritization on the wired LAN is essential in order to

eliminate the effects of traffic competition on quality. For this reason, VLAN prioritization using IEEE

802.1q (VLAN priority option) and traffic prioritization using 802.1p by the data network elements are

considered mandatory for connections between infrastructure components and the OmniPCX Enterprise.

This is especially important for connects to devices like the SVP Server, which can not current stamp

packet priority labels on traffic.

ESD/ Central Pre Sales / DF/ PH 19/45 January 2007 – Ed 01

Voice over WLAN Mobile IP Touch Design Guide R2.0

2.3. Security

Security is always a sensitive topic to discuss, and opinions on how best to provide for it vary greatly

from one engineer to the next. With this in mind, Alcatel-Lucent is constantly developing the list of

security options available within the MIPT VoWLAN solution offer to satisfy as many different opinions as

possible.

For the R 2.0 solution offer, Alcatel-Lucent makes the following security recommendations:

2.3.1. SSID Broadcast

When designing and managing a Wireless LAN, engineers must make calculated compromises

between performance and ease of use. One such decision is that of whether or not to broadcast

the SSID (Service Set Identifier) of a wireless network. Broadcasting the SSID allows clients to

“scan” for available network and then attempt to join them. This eliminates the need for users

to explicitly know the name of the network that must be defined in their 802.11 client

configuration, since it can be learned from the over-the-air broadcasts (excluding MIPT terminals

that must be configured manually by design.) Obviously, not broadcasting the SSID provides the

opposite: users must know the SSID.

In the above mentioned way, it is commonly thought that we can offer a limited realm of security

simply by not broadcasting the SSID of the Wi-Fi environment dedicated to VoWLAN activity. In

truth, this practice is often far more troublesome to network administrators than it is to network

attackers. The advantages of SSID broadcast usually far exceed the threat of visibility it offers.

Since all MIPT terminals must be manually configured with an SSID, the decision to enable or

disable SSID broadcast is of little consequence to Alcatel-Lucent MIPT terminals. There is no

impact to ease of use or functionality presented by the state of SSID broadcast. Alcatel-Lucent

recommends that customers maintain their current or desired security policies governing this

topic.

2.3.2. Authentication & Encryption

At present, for the MIPT R 2.0 offer, Alcatel-Lucent provides authentication and encryption

options based on WEP (Static Key),WPA-PSK and WPA2-PSK (802.11i / AES encryption). This

means that, if selected, wireless traffic for VoWLAN can be encrypted based either on RC4

ciphering techniques (with or without TKIP) or on AES (WPA2), and “Shared Key” authentication

mechanisms. Pre Shared Keys must be manually entered in each MIPT terminal at installation. In

the case of WPA/WPA2-PSK implementation, the Pre Shared Key is used for initial authentication

and as the seed for Temporal Key Integrity Protocol key rotations. No other authentication

and/or encryption options are presently available (i.e. 802.1x authentication.)

WEP is recognized as being a weak security option due to the static nature of the encryption key.

Derivation of the key is possible through simple passive scanning techniques and data analysis.

To counter this problem, the Wi-Fi Alliance has defined a standard known as WPA. WPA, in

reality, is WEP enhanced with TKIP key rotation. This prevents key derivation through passive

scanning and brute force attacks. WPA-PSK can be implemented in most infrastructure

environments through simple software upgrades, making it a universally available, simple and

effective scheme for content protection.

Alcatel-Lucent strongly recommends the use of WPA2 (or at least WPA) in order to provide the

highest levels of confidentiality and network security. The password length must be greater than

twenty characters in order to avoid the brute force attacks.

ESD/ Central Pre Sales / DF/ PH 20/45 January 2007 – Ed 01

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Alcatel-Lucent OmniPCX Enterprise R7.1 User manual

Alcatel-Lucent OmniPCX Enterprise R7.1 User manual

Alcatel-Lucent OmniPCX Enterprise R7.1 User manual

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