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Related Manuals for ASCOM VoWiFi System
Summary of Contents for ASCOM VoWiFi System
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Page 1: System Description
TD 92313GB System Description Ascom VoWiFi System 13 December 2010 / Ver. F... -
Page 2: Table Of Contents
3.1.2 H.450 Supplementary Services for H.323 ............16 3.1.3 Session Initiation Protocol (SIP) ................16 3.2 VoWiFi Standards........................17 4 Ascom VoWiFi System Overview................. 18 4.1 Supported Standards ......................20 4.1.1 Ascom i62 VoWiFi Handset ..................20 4.1.2 Ascom i75 VoWiFi Handset ..................20 4.2 System Functions ........................ - Page 3 4.3.3 User Authentication ....................22 4.4 Network Parameter Download ..................23 4.5 Supported Third-Party Products ..................23 4.6 WLAN Planning and Deployment for Ascom VoWiFi System ........23 5 Ascom VoWiFi System Components ................24 5.1 Ascom VoWiFi Handsets...................... 24 5.1.1 Ascom i62 VoWiFi Handset ..................
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Page 4: Introduction
LANs. Using third-party WLAN products as well as in-house developed hardware and software, the system enables data and voice transmission together with seamless roaming. This document gives a general description of the Ascom VoWiFi solution. It briefly describes WLAN and VoWiFi technologies and standards. Figure 1. - Page 5 System Description TD 92313GB Ascom VoWiFi System EAP-TLS EAP-Transport Layer Security Enhanced System Service: Unite modules that handle centralised number planning, remote connection, system supervision, fault handling, group handling, message routing, centralised logging, activity logging, and user access administration. ESSID...
- Page 6 TSPEC Traffic Specification UNII Unlicensed National Information Infrastructure Unite Ascom messaging platform. A generic term for a messaging system that unites different systems, for example System 900, System 9d, and VoWiFi. Unite CM Unite Connectivity Manager: Unite module that enables messaging and alarm handling in a WLAN system.
- Page 7 System Description TD 92313GB Ascom VoWiFi System WMM™ Wi-Fi Multimedia™: offers QoS functionality for WiFi networks. WPA™ Wi-Fi Protected Access™: a set of security features for wireless networks based on IEEE 802.11i. WPA2™ Wi-Fi Protected Access 2™: adds additional security features, the most important of which are pre- authentication, which enables secure fast roaming, and AES, which is the new FIPS standard for data encryption.
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Page 8: Wlan
See section 4.1 Supported Standards for a description of the 802.11 amendments supported by the Ascom VoWiFi system. WLAN Infrastructure There are two types of WLAN topologies: the Ad-Hoc mode and the Infrastructure Mode. The Ad-Hoc mode provides peer-to-peer connectivity where two clients communicate directly with each other via their WLAN cards. -
Page 9: Controller-Based Access Points
Controller and are basically just a radio and an antenna. The Controller handles most of the MAC layer all by itself. The use of controller-based APs enhances operation of the VoWiFi system, makes centralized administration over the WLAN possible, and makes it easy to expand the network. -
Page 10: 802.11A Rf Modulation Standard
System Description TD 92313GB Ascom VoWiFi System The 802.11b and 802.11g specifications include the following restrictions: Radio Band: 2.4 GHz Maximum Data Rate: 11 Mbps (802.11b) 54 Mbps (802.11g) Operating channels: 1–14 (depending on country regulations) ETSI: 1–13 FCC: 1–11... -
Page 11: 802.11N Rf Modulation Standard
System Description TD 92313GB Ascom VoWiFi System The 802.11a specification includes the following restrictions: Radio Band: 5 GHz Maximum Data Rate: 54 Mbps Operating channels: 36–165 (depending on country regulations), see the table below Maximum number of non-overlapping channels: 19–24 (depending on country... - Page 12 System Description TD 92313GB Ascom VoWiFi System • Space-time block coding: A transmitter uses more antennas than signal streams to redundantly transmit the transmit signal. This increases the reliability of the signal at the receiver, and reduces the error rate.
- Page 13 System Description TD 92313GB Ascom VoWiFi System The 802.11n standard defines Modulation and Coding Scheme (MCS), which is combinations of modulation, Forward Error Correction (FEC) coding, and number of spatial streams. The maximum data rate depends on the MCS, channel bandwidth, and GI length. There are 77 MCS values from 0 to 76.
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Page 14: Access Control And Security
System Description TD 92313GB Ascom VoWiFi System Access Control and Security Since the physical layer in a WLAN is broadcast over the air, the normal methods to control a conventional LAN cannot be used. To secure the WLAN from intruders, authentication and encryption are important factors. -
Page 15: Wep
System Description TD 92313GB Ascom VoWiFi System 2.3.3 WEP is a security method built into the 802.11 protocol. It uses a shared key system, this means to configure a key (basically a password) in the AP. In order for a wireless client to connect to the network they must know the key and type it into their software. -
Page 16: Proactive Key Caching (Opportunistic Key Caching)
System Description TD 92313GB Ascom VoWiFi System handover). The amount of time needed for the key exchange is implementation dependant and differs between AP manufacturers. Like WPA, WPA2 has a Pre-Shared Key mode (PSK), WPA2 Personal, designed for SOHO (small office/home office) wireless networks that cannot afford the cost and complexity of an 802.1X authentication server. -
Page 17: Quality Of Service (Qos)
This works well for data traffic but voice, and other multimedia in a WiFi network, is highly sensitive to latency increases and throughput reductions and require QoS functionality. When deploying a VoWiFi system, traffic prioritization is needed to ensure the best possible voice quality. -
Page 18: Tspec Call Admission Control
Other parameters that can affect the power consumption are Beacon period and DTIM. Location in the system will also affect the speech time. For more details, see the document System Planning Ascom VoWiFi System, TD 92408GB. Cisco Compatible Extensions (CCX) CCX is a Cisco proprietary collection of functions and requirements. -
Page 19: Vowifi
The voice signal is digitized, compressed and converted to IP packets and then transmitted over the network. Since voice is a real-time application, a VoWiFi system must ensure that the data streams are reconstructed accurately and that sufficient mechanisms for network delay detection have been implemented. -
Page 20: Vowifi Standards
SAP and SDP are required to support a VoIP call. However, the functionality and operation of SIP does not depend on any of these protocols. VoWiFi Standards The most basic VoWiFi system supports the following WLAN standards: • IEEE 802.11b or IEEE 802.11b/g for Wireless LAN • WMM™ for voice quality (QoS) •... -
Page 21: Ascom Vowifi System Overview
• SIP Proxy Server (in the IP-PBX) (optional) • RADIUS Server (optional) In a small VoWiFi system with few handsets the IMS2/Unite CM is optional. The system can be managed with the WinPDM only, but without an IMS2/Unite CM no messaging or alarm handling is possible and it will be a voice system only. - Page 22 System Description TD 92313GB Ascom VoWiFi System In a large system it is strongly recommended to use an IMS2/Unite CM, and when using shared phones functionality it is required. The IMS2/Unite CM is also required for messaging and alarm functions. An Enhanced System Service (ESS) or a Unite CM is needed if individual passwords for shared phones are used.
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Page 23: Supported Standards
• TSPEC-based CAC • Pre-authentication 1.Ascom i62 VoWiFi handset requires the APs to support WMM for voice power save mode. 2.Ascom i75 VoWiFi handset requires the APs to support WMM for voice power save mode. 13 December 2010 / Ver. F... -
Page 24: System Functions
For use in Cisco WLAN infrastructure, CCKM is supported to speed up the encryption key exchange when roaming in a multi-cell environment. System Functions The Ascom VoWiFi system is designed to enable wireless voice traffic, messaging and alarm handling within an enterprise LAN. For details, see Function Description VoWiFi, TD 92314GB. -
Page 25: Association
System Description TD 92313GB Ascom VoWiFi System 4.3.2 Association Before the authentication can take place, the mobile device need to be associated with an Each AP in the network transmit beacons that the mobile devices listens to. The mobile device, in this case a VoWiFi handset, sends an association request to the AP with the strongest RF signal. -
Page 26: Network Parameter Download
Network parameters, such as ESSID, must be defined in the VoWiFi handset to enable network access. Parameters are loaded to the handset from the WinPDM. For the Ascom i62 VoWiFi handset it is also possible to set the parameters directly on the handset. -
Page 27: Ascom Vowifi System Components
System Description TD 92313GB Ascom VoWiFi System Ascom VoWiFi System Components The Ascom VoWiFi system is created using Ascom developed products, as well as third-party products. This section gives a brief description of the components needed. Ascom VoWiFi Handsets 5.1.1... -
Page 28: Access Point (Ap)
Unite module based on the ELISE2 hardware, designed as an all-in-one solution for centralized management of portable devices. Also, it is an IP messaging gateway responsible for the alarm and message handling between the VoWiFi system and the Unite system. - Page 29 System Description TD 92313GB Ascom VoWiFi System The Device Manager makes it possible to remotely edit parameters and update software in the VoWiFi handsets over the air. It contains a database with all device settings. It can manage large sets of devices that are identical apart from their call numbers.
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Page 30: Unite Connectivity Manager (Unitecm)
TD 92586GB. For a detailed description of the messaging and alarm functions, see Function Description VoWiFi, TD 92314GB. For shared phones functionality, see Function Description Shared Phones in Ascom Systems, TD 92468GB. Unite Connectivity Manager (Unite CM) Unite CM is a web-based tool used for device management, messaging and alarm handling. -
Page 31: Voip Gateway/Gatekeeper
When connecting to an IP-PBX, it is possible to use a SIP Proxy Server in the IP-PBX instead of a VoIP gateway/gatekeeper. It is important to ensure the interoperability between the SIP Proxy Server and the WLAN. See the Ascom extranet > Sales tools > Interoperability. 13 December 2010 / Ver. F... -
Page 32: Administration Tools
System Description TD 92313GB Ascom VoWiFi System Administration Tools Tools for the following VoWiFi functions are defined: • Network administration (VLAN, QoS etc. in Routers, Switches and Access Points) • User administration (WinPDM Windows and/or optional IMS2/Unite CM) • Call control and call routing (Gatekeeper function in the VoIP gateway) •... -
Page 33: Connection To Other Systems
PBX, or directly through third-party H.323 gatekeeper. Interoperability with messaging applications such as the Ascom DECT and Paging system, or other external systems (such as GSM) is done via the Unite system. All messaging to and from the VoWiFi system goes through the Unite module IMS2/Unite CM. -
Page 34: System Solution When Connected To Traditional Pbx
System Description TD 92313GB Ascom VoWiFi System System Solution when connected to Traditional PBX Figure 11. Messaging client Other Unite Messaging Send modules Send Send Access Points VoWiFi Handsets IMS2/ Unite CM Location Server VoIP Gateway Presence Management System PSTN Main PBX Figure 14. -
Page 35: Related Documents
TD 92479GB Function Description Interactive Messaging TD 92168GB Function Description Shared Phones in Ascom Systems TD 92468GB Function Description Push-To-Talk in Ascom VoWiFi System TD 92493GB Function Description Location in Ascom VoWiFi System TD 92607GB Function Description Product Licensing Overview... -
Page 36: Document History
15. • New supported standards and features in i75 VoWiFi Handset. • Appendix A: Ascom Technical Documentation on page 26 September 2008 • Added information about Device Management on page 27. • Added information about location in chapter 7 Connection to Other Systems on page 30. -
Page 37: Appendix A: Ascom Technical Documentation
System Description TD 92313GB Ascom VoWiFi System Appendix A: Ascom Technical Documentation This appendix explains the technical documentation structure and gives a description of each document type. Not all document types exist for all systems. Figure 12. System documents Function 1. - Page 38 System Description TD 92313GB Ascom VoWiFi System System Installation (SI) Primarily explains system-dependent aspects to be considered at system installation and gives an overview of how to install the system. Target groups: technical engineers planning the system and technicians installing it.
- Page 39 On-Line Help (OH) Gives help and information via the PC screen. Repair Manual (RM) For service and repair on some of the Ascom products. The document describes the repair of a product defined by one of three levels: 1st Line Repair Mechanical/cosmetic repair such as change of housing etc.
- Page 40 System Description TD 92313GB Ascom VoWiFi System 13 December 2010 / Ver. F...