Overview

C H A P T E R 1

This document begins by identifying the specific radio environmental values that are needed for a successful voice deployment.

Note Cisco offers a Cisco Aironet Wireless Site Survey class for technical individuals who will be performing site surveys for wireless LAN solutions. This white paper does not replace the information in the site survey class. Cisco recommends that wireless LAN survey technicians take the Aironet Wireless Site Survey class as a requisite. Cisco also recommends that technicians study the Cisco Wireless IP Phone 7920 Deployment Recommendations before studying this white paper.

There are two types of wireless LAN VoIP surveys:

•A survey performed with Wireless IP Telephony (WIPT) handsets

•A survey that simulates WIPT operation

Cisco recommends that, if possible, you install the VoIP network following AVVID design guidelines before surveying for a WIPT network.

Tip Click this link to browse to a library of AVVID design guides:

http://www.cisco.com/warp/public/779/largeent/it/ese/srnd.html

Recommendations for Successful VoIP Surveys

The most effective surveys are performed using Cisco access points and Cisco WIPT handsets on active calls through Cisco’s Call Manager. In the site survey, it is important that you test performance from the source to the end point and also from the end point to the source. For example, your WIPT site survey should use a wired VoIP phone (such as a Cisco 7960) in the core of the network to a WIPT (such as a Cisco 7920) handset with a live conversation going in both directions. The Cisco 7920 WIPT handset enables you to audibly monitor the quality of the call. Cisco also recommends that you use the customer’s actual handset configuration when performing the survey.

Cisco considers it necessary to re-survey for voice at a site that has a trouble-free WLAN data network. Voice traffic is isochronous—to be usable, it must be transmitted without delay. Voice traffic has strict resource requirements for guaranteed bandwidth, low latency, low jitter, and low packet loss. The 7920 G.711 codec voice packets require a guaranteed bandwidth of 80 kbps. The G.711 packets have a

160-byte payload plus a 40-byte RTP/UDP/IP protocol overhead. Typically, voice packets are sent every 20 milliseconds (ms), and a corresponding service rate is expected from the network by the voice application. A delay or loss of two or more contiguous voice packets is generally noticeable as quality

Site Survey Guide for Deploying Cisco 7920 IP Phones

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7920 specifications

Cisco Systems, a leading player in the global networking and communications technology sector, designed the Cisco 7920 Wireless IP Phone for mobile professionals seeking seamless connectivity in various environments. Primarily aimed at enhancing communication within enterprise settings, this wireless device offers a plethora of features that cater to the specific needs of businesses.

At the core of the Cisco 7920 is its robust wireless functionality. It operates on IEEE 802.11b/g wireless protocols, allowing users to connect effortlessly to Wi-Fi networks. This flexibility enables employees to communicate effectively from various locations within an office space, promoting mobility and collaboration without being tethered to a desk.

The ergonomic design of the Cisco 7920 prioritizes user comfort. Its lightweight casing and intuitive button layout ensure that users can navigate the interface with ease. The device is equipped with a vibrant color display, allowing for clear visibility of caller ID, call status, and menu options, enhancing the user experience further. Additionally, the handset supports a wide variety of languages, making it suitable for global teams.

In terms of features, the Cisco 7920 is loaded with advanced capabilities. It supports voice over IP (VoIP), delivering high-quality audio and ensuring reliable communication. Users benefit from features like a contextual menu, call hold, transfer, conference calling, and voicemail access on the go. The phone also offers a wide range of ringtones, allowing customization to suit personal preferences or company branding.

Security is a crucial aspect of modern telecommunications, and the Cisco 7920 does not fall short. It incorporates industry-standard security protocols such as Wired Equivalent Privacy (WEP) and Wi-Fi Protected Access (WPA), safeguarding communications from potential threats.

Moreover, the Cisco 7920 integrates seamlessly with Cisco Unified Communications Manager, enabling centralized management and control. This integration ensures that IT departments can deploy, manage, and troubleshoot devices efficiently, streamlining operations while ensuring optimal performance.

In conclusion, the Cisco 7920 Wireless IP Phone stands out as a versatile communication tool designed for the fast-paced workplace. Its combination of wireless connectivity, ergonomic design, advanced features, and robust security makes it an essential accessory for businesses looking to elevate their communication strategies. With its established reputation, Cisco continues to support companies in achieving seamless connectivity and effective collaboration.