Cisco Systems 7920 IP manual Interconnecting WLANs to Cisco Campus Infrastructure

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The following is an example of configuring the QBBS element in beacons on Cisco IOS Software−based APs:

Beyond just having queuing and setting packets with the correct DiffServ markings, delay and jitter need to be taken into consideration. This is especially true for upstream traffic since there is no queuing among clients on the 802.11b side of the AP. The simplest way to accomplish this is to stay within the guidelines for the number of WLAN clients per AP. Exceeding this creates additional opportunities to introduce packet delay and jitter.

For more details about deploying QoS in WLAN networks, refer to the Wireless Quality−of−Service Deployment Guide.

Interconnecting WLANs to Cisco Campus Infrastructure

This section contains pre−tested, recommended configurations. This helps you to quickly and simply build and deploy a Cisco approved network design using Catalyst 3550 and 2950 series Intelligent Ethernet Switches.

By following the information in this section, you can create a Cisco AVVID Network Infrastructure to run converged voice, video, and data network over IP, with due consideration for QoS, bandwidth, latency, and high performance in demand by Cisco AVVID Network Infrastructure solutions.

The AP template should be configured when a single AP is attached to a port. This template adds all the baseline security and resiliency features of the standard desktop template, but for the Catalyst 3550, it also optimizes the performance of the attached AP.

Ethernet switch ports can transmit and receive at 100Mbps. However, APs, depending on the type (802.11b), only have a practical throughput of 6Mbps or less. This throughput mismatch means that with a burst of traffic, the AP needs to do packet drops, which adds an excessive processor burden to the unit and affects performance.

By taking advantage of the Catalyst 3550 policing and rate limiting capabilities, the task of dropping excessive packets is removed from the AP. This template rate limits the port to the practical throughput of 6M and guaranteeing 1Mbps for high priority voice and control traffic. Because of this prioritization, this template can be used with wireless IP telephones.

The 3550−24−PWR in−line power switch can be used to provide power to the AP.

This template helps create a secure and resilient network connection with the following features:

∙Return Port Configurations to Default ￿ Prevents configuration conflicts clearing any pre−existing port configurations. This allows you to start with a clean slate.

∙Disable Dynamic Trunking Protocol (DTP) ￿ Disables trunking, which is not needed for a connection to an AP.

Cisco − Wireless IPT Design Guide for the Cisco 7920 IP Phone

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Contents Table of Contents Prerequisites IntroductionRequirements Components Used Cisco 7920 IP Phone OverviewWlan Overview RF Overview Site Surveys and Design RecommendationsRssi VoIP QoS∙ Delay Variation Jitter Not to exceed 30ms Security for the Cisco 7920 and Wlan Networks Number of 802.11b Devices per AP Network SizingNumber of 802.11b IP Phones per AP Page Numbers of 802.11b Phones per Layer 2 Subnet or Vlan Understanding Roaming Terminology Understanding Layer 2 and Layer 3 RoamingLayer 2 Roaming Page Layer 3 Roaming VLANs Wlan QoS for VoIP Page Page Page Interconnecting WLANs to Cisco Campus Infrastructure Connecting APs to the Catalyst 3550 SMI or EMI Connecting APs to the Catalyst 2950 SI Connecting APs to the Catalyst 2950 EICaveats and Limitations Designing Around the Lack of Layer 3 Roaming Call Admission ControlOther Caveats and Limitations Related Information

7920 IP specifications

The Cisco Systems 7920 IP phone represents a significant advancement in wireless communication technology, designed specifically for enterprises that require mobility and efficiency in their communication systems. This versatile device integrates seamlessly into a Cisco IP telephony network, allowing users to maintain connectivity while on the move, which is essential in fast-paced business environments.

One of the key features of the Cisco 7920 is its robust wireless capabilities. Operating on the IEEE 802.11b/g Wi-Fi standards, it provides a reliable connection to corporate networks, ensuring that users can access voice, data, and video services without being tethered to a desk. The phone supports dynamic call handling and features a responsive LCD display that enhances user interaction, making it easier to navigate menus and manage calls.

The Cisco 7920 also offers exceptional sound quality, thanks to its advanced audio technology. With Wideband audio support, users can experience clarity in conversations, which is particularly important in environments where clear communication is vital. The phone is equipped with noise-canceling capabilities that reduce background noise, allowing users to focus on their conversations without distractions.

Security is another critical aspect of the Cisco 7920. The device supports several security protocols, including WPA and WPA2, ensuring that all communications are encrypted and secure. This is crucial for organizations that handle sensitive information and need to comply with industry regulations.

Additionally, the Cisco 7920 features an extended battery life, enabling users to make calls throughout the day without frequent recharging. Its lightweight design and ergonomic build make it comfortable to use for extended periods.

In terms of integration, the Cisco 7920 IP phone is compatible with various Cisco Unified Communications Manager software versions, allowing for easy configuration and management within existing network infrastructures. Its support for multiple languages also makes it a suitable choice for international organizations, accommodating diverse user groups.

Overall, the Cisco Systems 7920 IP phone combines the necessary features, technologies, and characteristics to meet the demands of modern enterprise communication. Its blend of wireless capability, superior audio quality, security measures, and integration versatility makes it an excellent choice for organizations seeking efficient and reliable communication solutions.
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