Cisco Systems 7920 IP manual ∙ Delay Variation Jitter Not to exceed 30ms

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Voice traffic can be classified with the following characteristics:

∙Smooth ￿ VoIP packets are sent at consistent intervals with uniform packet sizes.

∙Benign ￿ VoIP packets only attempt to use the bandwidth necessary to send from end to end. VoIP does not use any windowing to determine data rates.

∙Packet Loss Sensitive ￿ VoIP traffic is extremely sensitive to packet loss. Excessive loss degrades overall voice quality.

∙Delay Sensitive ￿ While VoIP can tolerate some amount of delay, excessive delay or excessive delay variation (jitter) degrade overall voice quality.

∙User Datagram Protocol (UDP) Best Effort ￿ VoIP sends Real Time Protocol (RTP) packets using UDP. UDP does not have a mechanism to retransmit lost packets.

The network guidelines defined by Cisco AVVID for proper VoIP operation are as follows:

∙Delay ￿ Not to exceed 150 ms (one way).

∙Delay Variation (Jitter) ￿ Not to exceed 30ms.

∙Packet Loss ￿ Not to exceed 1 percent.

Note: While isolated testing may show that VoIP calls could operate in a network outside of these guidelines, deploying a VoIP network under those conditions cannot be predictably engineered. Support from the Cisco

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

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Contents Table of Contents Requirements IntroductionPrerequisites Wlan Overview Cisco 7920 IP Phone OverviewRF Overview Site Surveys and Design Recommendations Components UsedRssi VoIP QoS∙ Delay Variation Jitter Not to exceed 30ms Security for the Cisco 7920 and Wlan Networks Number of 802.11b IP Phones per AP Network SizingNumber of 802.11b Devices 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 Other Caveats and Limitations Call Admission ControlDesigning Around the Lack of Layer 3 Roaming 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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