Cisco Systems 7920 IP manual Caveats and Limitations

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∙Cisco Emergency Responder can query for IP Phones through either CDP (on the Catalyst switches) or the MAC address. Since CDP is sent as a link−layer multicast and is used by the Cisco AP to determine the QoS settings for the Cisco 7920, it is not propagated up to the Catalyst switch. This means that Cisco Emergency Responder should query the Catalyst switches for the MAC addresses of the Cisco 7920 phones.

∙Cisco Emergency Responder groups devices into Emergency Response Locations (ERL) so they can be identified by a physical location (such as building, floor, or region of floor). Depending on how the power levels are configured on the Cisco APs, it is possible that the signal could propagate to floors above or below the actual AP that the Cisco 7920 is associated with. Using antennas that propagate RF signal in a more horizontal pattern helps alleviate this, but emergency personnel within a building should be made aware of this when organizing their searches for the individual or device that initiated the emergency call.

An E911 coverage policy is an individual decision that each company needs to make and adapt it to their physical locations.

It is recommended that each AP been assigned to its own ERL (or minimally grouping a couple of adjacent APs into one ERL). This has the benefit of allowing on−site, and potentially PSAP personnel, to identify that the caller is using a wireless device (by using a code or abbreviation in the Automatic Location Information (ALI) or switch port location field). This is important information for first responders because it means that adjacent floors, hallways, rooms, and even buildings may need to be searched to locate an unconscious or incapable caller. The following image is an example of the Cisco Emergency Responder's configuration Graphical User Interface (GUI):

Caveats and Limitations

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

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Contents Table of Contents Prerequisites IntroductionRequirements RF Overview Site Surveys and Design Recommendations Cisco 7920 IP Phone OverviewWlan Overview Components UsedVoIP QoS Rssi∙ 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 Layer 2 and Layer 3 Roaming Understanding Roaming TerminologyLayer 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 EI Connecting APs to the Catalyst 2950 SICaveats 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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