Chapter 9 Troubleshooting and Maintenance

Cisco Unified IP Phone Resets Unexpectedly

Checking Static IP Address Settings

If the phone has been assigned a static IP address, verify that you have entered the correct settings. See the “Network Configuration Menu” section on page 4-7for more information.

Verifying Voice VLAN Configuration

If the Cisco Unified IP Phone appears to reset during heavy network usage (for example, following extensive web surfing on a computer connected to same switch as phone), it is likely that you do not have a voice VLAN configured. Isolating the phones on a separate auxiliary VLAN increases the quality of the voice traffic.

Verifying that the Phones Have Not Been Intentionally Reset

If you are not the only administrator with access to Cisco Unified CallManager, you should verify that no one else has intentionally reset the phones.

You can check whether a Cisco Unified IP Phone received a command from Cisco Unified CallManager to reset by pressing the Applications Menu button on the phone and choosing Settings > Status > Network Statistics. If the phone was recently reset one of these messages appears:

Reset-Reset—Phone closed due to receiving a Reset/Reset from Cisco Unified CallManager administration.

Reset-Restart—Phone closed due to receiving a Reset/Restart from Cisco Unified CallManager administration.

 

Cisco Unified IP Phone 7906G and 7911G Administration Guide for Cisco Unified CallManager

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Cisco Systems 7906G, 7911G manual Checking Static IP Address Settings, Verifying Voice Vlan Configuration

7906G, 7911G specifications

The Cisco Systems 7911G is a versatile IP phone designed to enhance communication in enterprise environments. Targeting workers in various organizational settings, this model is known for its reliability, ease of use, and robust features that cater to both basic and advanced telephony requirements.

One of the key features of the Cisco 7911G is its support for Voice over IP (VoIP) technology. Using this technology allows for the transmission of voice signals over the internet rather than through traditional telephone lines. This not only reduces telephony costs but also offers enhanced functionality that integrates seamlessly with existing communication systems.

The phone is equipped with a monochrome graphical display that provides users with clear visibility of their call status, directory information, and menu options. With a resolution of 128x64 pixels, the screen is large enough to offer important information without overwhelming the user. This simplicity makes it an ideal choice for users who require straightforward functionality without the complexity of advanced features.

Ergonomically designed, the Cisco 7911G features a comfortable keypad with dedicated buttons for frequently used functions such as mute, hold, and transfer. It supports multiple lines, providing users with the ability to manage multiple calls simultaneously. Additionally, it offers programmable line keys that can be customized for speed dial or as soft keys for quick access to features.

The device supports Power over Ethernet (PoE), which allows the phone to receive power through the network cable rather than needing a separate power source. This feature not only simplifies installation but also enhances mobility within the workspace, as it reduces cable clutter.

Another significant characteristic of the Cisco 7911G is its compatibility with Cisco Unified Communications Manager, which ensures centralized management of telephony systems. It also supports a range of audio codecs that help in delivering high-quality audio during calls, reducing latency and improving overall communication quality.

Security is also a focus with the Cisco 7911G, as it features a secure access feature that includes Transport Layer Security (TLS) and Secure Real-Time Transport Protocol (SRTP) for encrypted voice communications. This ensures that sensitive conversations are protected from eavesdropping.

Overall, the Cisco Systems 7911G is a reliable, feature-rich IP phone that provides an excellent solution for organizations looking to upgrade their communication systems. Its combination of user-friendly design, powerful integrations, and security features makes it a cornerstone in the suite of Cisco telecommunications solutions.