Cisco Unified IP Phone 7931G Administration Guide for Cisco Unified Communications Manager 9.0 (SCCP and SIP)
Cisco Unified IP Phones and Telephony Networks
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Cisco Unified IP Phones and Telephony Networks

Contents

Cisco Unified IP Phones and Telephony Networks

Phone and Telephony Network Overview

Cisco Unified IP Phones enable you to communicate using voice over a data network. To provide this capability, the phones depend upon and interact with several other key Cisco IP Telephony and network components, including Cisco Unified Communications Manager, Domain Name System (DNS) and DHCP servers, TFTP servers, media resources, and Cisco PoE.

This chapter focuses on the interactions between the Cisco Unified IP Phone 7931G and Cisco Unified Communications Manager, DNS and DHCP servers, TFTP servers, and switches. It also describes options for powering phones.

For related information about voice and IP communications, refer to this URL (you must be a registered Cisco.com user):

http:/​/​www.cisco.com/​en/​US/​products/​sw/​voicesw/​index.html

Cisco Unified IP Communications Product Interactions

To function in the IP telephony network, the Cisco Unified IP Phone must be connected to a networking device, such as a Cisco Catalyst switch. You must also register the Cisco Unified IP Phone with a Cisco Unified Communications Manager system before sending and receiving calls.

Cisco Unified IP Phone and Cisco Unified Communications Manager Interaction

Cisco Unified Communications Manager is an open and industry-standard call processing system. Cisco Unified Communications Manager software sets up and tears down calls between phones, integrating traditional PBX functionality with the corporate IP network. Cisco Unified Communications Manager manages the components of the IP telephony system: the phones, the access gateways, and the resources necessary for features such as call conferencing and route planning. Cisco Unified Communications Manager also provides:

  • Firmware for phones
  • Authentication and encryption (if configured for the telephony system)
  • Configuration, certificate trust list (CTL), and Identity Trust List (ITL) files via the TFTP service
  • Phone registration
  • Call preservation, so that a media session continues if signaling is lost between the primary Communications Manager and a phone

For information about configuring Cisco Unified Communications Manager to work with the IP devices described in this chapter, see Cisco Unified Communications Manager Administration Guide, Cisco Unified Communications Manager System Guide, and Cisco Unified Communications Manager Security Guide.

For an overview of security functionality for the Cisco Unified IP Phone, see the Cisco Unified IP Phone Security Features.


Note


If the Cisco Unified IP Phone model that you want to configure does not appear in the Phone Type drop-down list in Cisco Unified Communications Manager Administration, go to the following URL and install the latest support patch for your version of Cisco Unified Communications Manager: http:/​/​www.cisco.com/​kobayashi/​sw-center/​sw-voice.shtml


Cisco Unified IP Phone and VLAN Interaction

The Cisco Unified IP Phone 7931G has an internal Ethernet switch, enabling forwarding of packets to the phone, and to the access port and the network port on the back of the phone.

If a computer is connected to the access port, the computer and the phone share the same physical link to the switch and the same switch port. This shared physical link has these implications for the network VLAN configuration:

  • Although the current VLANs may be configured on an IP subnet basis, additional IP addresses may not be available to assign the phone to the same subnet as other devices that connect to the same port.
  • Data traffic present on the data/native VLAN may reduce the quality of VoIP traffic.
  • Network security may need to isolate the VLAN voice traffic from the VLAN data traffic.

You can resolve these issues by isolating the voice traffic onto a separate VLAN. The switch port that the phone is connected to would be configured to have separate VLANs for carrying:

  • Voice traffic to and from the phone (auxiliary VLAN, on the Cisco Catalyst 6000 series, for example)
  • Data traffic to and from the PC connected to the switch through the access port of the IP phone (native VLAN)

Isolating the phones on a separate, auxiliary VLAN improves the quality of the voice traffic and allows a large number of phones to be added to an existing network where there are not enough IP addresses for each phone.

For more information, refer to the documentation included with a Cisco switch. You can also access related documentation at this URL:

http:/​/​cisco.com/​en/​US/​products/​hw/​switches/​index.html

Related Tasks
Related References

Cisco Unified IP Phone Power

The Cisco Unified IP Phone 7931G can be powered with external power or with Power over Ethernet (PoE). External power is provided through a separate power supply. PoE is provided by a switch through the Ethernet cable attached to a phone.

Power Outage

Your access to emergency service through the phone requires the phone to receive power. If an interruption in the power supply occurs, Service and Emergency Calling Service dialing do not function until power is restored. In the case of a power failure or disruption, you may need to reset or reconfigure equipment before you can use the Service or Emergency Calling Service dialing.

Power Guidelines

The following table provides guidelines that apply to external power and to PoE power for the Cisco Unified IP Phone 7931G.

Table 1 Guidelines for Cisco Unified IP Phone 7931G Power

Power Type

Guidelines

External power: Provided through a Cisco external power supply.

The CP-PWR-CUBE-3 external power supply may be used with the Cisco Unified IP Phone 7931G.

External power: Provided through the Cisco Unified IP Phone Power Injector.

The Cisco Unified IP Phone Power Injector may be used with any Cisco Unified IP Phone. Functioning as a midspan device, the injector delivers inline power to the attached phone. The Cisco Unified IP Phone Power Injector is connected between a switch port and the IP Phone, and supports a maximum cable length of 100m between the unpowered switch and the phone.

PoE power: Provided by a switch through the Ethernet cable attached to the phone.

  • The Cisco Unified IP Phone 7931G supports IEEE 802.3af Power over Ethernet.
  • To ensure uninterruptible operation of the phone, make sure that the switch has a backup power supply.
  • Make sure that the CatOS or IOS version running on your switch supports your intended phone deployment. Refer to the documentation for your switch for operating system version information.

Additional Information About Power

For related information about power, refer to these documents:

Phone Configuration Files

Phone configuration files are stored on the TFTP server and define Cisco Unified Communications Manager connection parameters. In general, whenever you make a change in Cisco Unified Communications Manager that requires the phone to reset, a change is made automatically to the phone configuration file.

Configuration files also contain information about the image load that the phone should be running. If this image load differs from the one currently that is loaded on a phone currently, the phone contacts the TFTP server to request the required load files. These load files are digitally signed to ensure the authenticity of the file source.

In addition, if the device security mode in the configuration file is set to Authenticated and the CTL file on the phone has a valid certificate for Cisco Unified Communications Manager, the phone establishes a TLS connection to Cisco Unified Communications Manager. Otherwise, the phone establishes a TCP connection. For SIP phones, a TLS connection requires that the transport protocol in the phone configuration file be set to TLS, which corresponds to the transport type in the SIP Security Profile in Cisco Unified Communications Manager Administration.


Note


If the device security mode in the configuration file is set to Authenticated or Encrypted but the phone has not received a CTL or ITL file, the phone tries four times to obtain the file so it can register securely.



Note


Cisco Extension Mobility Cross Cluster is an exception, in that the phone permits a TLS connection to Cisco Unified Communications Manager for secure signaling even without the CTL file.


If you configure security-related settings in Cisco Unified Communications Manager Administration, the phone configuration file contains sensitive information. To ensure the privacy of a configuration file, you must configure it for encryption. For more information, see the Cisco Unified Communications Manager Security Guide, "Configuring Encrypted Phone Configuration Files" chapter.

A phone requests a configuration file whenever it resets and registers with Cisco Unified Communications Manager.

A phone accesses a default configuration file named XmlDefault.cnf.xml only when the phone has not received a valid Trust List file that contains a certificate assigned to Cisco Unified Communications Manager and TFTP.

If autoregistration is not enabled and you did not add the phone to the Cisco Unified Communications Manager database, the phone system rejects the phone registration request with Cisco Unified Communications Manager. The phone displays the Configuring IP message continuously until you either enable autoregistration or add the phone to the Cisco Unified Communications Manager database.

If the phone has registered previously, the phone accesses the configuration file named SEPmac_address.cnf.xml, where mac_address is the MAC address of the phone.

For SIP phones, the TFTP server generates these SIP configuration files:

  • SIP IP Phone
    • For unsigned and unencrypted files: SEP<mac>.cnf.xml
    • For signed files: SEP<mac>.cnf.xml.sgn
    • For signed and encrypted files: SEP<mac>.cnf.xml.enc.sgn
  • Dial Plan: <dialplan>.xml
  • Softkey Template: <softkey_template>.xml

The filenames derive from the MAC Address and Description fields in the Phone Configuration window of Cisco Unified Communications Manager. The MAC address uniquely identifies the phone. For more information, see the Cisco Unified Communications Manager Administration Guide.

For more information about the phone interaction with the TFTP server, see the Cisco Unified Communications Manager System Guide, "Cisco TFTP" chapter.

Phone Startup Process

When connecting to the VoIP network, the Cisco Unified IP Phone goes through a standard startup process, as described in the following table. Depending on your network configuration, not all of these process steps may occur on your Cisco Unified IP Phone.

Procedure
    Step 1   Obtaining Power from the Switch.

    If a phone is not using external power, the switch provides in-line power through the Ethernet cable that is attached to the phone.

    Step 2   Loading the Stored Phone Image.

    Cisco Unified IP Phones have non-volatile flash memory in which the phone stores firmware images and user-defined preferences. At startup, the phone runs a bootstrap loader that loads a phone image stored in flash memory. Using this image, the phone initializes its software and hardware.

    Step 3   Configuring VLAN.

    If the Cisco Unified IP Phone is connected to a Cisco switch, the switch next informs the phone of the voice VLAN defined on the switch port. The phone needs to know its VLAN membership before it can proceed with the DHCP request for an IP address.

    Step 4   Obtaining an IP Address.

    If the Cisco Unified IP Phone is using DHCP to obtain an IP address, the phone queries the DHCP server to obtain one. If your network does not use DHCP, you must assign static IP addresses to each phone locally.

    Step 5   Accessing a TFTP Server.

    In addition to assigning an IP address, the DHCP server directs the Cisco Unified IP Phone to a TFTP Server. If the phone has a statically defined IP address, you must configure the TFTP server locally on the phone; the phone then contacts the TFTP server directly.

    Note   

    You can also assign an alternative TFTP server to use instead of the one assigned by DHCP.

    Step 6   Requesting the CTL file.

    The TFTP server stores the CTL file. This file also contains the certificates necessary for establishing a secure connection between the phone and Cisco Unified Communications Manager.

    For more information, see the Cisco Unified Communications Manager Security Guide, “Configuring the Cisco CTL Client” chapter.

    Step 7   Requesting the ITL file.

    The phone requests the ITL file after it requests the CTL file. The ITL file contains the certificates of the entities that the phone can trust. The certificates are used for authenticating a secure connection with the servers or authenticating a digital signature signed by the servers. The ITL file is available to the phone only on Cisco Unified Communications Manager 8.0 and later.

    For more information, see the Cisco Unified Communications Manager Security Guide, “Security by Default” chapter.

    Step 8   Requesting the Configuration file.

    The TFTP server has configuration files, which define parameters for connecting to Cisco Unified Communications Manager and other information for the phone.

    Step 9   Contacting Cisco Unified Communications Manager.

    The configuration file defines how the Cisco Unified IP Phone communicates with Cisco Unified Communications Manager and provides a phone with its load ID. After obtaining the file from the TFTP server, the phone attempts to make a connection to the highest priority Cisco Unified Communications Manager on the list. When the security profile of the phone is configured for secure signaling (encrypted or authenticated) and the Cisco Unified Communications Manager is set to secure mode, the phone makes a TLS connection. Otherwise, it makes a nonsecure TCP connection.

    If the phone was manually added to the database, Cisco Unified Communications Manager identifies the phone. If the phone was not added manually to the database and auto-registration is enabled in Cisco Unified Communications Manager, the phone attempts to autoregister itself in the Cisco Unified Communications Manager database.

    Note   

    Auto-registration is disabled when security is enabled on Cisco Unified Communications Manager. In this case, the phone must be manually added to the Cisco Unified Communications Manager database.


    Related References

    Cisco Unified Communications Manager Phone Addition Methods

    Before installing the Cisco Unified IP Phone, you must choose a method for adding phones to the Cisco Unified Communications Manager database.

    The following table provides an overview of these methods for adding phones to the Cisco Unified Communications Manager database.

    Table 2 Methods for Adding Phones to the Cisco Unified Communications Manager Database

    Method

    Requires MAC Address?

    Notes

    Autoregistration

    No

    Results in automatic assignment of directory numbers.

    Not available when security or encryption is enabled.

    Autoregistration with TAPS

    No

    Requires autoregistration and the Bulk Administration Tool (BAT); updates the Cisco Unified Communications Manager database with the MAC address and DNs for the device when user calls TAPS from the phone.

    Using Cisco Unified Communications Manager Administration

    Yes

    Requires phones to be added individually.

    Using BAT

    Yes

    Can add groups of same model of phone.

    Can schedule when phones are added to the Cisco Unified Communications Manager database.

    Related Tasks

    Autoregistration Phone Addition

    If you enable autoregistration before you begin installing phones, you can:

    • Add phones without first gathering MAC addresses from the phones.
    • Automatically add a Cisco Unified IP Phone to the Cisco Unified CM database when you physically connect the phone to your IP telephony network. During autoregistration, Cisco Unified Communications Manager assigns the next available sequential directory number to the phone.
    • Quickly enter phones into the Cisco Unified Communications Manager database and modify any settings, such as the directory numbers, from Cisco Unified Communications Manager.
    • Move autoregistered phones to new locations and assign them to different device pools without affecting their directory numbers.

    Note


    Cisco recommends that you use autoregistration to add fewer than 100 phones to your network. To add more than 100 phones to your network, use the Bulk Administration Tool (BAT).


    Autoregistration is disabled by default. In some cases, you might not want to use autoregistration; for example, if you want to assign a specific directory number to the phone. For information about enabling autoregistration, see "Enable autoregistration" section in the Cisco Unified Communications Manager Administration Guide.


    Note


    When you configure the cluster for mixed mode through the Cisco CTL client, autoregistration is automatically disabled. When you configure the cluster for nonsecure mode through the Cisco CTL client, autoregistration is automatically enabled.


    Autoregistration and TAPS Phone Addition

    You can add phones with autoregistration and TAPS, the Tool for Auto-Registered Phones Support, without first gathering MAC addresses from phones.

    TAPS works with the Bulk Administration Tool (BAT) to update a batch of phones that were already added to the Cisco Unified Communications Manager database with dummy MAC addresses. Use TAPS to update MAC addresses and download predefined configurations for phones.


    Note


    Cisco recommends that you use autoregistration and TAPS to add less than 100 phones to your network. To add more than 100 phones to your network, use the Bulk Administration Tool (BAT).


    To implement TAPS, dial a TAPS directory number and follow the voice prompts. When the process completes, the phone has downloaded the directory number and other settings, and the phone is updated in Cisco Unified Communications Manager Administration with the correct MAC address.

    Autoregistration must be enabled in Cisco Unified Communications Manager Administration (System > Cisco Unified CM) for TAPS to function.


    Note


    When you configure the cluster for mixed mode through the Cisco CTL client, autoregistration is automatically disabled. When you configure the cluster for nonsecure mode through the Cisco CTL client, autoregistration is automatically enabled.


    For more information, see "Bulk Administration" chapter in the Cisco Unified Communications Manager Administration Guide and the "Tool for Auto-Registered Phones Support" chapter in the Cisco Unified Communications Manager Bulk Administration Guide.

    Cisco Unified Communications Manager Administration Phone Addition

    You can add phones individually to the Cisco Unified Communications Manager database using Cisco Unified Communications Manager Administration. To do so, you first need to obtain the MAC address for each phone.

    After you have collected MAC addresses, in Cisco Unified Communications Manager Administration, choose DevicePhone and click Add New to begin.

    For complete instructions and conceptual information about Cisco Unified Communications Manager, refer to Cisco Unified Communications Manager Administration Guide and to Cisco Unified Communications Manager System Guide.

    Add Phones with BAT

    The Cisco Unified Communications Bulk Administration Tool (BAT), which is a menu option in Cisco Unified Communications Manager Administration, enables you to perform batch operations, which includes registration, on multiple phones.

    Before you can add phones using BAT only (not in conjunction with TAPS), you must obtain the MAC address for each phone.

    To add a phone to the Cisco Unified Communications Manager, follow these steps:

    Procedure
      Step 1   From Cisco Unified Communications Manager, choose Bulk Administration > Phones > Phone Template.
      Step 2   Click Add New.
      Step 3   Choose a Phone Type and click Next.
      Step 4   Enter the details of phone specific parameters such as Device Pool, Phone Button Template, and Device Security Profile.
      Step 5   Click Save.
      Step 6   From Cisco Unified Communications Manager, choose Device > Phone > Add New to add a phone using an already created BAT phone template.

      For detailed instructions about using BAT and BAT phone templates, see the Cisco Unified Communications Manager Bulk Administration Guide, “Phone Template” chapter.


      Cisco Unified IP Phones and Different Protocols

      The Cisco Unified IP Phones can operate with Skinny Client Control Protocol (SCCP) or Session Initiation Protocol (SIP). You can convert a phone from using one protocol to using the other protocol.

      Convert New Phone from SCCP to SIP

      A new, unused phone is set for SCCP by default. To convert this phone to SIP, perform these steps:

      Procedure
        Step 1   Take one of these actions:
        1. To autoregister the phone, set the Auto Registration Phone Protocol enterprise parameter in Cisco Unified Communications Manager Administration to SIP.
        2. To provision the phone by using the Bulk Administration Tool (BAT), choose the appropriate phone model and choose SIP from BAT.
        3. To provision the phone manually, make the appropriate changes for SIP on the Phone Configuration window in Cisco Unified Communications Manager Administration.

          For detailed information about the Cisco Unified Communications Manager configuration, see the Cisco Unified Communications Manager Administration Guide. Refer to Cisco Unified Communications Manager Bulk Administration Guide for detailed information about using the BAT.

        Step 2   If you are not using DHCP in your network, configure the network parameters for the phone.
        Step 3   To save the configuration updates, click Apply Config, click OK when the Apply Configuration Information dialog displays, then have the user power cycle the phone.

        Related Information

        In-Use Phone Protocol to Protocol Conversion

        For information on how to convert an in-use phone from one protocol to the other, see the Cisco Unified Communications Manager Administration Guide, "Cisco Unified IP Phone Configuration" chapter, "Migrate existing phone settings to another phone" section.

        Deploy Phone in SCCP and SIP Environment

        To deploy Cisco Unified IP Phones in an environment that includes SCCP and SIP and in which the Cisco Unified Communications Manager autoregistration parameter specifies SCCP, perform these general steps:

        Procedure
          Step 1   Set the Cisco Unified Communications Manager auto_registration_protocol parameter to SCCP.
          Step 2   From Cisco Unified Communications Manager, choose System > Enterprise Parameters.
          Step 3   Install the phones.
          Step 4   Change the Auto Registration Protocol enterprise parameter to SIP.
          Step 5   Autoregister the SIP phones.

          Cisco Unified IP Phone MAC Address Determination

          Several of the procedures that are described in this manual require you to determine the MAC address of Cisco Unified IP Phones. You can determine the MAC address for a phone in any of these ways:

          • If the phone is registered with Cisco Unified Communications Manager, press the Application Menu button, choose Settings > Model Information and look at the MAC Address field. By default, the Application Menu button is line button 24 (the top left line button).
          • If the phone is not registered with Cisco Unified Communications Manager, press the Settings softkey, choose Model Information and look at the MAC Address field.

          This softkey appears only when the phone is not registered.

          • Look at the MAC label on the back of the phone.
          • Display the web page for the phone and click the Device Information hyperlink.