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Cisco Unified Communications Manager (CallManager)

Configuring an Anonymous Device Gatekeeper with Cisco CallManager Versions 3.3 and 4.1

Cisco - Configuring an Anonymous Device Gatekeeper with Cisco CallManager Versions 3.3 and 4.1

Document ID: 42063

Updated: Jan 20, 2006

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Introduction

This document explains how to set up an anonymous device gatekeeper with use of a Cisco CallManager 4.1 or 3.3 server. It requires the use of a Cisco IOS® Software router to act as a gatekeeper and a Cisco IOS router to act as an H.323 gateway. The primary focus of this document is on how to configure the Cisco CallManager 4.1 or 3.3 server to use a gatekeeper. After you finish this configuration, you can make calls in either direction with Call Admission Control (CAC) between an IP phone registered to the Cisco CallManager 4.1 or 3.3 server and an analog phone attached to the Cisco IOS gateway.

Prerequisites

Requirements

Before you attempt this configuration, ensure that you meet these requirements:

  • You have a sample network with a Cisco CallManager server.

  • You have an IP phone (model 7910, 7940, or 7960).

  • You have a Cisco IOS gateway with an Foreign Exchange Station (FXS) port.

  • You have an analog phone that is attached to the FXS port on the Cisco IOS gateway.

  • You have a Cisco IOS router with an image that supports H.323 gatekeeper functionality.

  • All devices can ping each other.

  • The IP phone can call the analog phone with two-way voice capability.

  • The analog phone can call the IP phone with two-way voice capability.

Note: For more information, see the Network Diagram in this document.

Components Used

The information in this document is based on these software and hardware versions:

  • Cisco IOS router that acts as an H.323 VoIP gateway and runs Cisco IOS Software Release 12.2(11)T

  • Cisco IOS router that acts as an H.323 VoIP gatekeeper and runs Cisco IOS Software Release 12.2(15)T

  • Cisco CallManager server that runs 4.1(.091) or 3.3(3)sr4a

  • 7960 IP Phone

  • Generic analog phone

The information in this document was created from the devices in a specific lab environment. All of the devices used in this document started with a cleared (default) configuration. If your network is live, make sure that you understand the potential impact of any command.

Conventions

For more information on document conventions, refer to the Cisco Technical Tips Conventions.

Background Theory

An anonymous device gatekeeper handles call-route decisions for the Cisco IOS gateways and Cisco CallManager gateways that are registered to it. This means that the Cisco CallManager servers in the cluster do not need to know about every other gateway in the network. Instead, their route patterns or VoIP dial peers are configured to point to the anonymous device gatekeeper. The anonymous device gatekeeper keeps track of the dial plan for the network. Refer to the document Understanding Cisco IOS Gatekeeper Call Routing for additional information on this subject.

Networks used to learn internetwork skills typically use the configuration presented in this document. The concepts and commands are the same ones that you encounter in a live environment. The primary difference is that this scenario does not have a WAN connection for VoIP traffic that benefits from CAC.

Note: In Cisco CallManager 4.1 and 3.3, trunks replace all previously configured intercluster trunk devices. An H.225 trunk device represents a logical route to the wholesale network. Previously configured anonymous devices with H.225 protocol migrate to H.225 trunks with gatekeeper control. Previously configured anonymous devices with intercluster protocol migrate to intercluster trunks with gatekeeper control. Previously configured intercluster gateways migrate to intercluster trunks without gatekeeper control.

The successful implementation of CAC requires a well thought-out network design and CAC overlay that corresponds to it. A complete explanation of how to design and implement a CAC solution—which includes all of the available options to implement CAC on Cisco IOS gateways and gatekeepers—is beyond the scope of this document. There are several good resources available on Cisco.com to help you understand and implement CAC with Cisco IOS Software-based gateways and gatekeepers. Search for gatekeeper on Cisco.com. You can then filter your search with additional words, such as troubleshooting or understanding. You can also limit the scope of your search to Products and Services or Technical Support (content written by Technical Support only).

Network Diagram

This document uses this network setup:

ccma_with_gk1.gif

Configure the Cisco CallManager Gatekeeper Parameters

This section explains how to create an instance of an anonymous device gatekeeper in Cisco CallManager.

Step-by-Step Instructions

  1. Choose Device > Gatekeeper.

    The Find and List Gatekeeper Configuration window displays.

  2. In the upper, right corner of the window, click the Add a New Gatekeeper link.

    The Gatekeeper Configuration window displays.

    Note: If a gatekeeper already exists, you may want to delete it and start over. This ensures that you start with the default values for any parameters that this section does not specifically mention.

  3. Enter these parameters:

    Parameter Setting
    Host Name/IP Address Enter the IP address or host name of the gatekeeper in this required field. You can register multiple gatekeepers for each Cisco CallManager cluster. In this case, it is 10.89.129.228.
    Description Enter a descriptive name for the gatekeeper. In this case, it is psy-gk-01.
    Enable Device Ensure that the check box for this field is checked. This allows you to register this gatekeeper with Cisco CallManager. By default, this check box remains checked.

    The parameter page appears as shown:

    ccma_with_gk2.gif

  4. Click Insert or Update, as indicated.

Configure the H.225 Trunk Parameters

This section explains how to configure an H.225 trunk device that represents a logical route to the wholesale network.

Step-by-Step Instructions

  1. Choose Device > Trunk.

  2. Choose Add a New Trunk.

  3. In the Trunk type field, click the drop-down arrow and choose H.225 Trunk (Gatekeeper Controlled).

  4. In the Device Protocol field, click the drop-down arrow and choose H.225, as shown here:

    ccma_with_gk3.gif

  5. For Cisco CallManager 4.1, complete these steps.

    Note: For Cisco CallManager 3.3, move on to Step 6.

    1. Leave the other fields set to their defaults, and click Next.

      The Trunk Configuration window appears.

    2. Enter these parameters:

      Parameter Setting
      Device Name Enter a unique identifier for the trunk. In this case, it is h225_trk.
      Description Enter a descriptive name for the trunk.
      Device Pool Choose the appropriate device pool for the trunk. In this case, it is Default.
      Gatekeeper Name Choose the gatekeeper IP address that controls this trunk. In this case, it is 10.89.129.228.
      Terminal Type Choose Gateway.
      Technology Prefix Enter 1#* in this field.
      Zone Enter the appropriate zone. In this case, the zone used is horse.

      The parameter page appears as shown:

      ccma_with_gk4.gif

    3. Skip Step 6 and move on to Step 7.

  6. For Cisco CallManager 3.3, enter the parameters listed in this table.

    Note: The only difference between Cisco CallManager 4.x and 3.3 in this regard is the addition of the parameters Calling Party Selection and Calling Line ID Presentation.

    Parameter Setting
    Device Name Enter a unique identifier for the trunk. In this case, it is h225_trk.
    Description Enter a descriptive name for the trunk.
    Device Pool Choose the appropriate device pool for the trunk. In this case, it is Default.
    Calling Party Selection Choose Originator.
    Calling Line ID Presentation Choose Default.
    Gatekeeper Name Choose the gatekeeper IP address that controls this trunk. In this case, it is 10.89.129.228.
    Terminal Type Choose Gateway.
    Technology Prefix Enter 1#* in this field.
    Zone Enter the appropriate zone. In this case, the zone used is horse.

  7. Click Update, and click Reset Trunk.

Change the Route Pattern to Use the Cisco CallManager Gatekeeper

This section explains how to point a route pattern at a gatekeeper (which, in this case, is the anonymous device gatekeeper) rather than at a gateway or route list.

Step-by-Step Instructions

  1. Choose Route Plan > Route/Hunt > Route Pattern.

  2. Click Find.

  3. Click the Route Pattern that you have configured to route calls to the analog phone.

    In this case, it is the route pattern for extension 2000.

  4. In the Gateway/Route List field, click the drop-down arrow and choose h225_trk.

    This is the trunk you just created.

    Note: If your previous configuration allowed calls from your IP phone to your analog phone (as mentioned in the Requirements section of this document), you should not need to make any further changes. Set the remainder of the parameters for the route pattern, as shown in this window, to values that are known to work for the scenario of this document:

    ccma_with_gk5.gif

  5. Click Update.

Configure the Gatekeeper Parameters

This section explains how to configure the Cisco IOS gatekeeper parameters required for CAC.

Use this configuration for the Cisco gatekeeper:

!
!
gatekeeper
 zone local horse maui-onions.com 10.89.129.228
 zone prefix horse 2* gw-priority 10 10.89.129.211
 zone prefix horse 2* gw-priority 0 10.89.129.226
 gw-type-prefix 1#* default-technology
 bandwidth total zone horse 256
 no shutdown
!
!

Notes for This Configuration

  • The gatekeeper controls the zone named horse. This is why it is configured as a local zone. The IP address is a local address that is used as the source address for CAC IP packets from the gatekeeper.

  • The zone prefix commands for the horse zone are the dial plan for this zone. This is how the gatekeeper associates dialed numbers with the correct zone.

    A priority of 1 or higher indicates that a gateway is a viable path to route calls to the prefix configured. A priority of 0 indicates that a gateway is not a viable path to route calls to the prefix configured.

    A complete explanation of how gatekeepers make route decisions is beyond the scope of this document. Refer to the document Understanding Cisco IOS Gatekeeper Call Routing for more information on how gatekeepers make call-route decisions.

  • In this scenario, you do not prepend technology prefixes to the dialed digits when the calls are routed to the gatekeeper. This is why the gatekeeper requires the gw-type-prefix 1#* default-technology command and the Cisco IOS gateway requires the h323-gateway voip tech-prefix 1# command as well as the Technology Prefix 1#* parameter on the Cisco CallManager gatekeeper configuration. If you neglect to meet these configuration requirements, calls do not complete successfully.

  • This zone has a total bandwidth capacity of 256 kbps.

    Note: There are two versions of the command to set the bandwidth for a zone, which depends on the version of Cisco IOS Software you run on the gatekeeper. The command versions are bandwidth total zone and zone bw.

Configure the Gateway Parameters

This section explains how to configure the Cisco IOS gateway parameters required for CAC.

Use this configuration for the Cisco gateway:

!
interface Ethernet0/0
 ip address 10.89.129.226 255.255.255.240
 full-duplex
 h323-gateway voip interface
 h323-gateway voip id horse ipaddr 10.89.129.228 1719
 h323-gateway voip h323-id psy-voice-01@maui-onions.com
 h323-gateway voip tech-prefix 1#
 h323-gateway voip bind srcaddr 10.89.129.226
!
voice-port 1/0/0
!
voice-port 1/0/1
!
dial-peer voice 1 pots
 destination-pattern 2000
 port 1/0/1
!
dial-peer voice 2 voip
 destination-pattern 1...
 session target ras
!
gateway
!

Notes for This Configuration

  • In this scenario, you do not prepend technology prefixes to the dialed digits when the calls are routed to the gatekeeper. This is why the Cisco IOS gateway requires the command h323-gateway voip tech-prefix 1# and the gatekeeper requires the command gw-type-prefix 1#* default-technology as well as the Technology Prefix 1#* parameter on the Cisco CallManager gatekeeper configuration. If you neglect to meet these configuration requirements, calls do not complete successfully.

  • You must include the gateway command. The other parameters that you can apply under the gateway command are optional.

  • The session target ras command on the gateway causes it to route calls to 1006 (the Directory Number [DN] of the IP phone) to the gatekeeper with the destination-pattern 1... wildcard.

  • The h323-gateway voip h323-id command provides a unique identifier for this gateway that appears in the show gatekeeper endpoints command on the gatekeeper.

  • The voice port 1/0 in the Cisco IOS gateway is an FXS port. The destination pattern (2000) under POTS dial peer registers as an E.164 (ITU-T) ID with the gatekeeper. You can see this in the output of the show gatekeeper endpoints command on the gatekeeper.

Verify

This section provides some of the basic commands available to verify that your gatekeeper configuration works properly. There are several other documents on Cisco.com that explain how to verify and troubleshoot gatekeeper configurations in greater detail. See the Related Information

Related Cisco Support Community Discussions section of this document for more information.

Note: Certain show commands are supported by the Output Interpreter Tool (registered customers only) , which allows you to view an analysis of show command output.

Use the show gatekeeper endpoints Command

Use the show gatekeeper endpoints command on the gatekeeper to verify that the two gateways (Cisco CallManager server and the Cisco IOS gateway router) have registered.

psy-gk-01# show gatekeeper endpoints
                    GATEKEEPER ENDPOINT REGISTRATION
                    ================================
CallSignalAddr  Port  RASSignalAddr   Port  Zone Name         Type    Flags
--------------- ----- --------------- ----- ---------         ----    -----
10.89.129.211   3152  10.89.129.211   1494  horse             VOIP-GW
    H323-ID: h225_trk_1
10.89.129.226   1720  10.89.129.226   51534 horse             VOIP-GW
    E164-ID: 2000
    H323-ID: psy-gw-01@maui-onions.com
Total number of active registrations = 2
Parameter Description
E164-ID: 2000 This is the destination pattern on POTS dial peer 1 on the Cisco IOS gateway router.

Note: In this case, this is an FXS port, so it connects to an end station (which, in this case, is the analog phone shown in the Network Diagram).

dial-peer voice 1 pots
 destination-pattern 2000
 port 1/0/1
H323-ID: psy-gw-01 This is the h.323-id parameter on the Fast Ethernet interface of the Cisco IOS gateway router.
h323-gateway voip h323-id psy-gw-01
H323-ID: h225_trk_1 This is the H.225 trunk that is configured in the Cisco CallManager server.

Use the show gateway Command on the Cisco IOS Gateway to Verify Its Registration Status

Use the show gateway command on the Cisco IOS gateway to verify that the gateway has registered with the gatekeeper.

psy-gw-01# show gateway
H.323 ITU-T Version: 4.0   H323 Stack Version: 0.1
 Gateway  psy-gw-01@maui-onions.com  is registered to Gatekeeper horse
 
Alias list (CLI configured)
H323-ID psy-gw-01@maui-onions.com 
E164-ID 2000
Alias list (last RCF)
H323-ID psy-gw-01@maui-onions.com 
E164-ID 2000

H323 resource thresholding is Disabled

This output shows that the Cisco IOS gateway has registered with the gatekeeper.

Make Calls in Both Directions to Verify Connectivity

You must try to make calls in both directions to ensure that your dial plan is correct and that the gatekeeper functions for calls that either phone initiates.

  1. Call the IP phone from the analog phone.

    You should successfully establish a call and have two-way voice communication.

    Even if you cannot make the call successfully, proceed to Step 2.

  2. Call the analog phone from the IP phone.

    You should successfully establish a call and have two-way voice communication.

    If you can successfully make calls in both directions, proceed to the next section, Use the show gatekeeper calls Command to Verify That CAC Is Working, to verify that the calls you make use CAC.

    If you only have one-way voice communication, see the Related Information

Related Cisco Support Community Discussions section for links to other documents on how to troubleshoot one-way voice issues. After you have resolved the one-way voice problem, proceed to the section Use the show gatekeeper calls Command to Verify That CAC Is Working.

If you cannot place a call in either direction, or in both directions, see the Troubleshoot section of this document.

Use the show gatekeeper calls Command to Verify That CAC Is Working

This section helps you to verify that the calls you make use CAC.

  1. Make a call from the analog phone (2000) to the IP phone (1006) and leave both phones off hook.

  2. Issue the show gatekeeper calls command to view an active call.

    psy-gk-01# show gatekeeper calls
    Total number of active calls = 1.
    GATEKEEPER CALL INFO
    ====================
    LocalCallID Age(secs) BW
    35-24077 14 128(Kbps)
    Endpt(s): Alias E.164Addr
    src EP: psy-gw-01@maui-onions 2000
    CallSignalAddr Port RASSignalAddr Port
    10.89.129.226 1720 10.89.129.226 51534
    Endpt(s): Alias E.164Addr
    dst EP: h225_trk_1 1006
    CallSignalAddr Port RASSignalAddr Port
    10.89.129.211 3821 10.89.129.211 1494

    This output shows that CAC is active for this call. Boldface text shows the source and destination DNs (1006 and 2000).

  3. Make a call from the IP phone (1006) to the analog phone (2000) and leave both phones off hook.

  4. Issue the show gatekeeper calls command to view an active call.

    psy-gk-01# show gatekeeper calls
    Total number of active calls = 1.
                             GATEKEEPER CALL INFO
                             ====================
    LocalCallID                        Age(secs)   BW
    36-32986                           8           16(Kbps)
     Endpt(s): Alias                 E.164Addr
       src EP: h225_trk_1            1006
               CallSignalAddr  Port  RASSignalAddr   Port
               10.89.129.211   3821  10.89.129.211   1494
     Endpt(s): Alias                 E.164Addr
       dst EP: psy-gw-01             2000
               CallSignalAddr  Port  RASSignalAddr   Port
               10.89.129.226   1720  10.89.129.226   51534
    

    This output shows that CAC is active for this call. Boldface text shows the source and destination DNs (1006 and 2000).

Reduce the Zone Bandwidth Parameter to Block All Calls

If you want to perform a final, conclusive test that CAC is operational, reduce the zone bandwidth parameter to less than 128. Based on the output from the show gatekeeper calls command, 128 is the bandwidth that the calls use. (This is shown in the section Use the show gatekeeper calls Command to Verify That CAC Is Working.)

  1. Shut down the gatekeeper.

    psy-gk-01(config)# gatekeeper
    psy-gk-01(config-gk)# shutdown
    
  2. Issue the command to reduce the zone bandwidth.

    psy-gk-01(config-gk)# bandwidth total zone horse 64
    
  3. Bring the gatekeeper online again.

    psy-gk-01(config-gk)# no shutdown
    

    You should get an immediate reorder tone after you dial the fourth digit of either DN. If you do not get a reorder tone and the call goes through, you may not have changed the route pattern on the Cisco CallManager server to point to the H.225 trunk (h225_trk). Verify this setting. You should also verify that you made the change to the zone bandwidth parameter.

  4. Remember to change the zone bandwidth back to a value that allows the calls to proceed.

Troubleshoot

This section provides information you can use to troubleshoot your configuration.

Troubleshoot the Gatekeeper Configuration

Complete these steps to troubleshoot your configuration:

  1. If your gateways do not register with the gatekeeper and you have verified that all your configuration commands are correct, refer to the document Troubleshooting Gatekeeper Registration Issues.

  2. If your gateways register with the gatekeeper and you cannot place calls in either or in both directions:

    • Verify that you have the zone prefix commands for your DNs on the gatekeeper.

    • Verify that the zone bandwidth is not set below 128.

    • Stop and restart the Cisco CallManager service on the server.

    • Shut down the gatekeeper and restart it.

    • Switch your Cisco CallManager route pattern back to the gateway that you used to verify the Requirements for this document. Ensure that you can place calls in both directions without CAC. If you cannot place calls with your original gateway, you need to resolve the problem before you can successfully test CAC.

    There are several other documents available on Cisco.com that explain how to verify and troubleshoot gatekeeper configurations in greater detail. See the Related Information

Updated: Jan 20, 2006
Document ID: 42063