# Direct Station Selection/Busy Lamp Field (DSS/BLF)

## Description

A Busy Lamp Field (BLF) shows the status of a directory number or device next to a telephone or Programmable Key Module (PKM) line key. The key associated with the lamp acts as a Direct Station Select (DSS) key. The monitored device may be on the same system or on another system within the same cluster.

A Busy Lamp Field (BLF) shows the status (busy, ringing, DND, Call Forward Always active, Hot Desk user logged out, or idle) of a directory number or device next to a telephone line key or Programmable Key Module (PKM) key. The monitored device may be on the same or on another system within the same cluster.

NOTE: When the DND or CFA status of the monitored device changes, the DSS/BLF appearance on the monitoring device may take few seconds to update.

The key associated with the lamp acts as a Direct Station Select (DSS) key allowing the user to direct calls based on the call states of the set hosting the lamp and the device being monitored. Typical uses of DSS keys associated with busy lamps are directed Call Pickup and secretarial Transfer of calls on soft hold.

## Conditions and Feature Interactions

### Single System Environment

- Busy lamps are supported on IP telephones, as well as PKMs.

- When a SIP device goes off-hook, the BLF will not indicate it until the call becomes active.

- A device or directory number cannot exceed a total of 64 local and remote busy lamp appearances.

- All busy lamp programming is preserved in a data save.

- If the line is a multicall line, a busy indication signifies that all group members are busy. A ringing indication signifies that at least one group member is ringing. An idle indication signifies that at least one group member is idle. A Do Not Disturb indication signifies that all group members' sets are in DND.

- Multiline sets and associated PKMs are limited to one busy lamp per monitored directory number. There is no limit on the number of buttons which may be configured as DSS/BLF appearances on a particular set.

- A delay ring is not programmable on DSS or Secretarial Transfer keys.

- The "Call Forwarding Always - Line Status Indicator ON (Yes/No)" field in the System Options form does not apply to DSS/BLF keys.

- A host set's busy lamps are refreshed upon set recovery.

- Call Forward Always (CFA) BLF indication is the lowest priority indication (next to idle) for monitored devices in idle state. Thus, if an idle device with CFA active is also in DND, the BLF will indicate DND, not CFA.

- The following conditions apply to BLF indication of Hot Desk user logout (out of service):

- When a Hot Desk user logs out, the BLF indication of logged out status (lamp extinguishes) has priority over all other BLF indicator states.

- BLF indication of logged out Hot Desk users is supported by phones, PKMs, and IP Console applications( MiVoice Business Console). Other consoles do not support this feature.

- BLF indication of logout status only applies to Hot desk users.

- Monitored DNs may be local to the controller or may reside on another controller within the cluster. When the monitoring and device and monitored device are on different systems, both systems must be running 3300 ICP Release 8.0 UR3 software or later.

- Resiliency is supported for this feature if the monitoring device is an IP Phone or IP PKM but not if the monitoring device is an IP Console application( MiVoice Business Console). While an IP Console application( MiVoice Business Console) is registered on its secondary controller, busy lamp functions are not available.

- In a resilient configuration, a resilient monitored device displays logged out status only if the device is logged out from both controllers (primary as well as secondary).

### Clustered System Environment (Remote DSS/BLF)

- Remote DSS/BLF functions across an MSDN/DPNSS network or an IP trunking network. To operate across a network, systems must be clustered. The cluster must support RDN Synchronization.

- Feature DNs must be programmed in the Cluster Elements form. The Feature DNs must have the same digit length as the system CEID digits. (See Voice Clustering Programming for an overview of cluster programming).

- A device or directory number cannot exceed a total of 64 local and remote busy lamp appearances.

- It is recommended that no more than four remote systems carry busy lamp representations of the same device. Exceeding this recommended limit may cause BLF performance to deteriorate. The maximum number of systems that can host BLF appearances of the same device is 32.

- When a system is initialized in a single or clustered environment, local busy lamps will indicate the initial state of the monitored device. Remote busy lamps are updated upon the first call activity involving their respected monitored device.

- In a clustered system environment, busy lamps are not automatically refreshed upon inter-system trunk recovery. See the BLF REFRESH maintenance command for more information.

- In a clustered system environment, if a receiving system switches activity, busy lamp indications are not automatically updated as a result of the activity switch. Busy lamp indications are updated upon the next call activity by their respective monitored devices on the broadcasting system(s). If a DSS key is used prior to call activity by its remote monitored device, the device's status is assumed to be idle/no DND and the DSS key acts on this status.

- In a MiVoice Business clustered environment, if a resilient device is programmed with DSS/BLF keys, then you must also program the DSS/BLF keys on the devices's secondary controller.

### All Environments

- Photo avatars available to 69xx IP Phones (excluding 6905 and 6910) are not supported on DSS/BLF keys.

## Programming

### Single System Environment

To program a DSS/BLF key in a single system environment:

NOTE: A directory number must already exist in the system before you can program a key and busy lamp to monitor it.

1. Multiline Set Keys form

- Select the Directory Number of the set that you want to assign the DSS/BLF key to.

- In the lower frame, select the Button Number of the key.

- Click Change Member.

- In the Button Label field, enter a description for the key.

- In the Line Type field, select DSS/Busy Lamp for regular operation. To allow secretarial transfer, select Secretarial.

- In the Button Directory Number field, enter the directory number that you want the DSS/BLF key to monitor.

- In the Ring Type field, select Ring, Ring Continuous or No Ring. Selecting Ring will cause the set hosting the busy lamp to issue a single burst of ringing when the lamp first indicates ringing state.

- Click Save.

2. (Optional) System Options form

Enable the following if required:

2. BLF - Busy Indication Based on Set Enabled

3. BLF - CFA Indication Based on Set Enabled

### Clustered System Environment

To program a DSS/BLF key across two elements in a cluster:

At the local switch, program the DSS/BLF key on the device

1. Cluster Elements form

- Ensure that a both the local and remote elements are assigned a unique Feature DN number.

2. Multiline Set Keys form

- Select the Directory Number of the set that you want to assign the DSS/BLF key to.

- In the lower frame, select the Button Number of the key.

- Click Change Member.

- In the Button Label field, enter a description for the key.

- In the Line Type field, select DSS/Busy Lamp for regular operation. To allow secretarial transfer, select Secretarial.

- In the Button Directory Number field, enter the directory number of the device on the remote switch that you want the DSS/BLF key to monitor.

- In the Ring Type field, select Ring, Ring Continuous or No Ring. Selecting Ring will cause the set hosting the busy lamp to issue a single burst of ringing when the lamp first indicates ringing state.

- Click Save.

On the remote switch, program the extension number of the monitoring set into the Remote Busy Lamps form.

- Remote Busy Lamps form

1. Click Add and enter the directory number of the device that you want the DSS/BLF key to monitor.

2. Click Save.

3. Select the newly added monitored device.

4. In the bottom frame, click Add Member.

5. In the Remote Host Set Directory Number field, enter the directory number of the monitoring device (the directory number on the local switch as entered in the preceding procedure.)

6. Click Save.

In the Class of Service of the IP trunk(s), set the following option:

- Class of Service Options form

- Public Trunk = No.

(Optional) At both the local switch and remote switch(es), enable the following options:

- System Options form

- BLF - Busy Indication Based on Set Enabled

- BLF - CFA Indication Based on Set Enabled

CAUTION: If you do not complete the programming on both switches error logs will be generated. For example, if you set up a DSS/BLF key on the local switch without completing the Remote Busy Lamps form on the remote switch, error logs will be generated at the remote switch.

## Device Support

- Supported on all devices.

## Operation

See Direct Station Select for information about using this feature.