External Hot Desking - Conditions

Licensing

Feature Interactions

Outbound Calls to the External Hot Desk User

Inbound Calls from the External Hot Desk User

Mid-Call Features

Transit Node Handling

When an EHDU user is active on a transit node, the node is treated as an endpoint. As an endpoint, it acts on DPNSs messages instead of passing them on as expected since invoking a feature—such as transfer, forwarding, or route optimization—could clear the transit node from the call-signalling path. When this occurs the EHDU user no longer have access to mid-call features and the user state returns to idle. To illustrate the behavior, consider the following examples:

Call Diversion

Normally, when an off-PBX diversion occurs on a network call, the diverting controller sends a divert request to the originating PBX. This request contains the digits required to route to the forwarding destination. The originating PBX then extends the call to the forwarding destination and releases the trunk that signalled the diversion. If the EHDU node that is acting as a transit node does not intercept the diversion request, it will be released when the originating node attempts to divert the call.

Figure 1 shows a call from an EHDU user whose home node is ICP B to extension 1000. Extension 1000 is Call Forward Always to extension 2000. When the diversion occurs, the new call is extended from ICP A to ICP D. ICPs B and C are no longer in the call path which means the state of the EHDU is lost. To solve this problem, the node hosting the EHDU (ICP B) will act as a diversion branching node and will perform all diversion requests as shown in Figure 2.

Transfer

Standard transfer signalling in a DPNSS network causes an exchange of the end point identities. When an EHDU user is active on a transit node, the messages containing the transfer information is passed and the endpoint PBX exchanges the users' PSTN identity, and not the internal identity. This is because the PSTN gateway is not aware that the call is an EHDU and does not have the internal name and number to send back in the identity exchange (shown in Figure 3). To remedy this situation, the node hosting the EHDU will exchange the transfer signals as shown in Figure 4.

Music on Hold

When a caller in the network places an EHDU on hold, the EHDU hears the music source of its home node, as shown in Figure 5, and not the PSTN gateway node as expected in the typical DPNSS transit case.

If the holding party has "Local Music on hold source" (LMOH) enabled in their Class of Service, the EHDU user will hear the music source of the holding party's ICP as shown in Figure 6.