Dynamic Channel Reservation

Owned by Kelli Higdon
Last updated: Apr 03, 2024
5 min read

 

 

Dynamic Channels Reservation gives a user the ability to reserve a given number of TDM channels in a channel group so they are designated as Incoming Only. The number of channels reserved is configured in the Channel Group object and is configured as a percentage of the available channels (Out Of Service channels are not included) within that channel group. The available channels are allocated in Real Time so the number of channels available can change during call processing. The Dynamic Channel Reservation feature is supported in channel groups configured as either SS7 or ISDN and is supported when the channels are initially configured as Incoming/Outgoing only.

The Dynamic Channel Reservation feature functions as long as there are more channels available on that channel group than what is configured to be allocated in the feature. When the channel group has more available channels than the number of reserved channels configured, the channels available in this instance are automatically set to Incoming/Outgoing and can receive and transmit calls. However, if the number of channels available on that channel group is the same or less than what is configured, the remaining channels are automatically set to Incoming Only. Refer to example below.

Example of Channel Usage

The Dynamic Channel Reservation feature configures a set number of channels as Incoming Only. What to do with the remaining channels after the Incoming Only channels have been allocated is described in the example below.

The table below displays how the channels within a channel group are allocated for either incoming only, outgoing only, or incoming/outgoing. When the total number of channels in the channel group is more than what is configured to be allocated as Incoming Only (Dynamic Channel Reservation), the remaining channels also need to be allocated as incoming, outgoing, or incoming/outgoing. The table below displays what would happen when a channel group with 32 total channels, allocates 10% of the channels to be incoming only. What would happen to the remaining channels.

# of Channels in Channel Group

# of Currently Active Channels

# of available channels (Total-Active)

Reserved Channels(10% of 32 rounded up)

Allowable Channel Usage at next call

32

27

5

4

Incoming, Outgoing

32

29

3

4

Incoming Only

32

30

2

4

Incoming Only

32

28

4

4

Incoming Only 

Row 1:

In Row 1, the channel group has 32 channels configured. Of the 32 channels, 27 channels are being used at any instant in time. This leaves the # of available channels at that instant in time at 5. The Reserved Incoming Channels (%) field in the channel group object has been set to 10 % which when rounded up is 4. Since the number of available channels is larger than the number of reserved channels configured, the channel allocated for the next call will be set to Incoming/Outgoing.

Row 2:

In Row 2, the channel group has 32 channels configured. Of the 32 channels, 29 channels are being used at any instant in time. This leaves the # of available channels at that instant in time at 3. The Reserved Incoming Channels (%) field in the channel group object has been set to 10 % which when rounded up is 4. Since the number of available channels is smaller than the number of reserved channels configured, the channel allocated for the next call will be set to Incoming Only.

Row 3:

In Row 3, the channel group has 32 channels configured. Of the 32 channels, 30 channels are being used at any instant in time. This leaves the # of available channels at that instant in time at 2. The Reserved Incoming Channels (%) field in the channel group object has been set to 10 % which when rounded up is 4. Since the number of available channels is smaller than the number of reserved channels configured, the channel allocated for the next call will be set to Incoming Only.

Row 4:

In Row 4, the channel group has 32 channels configured. Of the 32 channels, 28 channels are being used at any instant in time. This leaves the # of available channels at that instant in time at 4. The Reserved Incoming Channels (%) field in the channel group object has been set to 10 % which when rounded up is 4. Since the number of available channels is equal to the number of reserved channels configured, the channel allocated for the next call will be set to Incoming/Outgoing. 

Configuration

The Dynamic Channel Reservation feature is configured using the Reserved Incoming Channels (%) field in the Channel Group object. In the Reserved Incoming Channel (%) field, select from the drop down menu the percentage of channels that will be configured as Incoming Only. Once set, the percentage of the total number of In Service channels are allocated as Incoming Only. Below is screen capture displaying the relevant field that needs to be configured for the feature to function. In the screen capture, 5% of the total number of available channels (Out Of Service channels are not included) are being set to be Incoming Only.

 

Call Tracing

When the Dynamic Channel Reservation is configured and functioning, the call trace will display log messages indicating the number of channels available and the total number of non-OOS channels in the channel group.

14:16:05.377 CALL(L4)  (00:00001:01) Dynamic Channels Reservation - Free Count:29/29  Reserved Count:10% (3)


If the routed call is rejected due to the reserved incoming channels, log messages will display this

14:21:42.037 CALL(L4)  (00:00002:01) Dynamic Channels Reservation - Free Count:3/29  Reserved Count:10% (3) 14:21:42.037 CALL(L4)  (00:00002:01) Dynamic Channels Reservation - Call Route Rejected: No free channels for outgoing route(3/29)

Additional Information

General Information

  • Dynamic Channel Reservation functionality is supported on SS7 and ISDN channel groups only.

  • When configuring the Channel Group, the Channel Group Function field must be set to Incoming/Outgoing Trunks.

  • If call is routed to a channel group where there are no more outgoing channels available, the 2020 IMG will reject it with cause code 34 (No circuit/channel available).

Reserved Channels (Dynamic Channel Reservation)

  • The configured value of Reserved Channels represents the total number of non Out Of Service channels in the Channel Group.

  • Any SS7 CICs configured as Blocked are not excluded from the percentage calculation.

  • The number of reserved channels is calculated as the total number of non-OOS channels times the percentage value configured in the Reserved Incoming Channels (%) field. After performing the calculation, the number of reserved channels is always rounded up to the next whole number.

  • Before each call is routed out to a channel group, the number of reserved channels is calculated in Real Time.

Host

  • As described above, the Reserved Incoming Channels field configures the percentage from drop down menu which ranges from 0 to 100%. The default value is 0%.

  • For the feature to function correctly, the Channel Group Function field must be set to Incoming and Outgoing trunks.

  • The Reserved Incoming Channels field will be greened out and cannot be configured if the channel group is configured as any protocol other than SS7 or ISDN.

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