1. EAGLE LNP Application Processor Administration and LNP Feature Activation Guide
  2. Automatic Call Gapping (ACG) Configuration

11 Automatic Call Gapping (ACG) Configuration

This chapter describes how to determine traffic capacity and node overload control levels, and how to add and remove ACG node overload control levels and ACG manual initiated controls.

11.1 Overview

Location routing number (LRN) queries for a particular telephone number or a portion of a telephone number are received by the EAGLE when a particular threshold is reached. ACG controls are used under two conditions:

  1. When a node overload condition is detected and an ACG control is configured for that overload level, the EAGLE sends an ACG component within each LRN query response it processes. The ACG control is invoked for the first 6 or 10 digits of the called party address in all queries sent to the EAGLE to control the rate that queries are processed.

  2. If no overload control is in place, LRNQT sends an ACG for a manually initiated control to block queries. Manually initiated control procedures are similar to overload control procedures, but shall be able to vary the number of digits that are to be placed under control (3 or 6-10 digits). Since LRNQT may have to process queries for ported (LRN routing) and non-ported numbers (default routing), the user shall be able to initiate control on any number. A list of all numbers for which the user has initiated controls shall be maintained. This list shall be the same across AIN and LRNQT services.

    If no overload control is sent, the EAGLE sends an ACG for a manually initiated control to control the rate of queries for a particular area code (3 digits), area code and prefix (6 digits), 10 digit telephone number, or part of a 10 digit telephone number (6 to 10 digits) are processed. The database can contain a maximum of 256 manually initiated ACG controls.

    In addition to the digits applied to the ACG control, the ACG control contains a duration index and a gap interval index. The duration index is a timer defining the amount of time the ACG control is in effect. The gap interval index is a timer that defines the rate that queries are processed in the EAGLE. For example, the ACG control may be in effect for 128 seconds, the duration index, and a query is processed every 2 seconds, the gap interval index. When the ACG control is detected, the duration timer and gap interval timer are started. Until the gap timer expires, all calls containing the specified number of digits or the specified digits are routed to reorder tone or to an announcement indicating that the call cannot be completed. Once the gap timer has expired, the next call containing the matching dialed digits is processed normally and the gap timer is restarted. This cycle continues until the ACG control is cancelled by the EAGLE or the duration timer expires. Table 11-1 shows the values for the duration index and the gap index used in the automatic call gapping commands.

    Table 11-1 Duration and Gap Interval Index Values

    Index Duration Index Value (DRTN) in seconds Node Overload Control Interval or IN Manual Initiated Control Interval Index Value (INTVL) in seconds AIN Manual Initiated Control Interval Index Value (AINTVL) in seconds

    0

    N/A

    0

    N/A

    1

    1

    3

    0

    2

    2

    4

    0.1

    3

    4

    6

    0.25

    4

    8

    8

    0.5

    5

    16

    11

    1

    6

    32

    16

    2

    7

    64

    22

    5

    8

    128

    30

    10

    9

    256

    42

    15

    10

    512

    58

    30

    11

    1024

    81

    60

    12

    2048

    112

    120

    13

    infinite

    156

    300

    14

    N/A

    217

    600

    15

    N/A

    300

    infinite

Node Overload Control

The EAGLE does not maintain overload levels for individual subsystems, but maintains an overload level for the entire EAGLE, the node. There are 10 overload levels that are defined for the EAGLE. Each overload level contains the following information.

  • The number of queries in a 30-second period that defines each overload level. When the defined number of queries is reached, the ACG control for the overload level goes into effect.

  • The number of digits to control from AIN queries

  • The number of digits to control from IN queries

  • The duration index of the ACG control

  • The gap interval index of the ACG control

Only overload levels 1 through 9 can be added or removed from the database; level 10 cannot be removed but can be changed. Overload level 10 is predefined with the following values:
  • The number of queries = 2,147,483,647
  • The number of digits from AIN queries to control = 6
  • The number of digits from IN queries to control = 6
  • The gap interval index = 7 - 22 seconds
  • The duration index = 1 - 1 second

Any overload levels that are not configured are not used. If no overload levels are configured or if any LIMs are denied SCCP service, then overload level 10 is used for the ACG node overload control.

Manually Initiated Control

Manually initiated controls are applied to a specific 10-digit telephone number or to a part of a specific telephone number in either AIN queries or IN queries. The manually initiated control can contain the first 3, 6, 7, 8, or 9 digits, or all 10 digits, of the telephone number.

The duration index of a manually initiated control uses the same values as the duration index of a node overload control.

A manually initiated control contains a gap interval index for IN queries, using the same values as the gap interval index for the node overload control levels, and a gap interval index for AIN queries using different values.

For IN queries, the digits sent for manually initiated controls are the original 10 digits of the Called Party Number. For example, if a query for Called Party Number 919-460-2132 triggers a manually initiated control for the digits 919, the digits parameter of the ACG is 919-460-2132 instead of 919.

A manually initiated control can be applied to all queries sent to the EAGLE. This type of manually initiated control specifies the number of digits from the dialed digits of the query. For manually initiated controls that apply to particular query services and Called Party digits, the number of digits to use in the ACG component is the number of digits in the specified digit string.

The database can contain a manually initiated control that applies to all queries and manually initiated controls that apply to specific combinations of query service and Called Party digits. When more than one control applies to a specific query, the one selected is the one containing the higher number of digits. If a manually initiated control cannot be selected with the number of digits, then the control with the higher gap interval index value is selected. If the controls contain the same gap interval index value, then the control with the higher duration index value is selected. The following example illustrates how the controls are selected.

  1. A control for AIN LNP queries for Called Party digits of 919-460-2 is entered into the database. (ent-acg-mic:serv=ain:aintvl=1:dgts=9194602:drtn=3).

  2. A control with an interval index of 10 for AIN LNP queries for Called Party digits of 919-460 is entered into the database. (ent-acg-mic:aintvl=10:serv=ain:dgts=919460:drtn=12:).

  3. A control with an interval index of 7 for all queries, and the number of digits used for the control is 6, is entered into the database. (ent-acg-mic:intvl=7:type=all:nd=6:drtn=12:aintvl=7)

  4. The EAGLE receives an AIN query for the Called Party Address 919-461-1017.

  5. The EAGLE sends an ACG for 919-461. The control entered in item 3 is the only one that applies.

  6. The EAGLE receives an AIN query for Called Party Address 919-460-2132.

  7. The EAGLE sends ACG for 919-460-2. The control entered in item 1 is more specific than the controls entered in items 2 and 3.

  8. The EAGLE receives an AIN query for Called Party Address 919-460-5500.

  9. The EAGLE sends ACG with a interval index of 10 for 919-460. The control entered in item 2 is more specific than the control entered in item 3. The control entered in item 1 does not apply.

11.2 Determining the ACG Node Overload Control Level Query Rates

The query rates for the ACG node overload control levels are the number of LNP queries (messages or transactions) received by the EAGLE in a 30-second period. When the defined number of queries is reached, the ACG control for that node overload control level goes into effect.

The following values are used to calculate the query rates for the node overload control levels.
  • N = the number of Service Module cards cards running the VSCCP application installed in the EAGLE.
  • S = the total EAGLE SCCP traffic capacity in messages per second
  • P = The LNP query portion of the SCCP traffic, from 0% to 100%, determined from the traffic studies.
  • Q = The LNP query portion of the total EAGLE SCCP traffic capacity in messages per second
  • F = The query rate of the first ACG node overload control level at 80% of the total LNP query portion of the SCCP traffic, in messages per 30 seconds
  • L = The query rate of the last ACG node overload control level at 100% of the total SCCP traffic, in messages per 30 seconds
  • NL = The number of ACG node overload control levels being used.
  • I = The increment of the query rate between the node overload control levels.

The query rates are configured with the qr parameter of ent-acg-noc and chg-acg-noc commands.

Any node overload control levels that are not configured are not used. If no node overload control levels are configured or if any LIMs are denied SCCP service, then node overload control level 10 is used for the ACG node overload control. Node overload control level 10 cannot be added with the ent-acg-noc command or removed with the dlt-acg-noc command, but can be changed with the chg-acg-noc command. It is recommended that the query rate for node overload control level 10 is not changed. The default query rate for node overload control level 10 is 2,147,483,647 messages per 30 seconds.

Caution:

If the query rate for node overload control level 10 is changed, then node overload control level 10 is used as any other node overload control level, in addition to the default conditions that node overload control level 10 is used for (no node overload control levels are configured or for any LIMs denied SCCP service). If the query rate for node overload control level 10 is changed, make sure that the duration and interval timer values assigned to node overload control level 10 are appropriate for all three conditions or traffic may be lost.

When the query rate of node overload control level 10 is not changed, node overload control level 10 is used only for its default conditions and is not treated as another node overload control level.

Determining the Total EAGLE SCCP Traffic Capacity (S)

The total EAGLE traffic capacity is determined from the number of Service Module cards running the VSCCP application installed in the EAGLE (N). LNP requires E5-SM4G cards and E5-SM8G-B cards as Service Module cards. E5-SM4G cards can operate at either 5000 transactions (or messages) per second (TPS) or 6800 TPS, depending on the enabled quantity of the E5-SM4G Throughput Capacity feature in the EAGLE. E5-SM8G-B cards can operate at 5000, 6800, or 10,000 TPS, depending on the enabled quantity of the E5-SM4G Throughput Capacity feature in the EAGLE. The number of Service Module cards used in this calculation is one less than the total number of Service Module cards in the EAGLE. One Service Module card is used as a standby card.

To determine the total EAGLE SCCP traffic capacity (S), subtract 1 from the total number of Service Module cards running the VSCCP application and multiply the result by the enabled E5-SM4G/E5-SM8G-B card TPS value.

(N-1) x <E5-SM4G/E5-SM8G-B TPS> = Total SCCP traffic capacity (S)

Determining the LNP Query Portion of the Total SCCP EAGLE Traffic Capacity (Q)

The LNP query portion of the SCCP traffic (Q) is a percentage of the total EAGLE SCCP traffic (P) as determined from the traffic studies.

After the LNP query percentage is determined, multiply the total EAGLE SCCP traffic capacity (S) by the LNP query percentage.

S x P = Q

Determining the Query Rate of the First ACG Node Overload Control Level (F)

The ACG node overload controls should start when the LNP query portion of the SCCP traffic reaches 80% of the total LNP query portion of the SCCP traffic (Q). The ACG node overload control level is determined by the number of messages received over a 30 second period of time.

To determine the query rate of the first ACG node overload control level (F), in messages per 30 seconds, multiply the total LNP query portion of the SCCP traffic (Q) by 0.8, then multiply that result by 30.

Q x 0.8 x 30 = F

Determining the Query Rate of the Last ACG Node Overload Control Level (L)

The ACG node overload controls should continue until the LNP query portion of the SCCP traffic reaches 100% of the total SCCP traffic (S).

To determine the query rate of the last ACG node overload control level (L), in messages per 30 seconds, multiply the total LNP query portion of the SCCP traffic by 30.

S x 30 = L

Determining the Increment of Query Rates between ACG Node Overload Control Levels (I)

If the number of ACG node overload control levels being used is 3 or more, the query rates of each node overload control level between the first and the last node overload control level can be evenly divided.

Subtract the query rate of the first level from the query rate of the last level and divide the result by the number of node overload control levels (NL) being used minus 1.

(L - F)/(NL-1) = I

Setting the Query Rate for ACG Node Overload Control Levels

To determine the query rate for each ACG NOC level after the first level and before the last level, add the increment value (I) to each successive level. For example,

If three node overload control levels are being used:

  • The query rate for the first node control level = F
  • The query rate for the second node control level = F + I
  • The query rate for the third node control level = L

If four node overload control levels are being used:

  • The query rate for the first node control level = F
  • The query rate for the second node control level = F + I
  • The query rate for the third node control level = F + 2I
  • The query rate for the fourth node control level = L

If nine node overload control levels are being used:

  • The query rate for the first node control level = F
  • The query rate for the second node control level = F + I
  • The query rate for the third node control level = F + 2I
  • The query rate for the fourth node control level = F + 3I
  • The query rate for the fifth node control level = F + 4I
  • The query rate for the sixth node control level = F + 5I
  • The query rate for the seventh node control level = F + 6I
  • The query rate for the eighth node control level = F + 7I
  • The query rate for the ninth node control level = L

ACG NOC Configuration Examples

Table 11-2 illustrates ACG NOC configuration for different numbers of ACG NOC levels, Service Module cards, and E5-SM4G/E5-SM8G-B TPS rates.

Table 11-2 ACG NOC Configuration Examples

Example 1 2

Configuration:

P=% LNP Query traffic

N=Service Module cards

NL=Number of ACG NOC levels

Card TPS rate

P=0.7 (70%)

N=21

NL=7 (3-9)

5000 TPS

P=0.6 (60%)

N=17

NL=4 (2, 4, 6, 8)

6800 TPS

1. Total SCCP traffic capacity

(N-1) x 5000 = S

20 x 5000 = 100000

(N-1) x 6800 = S

16 x 6800 = 108800

2. LNP Query portion of SCCP traffic

S x P = Q

100000 x 0.7 = 70000 TPS

S x P = Q

108800 x 0.6 = 652800 TPS

3. Query rate of first ACG NOC level

Q x 0.8 x 30 = F

70000 x 0.8 x 30 = 1680000

Q x 0.8 X 30 = F

652800 x 0.8 x 30 = 1566720

4. Query rate of last ACG NOC level

S x 30 = L

100000 x 30 = 3000000

S x 30 = L

108800 x 30 = 3264000

5. Increment between levels

(L-F)/(NL-1) = I

(3000000-1680000)/6 = 220000

(L-F)/(NL-1) = I

(3264000-1566720)/3 = 565760

6. Commands to set levels - see Table 11-3.

The commands in Table 11-3 could be used to set the ACG NOC levels for Example 1 and Example 2 in Table 11-2.

Table 11-3 Commands to Set ACG NOC Levels in Example 1 and Example 2

Example 1 Example 2
ent-acg-noc:lvl=3:qr=1680000:drtn=3:intvl=3 ent-acg-noc:lvl=4:qr=1900000:drtn=4:intvl=4 ent-acg-noc:lvl=5:qr=2120000:drtn=5:intvl=5 ent-acg-noc:lvl=6:qr=2340000:drtn=6:intvl=6 ent-acg-noc:lvl=7:qr=2560000:drtn=7:intvl=7 ent-acg-noc:lvl=8:qr=2780000:drtn=8:intvl=8 ent-acg-noc:lvl=9:qr=3000000:drtn=9:intvl=9 ent-acg-noc:lvl=2:qr=1566720:drtn=3:intvl=3 ent-acg-noc:lvl=4:qr=2132480:drtn=4:intvl=4 ent-acg-noc:lvl=6:qr=2698240:drtn=6:intvl=6 ent-acg-noc:lvl=8:qr=3264000:drtn=8:intvl=8

11.3 Adding an ACG Node Overload Control Level

This procedure is used to add an ACG node overload control level to the database using the ent-acg-noc command.

Refer to Commands User's Guide for a complete description of the ent/chg/rtrv-acg-noc commands, including parameter names, valid values, rules for using the command correctly, and output examples.

The interval index is the amount of time between ACGs. This is a number that is mapped to a time value at the LNP node. See Table 11-1.

The duration index is the amount of time that the ACG is in effect. This is a number that is mapped to a time value at the LNP node. See Table 11-1.

Overload level 10 is predefined in the database and cannot be added to or removed from the database. Its values can be changed, though it is recommended that they not be changed. See Node Overload Control.

Prerequisite for Adding an ACG NOC Level

Before an ACG node overload control can be added, the LNP feature must be enabled.
  • Enter the rtrv-ctrl-feat command to display the controlled features that are enabled in the system.
  • If the LNP feature is enabled, the entry LNP ported TNs is shown in the rtrv-ctrl-feat output with a quantity greater than 0. Continue wit the procedure in this section.
  • If the LNP feature is not enabled, perform the procedures in the LNP Feature Configuration to enable the LNP feature. Then continue with the procedure in this section.
  1. Display the ACG node overload levels in the database by entering the rtrv-acg-noc command.
    Verify that the ACG NOC level that is to be added is not already in the database.
  2. Add the ACG node overload control level to the database using the ent-acg-noc command.

    See Determining the ACG Node Overload Control Level Query Rates for an explanation of how to determine the Query Rate for the level.

  3. Verify the changes using the rtrv-acg-noc command.
  4. Back up the changes using the chg-db:action=backup:dest=fixed command.
    The following messages appear, the active Maintenance and Administration Subsystem Processor (MASP) appears first. 
    
BACKUP (FIXED): MASP A - Backup starts on active MASP.
BACKUP (FIXED): MASP A - Backup on active MASP to fixed disk complete.
BACKUP (FIXED): MASP A - Backup starts on standby MASP.
BACKUP (FIXED): MASP A - Backup on standby MASP to fixed disk complete.

11.4 Removing an ACG Node Overload Control Level

This procedure is used to remove an ACG Node Overload Control Level from the database using the dlt-acg-noc command.

The dlt-acg-noc command uses only one parameter, lvl – the overload levels 1 though 9. The database contains 10 ACG node overload levels, but only nine can be added or removed.

Overload level 10 cannot be removed from the database, but its values can be changed using the Changing an ACG Node Overload Control Level procedure.

The overload level to be removed must be in the database.

Refer to Commands User's Guide for complete descriptions of the commands that are used in the following procedure, including parameter names, valid values, rules for using the command correctly, and output examples.

  1. Display the ACG node overload levels in the database by entering the rtrv-acg-noc command.
  2. Remove the ACG node overload control level from the database using the dlt-acg-noc command.
  3. Verify the changes using the rtrv-acg-noc command.
  4. Back up the changes using the chg-db:action=backup:dest=fixed command.
    The following messages appear, the active Maintenance and Administration Subsystem Processor (MASP) appears first. 
    
BACKUP (FIXED): MASP A - Backup starts on active MASP.
BACKUP (FIXED): MASP A - Backup on active MASP to fixed disk complete.
BACKUP (FIXED): MASP A - Backup starts on standby MASP.
BACKUP (FIXED): MASP A - Backup on standby MASP to fixed disk complete.

11.5 Changing an ACG Node Overload Control Level

This procedure is used to change the values of an existing ACG Node Overload Control Level in the database using the chg-acg-noc command.

Refer to Commands User's Guide for complete descriptions of the commands used in the procedure in this section, including parameter names, valid values, rules for using the command correctly, and output examples.

he interval index is the amount of time between ACGs. This is a number that is mapped to a time value at the LNP node. See Table 11-1.

he duration index is the amount of time that the ACG is in effect. This is a number that is mapped to a time value at the LNP node. See Table 11-1.

  1. Display the ACG node overload levels in the database by entering the rtrv-acg-noc command.

    Verify that the ACG NOC level to be changed is in the database.

  2. Change the ACG node overload control level values in the database using the chg-acg-noc command.
  3. Verify the changes using the rtrv-acg-noc command.
  4. Back up the changes using the chg-db:action=backup:dest=fixed command.
    The following messages appear, the active Maintenance and Administration Subsystem Processor (MASP) appears first. 
    
BACKUP (FIXED): MASP A - Backup starts on active MASP.
BACKUP (FIXED): MASP A - Backup on active MASP to fixed disk complete.
BACKUP (FIXED): MASP A - Backup starts on standby MASP.
BACKUP (FIXED): MASP A - Backup on standby MASP to fixed disk complete.

11.6 Adding ACG Manual Initiated Controls

This procedure is used to assign ACG controls to all LNP queries or to specific LNP query services and Called Party digits using the ent-acg-mic command. If the EAGLE query service receives a query to which a control applies, then the EAGLE sends an ACG, encoded as configured, with the response.

Refer to Commands User's Guide for complete descriptions of the commands used in the procedure in this section, including parameter names, valid values, rules for using the command correctly, and output examples..

The duration index is the amount of time that the ACG is in effect. This is a number that is mapped to a time value at the LNP node. See Table 11-1.

The INinterval index is the amount of time between ACGs for IN queries. This is a number that is mapped to a time value at the LNP node. See Table 11-1.

The interval index is the amount of time between for queries. This is a number that is mapped to a time value at the node. See Table 11-1.

Prerequisite for Adding an ACG MIC Control

Before an ACG manual initiated control can be added, the LNP feature must be enabled.
  • Enter the rtrv-ctrl-feat command.
  • If the LNP feature is enabled, the entry LNP ported TNs is shown in the rtrv-ctrl-feat output with a quantity greater than 0.
  • If the LNP feature is not enabled, perform the procedures in the LNP Feature Configuration to enable the LNP feature. Then continue with the procedure in this section.

If the type=all parameter is specified, the nd, intvl, and aintvl parameters must be specified and the serv and dgts parameters cannot be specified. To specify the type=all parameter, no existing ACG manually initiated control specifying all LNP query services can be in the database.

ACG Manually Initiated Control #1

Type of Control = All

Number of Digits = 6

IN Interval Index = 4 - 8 seconds

AIN Interval Index = 7 - 5 seconds

Duration Index = 8 - 128 seconds

ACG Manually Initiated Control #2

Type of Control = SD

Query Service = AIN

AIN Interval Index = 8 - 10 seconds

Digits = 910584

Duration Index = 7 - 64 seconds

ACG Manually Initiated Control #3

Type of Control = SD

Query Service = IN

IN Interval Index = 6 - 16 seconds

Digits = 4237431234

Duration Index = 5 - 16 seconds

  1. Display the manually initiated controls in the database using the rtrv-acg-mic command.

    Verify that the ACG MIC to be added is not already in the database.

  2. Add the ACG manually initiated controls to the database using the ent-acg-mic command.
  3. Verify the changes using the rtrv-acg-mic command with either the type=all parameter, or the parameters and values specified with the type=sd parameter in Step 2.
  4. Back up the changes using the chg-db:action=backup:dest=fixed command.
    The following messages appear, the active Maintenance and Administration Subsystem Processor (MASP) appears first. 
    
BACKUP (FIXED): MASP A - Backup starts on active MASP.
BACKUP (FIXED): MASP A - Backup on active MASP to fixed disk complete.
BACKUP (FIXED): MASP A - Backup starts on standby MASP.
BACKUP (FIXED): MASP A - Backup on standby MASP to fixed disk complete.

11.7 Removing ACG Manual Initiated Controls

This procedure is used to remove an ACG manually initiated control using the dlt-acg-mic command.

Refer to Commands User's Guide for complete descriptions of the commands used in the procedure in this section, including parameter names, valid values, rules for using the command correctly, and output examples.

  1. Display the ACG manually initiated controls in the database using the rtrv-acg-mic command.

    Verify that the ACG MIC to be removed is in the database.

  2. Remove the ACG manually initiated controls from the database using the dlt-acg-mic command.
  3. Verify the changes using the rtrv-acg-mic command with either the type=all parameter, or the parameters and values specified with the type=sd parameter in Step 2.
  4. Back up the changes using the chg-db:action=backup:dest=fixed command.
    The following messages appear, the active Maintenance and Administration Subsystem Processor (MASP) appears first. 
    
BACKUP (FIXED): MASP A - Backup starts on active MASP.
BACKUP (FIXED): MASP A - Backup on active MASP to fixed disk complete.
BACKUP (FIXED): MASP A - Backup starts on standby MASP.
BACKUP (FIXED): MASP A - Backup on standby MASP to fixed disk complete.

11.8 Changing ACG Manual Initiated Controls

This procedure is used to change an existing ACG manually initiated controls using the chg-acg-mic command.

Refer to Commands User's Guide for complete descriptions of the commands used in the procedure in this section, including parameter names, valid values, rules for using the command correctly, and output examples.

The duration index is the amount of time that the ACG is in effect. This is a number that is mapped to a time value at the LNP node. See Table 11-1.

The IN interval index is the amount of time between ACGs for IN queries. This is a number that is mapped to a time value at the LNP node. See Table 11-1.

The AIN interval index – the amount of time between ACGs for AIN queries. This is a number that is mapped to a time value at the LNP node. See Table 11-1.

  1. Display the ACG manually initiated controls in the database using the rtrv-acg-mic command.

    Verify that the ACG MIC that is to be changed is in the database.

  2. Add the ACG manually initiated controls to the database using the chg-acg-mic command.
  3. Verify the changes using the rtrv-acg-mic command with either the type=all parameter, or the serv and dgts parameters and values specified with the type=sd parameter in Step 2.
  4. Back up the changes using the chg-db:action=backup:dest=fixed command.
    The following messages appear, the active Maintenance and Administration Subsystem Processor (MASP) appears first. 
    
BACKUP (FIXED): MASP A - Backup starts on active MASP.
BACKUP (FIXED): MASP A - Backup on active MASP to fixed disk complete.
BACKUP (FIXED): MASP A - Backup starts on standby MASP.
BACKUP (FIXED): MASP A - Backup on standby MASP to fixed disk complete.