3 Control questions

3.1 What is the Centrex group, what is the difference from business group and complex group? 3.2 What is the principle of establishing a connection when calling between subscribers of the Centrex and external calls? 3.3 What types of calls can the Centrex subscriber establish? 3.4 Which stages includes the algorithm of the Centrex group creation?

4 Home task

4.1 Give written answers to test questions. 4.2 To familiarize with the principle of the Centrex administration services.

5 Lab task

5.1 Identify the principles of the Centrex administration in Management Node. 5.2 Review existing Centrex groups at switching nodes of the network, pay attention to the organization principles.

5.3 Get acquainted with the numbering range, created on the node, select phone numbers for the new Centrex group. 5.4 Identify the prefix for calls outside the Centrex group. 5.5 Identify short numbers to be used inside the group. 5.6 Perform administration of the Centrex group, using prepared in points 5.2-5.4 parameters with the use of general administration algorithm in Fig. 11.2.

Alpha

6 Report contents

6.1 The answers to test questions 3.1-3.4. 6.2 The sequence of procedures for administering the Centrex. 6.3 Results of the service testing 6.4 Conclusions.

Laboratory work №11

Groups of serial lines

1 Objectives

To study possibilities of groups of serial lines. Consider how to create a group, opportunity of groups management.

2 Main positions

2.1 Overview. The SI2000 provides the organization of groups of serial lines (multichannel phones). The service allows a subscriber to connect to one of the members of a of free PBX group by using the main number. The PBX group consists of subscribers with a common calling number - as the main number can be used an individual number or subscriber number of a member of the group. PBX group members can be subscribers of one switching and access node or subscribers of another node. The members of the group also have their own subscriber numbers to receive their own calls.

For the administration of the groups of serial lines, you have to perform next actions:

1. To write all necessary subscriber numbers in a group of serial numbers. Table CMG, menu Subscriber->Subscriber Group. Settings:

• Group - defines the group number to which to write the subscriber number. The same user can be switched simultaneously in several different groups. • Sequence Number - shows the serial subscriber number in the group. • Directory Number - determines the subscriber number, which is written to the group.

2. Describe created group of serial lines. Use the CMG table, menu Subscriber-> Line Hunting. Options: • Group determines the number of described group of serial lines. (create in step 1). • Basic Service - defines the basic services that are allowed for the participants of the described group. Must coincide with the main service permitted to the principle number of

group of serial lines. • Feature Type - determines the type of group of serial lines. The values ​​are: • PBX - a group of serial lines. When you call the main number of the serial line the search of the free area (subscriber) of this group is carried out. If all lines are busy or off disabled, then the call is rejected.

1. PBX with Queue - a group of serial lines with the queue. When you call the main number of the group of serial line, the search for free member (subscriber) of this group is held. If all lines are busy or are disabled, the call is set to wait for the release of a free line in the group.

• Group Call - a group of serial lines with a total acceptation of the call. When you call to the main number of group, "CALL" is sent to all subscribers,  the user who picked up handset first – receives the call.

• Hunting Method - defines a method for finding a free line in the group. It may take the following values​​: a) Cyclic - search free line in a circle. Provides a uniform load on all members of the group; b) Linear - search for free line in the group by members’ number in ascending sequence are always starting from the first.

• Calling Type -determines the time of sending the signal  "Call" to the free member of the group  before switching to the next available member. • Queue Length - is only meaningful for a group of serial lines with the queue. It determines the maximum number of subscribers that are waiting for the release of member of the group. • Destination DN determines the subscriber number, to which all calls of the group will be redirected, if all members of the group enabled the service "a temporary ban on incoming calls."

3. Identify the main number of described group of a serial lines. The main number can be among the group members or not, a member may be connected to any subscriber access or not. The basic service that is permitted  to the main number must necessarily coincide with the main service allowed to the entire group of serial lines. Use the table of CMG, Subscriber-> Subscriber. Find the subscriber number, which we want to make a main number of serial lines, Update, tab Group.

In opened window in the field Group we must insert the number of group of serial lines and put a flag Activity (in the field Feature will appear the type of given group of serial lines).

3 Control questions

3.1 What advantages of the group of serial line?

3.2 What regimes of search of lines are available in the group?

3.3 How will lines, coming to the group be identified at outgoing calls?

4 Home task

4.1 Give written answers to the control questions.

4.2 Get familiar with management of groups of serial lines principles.

5 Lab task

5.1 Get familiar with already existing groups on the node.

5.2 Define the numbers for new group. Create a new group, include all chosen numbers.

5.3 Describe parameters of the created group.

5.4 Define main (pilot) group number.

5.5 To test groups’ work, by carrying out few incoming calls on the main number of the group.

6 Report contents

6.1 Answers to the control questions. 3.1-3.4

6.2 Sequence of procedures for management of group of serial lines.

6.3 Results of groups’ work testing.

6.4 Conclusions.