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Call Agent Reconnect

Purpose

In general, scenarios like the one below require call agent to reconnect calls.

A and B are SIP endpoints. C could be an IP/PSTN channel or a DSP resource playing an announcement.

1. A and B are connected in bearer-free mode.

2. B is put on hold.

3. A gets connected to C in bearer mode.

4. C is released.

5. A get reconnected to B.

This section explains two specific reconnect scenarios supported by the CSP. Each scenario includes a call flow and message trace.

Using Third Party Integrated Voice Recognition Equipment

The following call flow assumes endpoints A and B are already connected in bearer-free mode.

Message Trace

Initial State

[0x1004 (4100)] (07,04) <--> [0x1003 (4099)] (07,03) 2-Way Connect (Endpoint A)

[0x1003 (4099)] (07,03) <--> [0x1004 (4100)] (07,04) 2-Way Connect (Endpoint B)

1. Route Control message to Endpoint C (Bearer ON)

H->X

[00 81 00 e8 00 05 ff 00 01 29 02 ff fe 02 03 00 1e 00 19 00 04 00 13 00 02 00 08 00 08 00 02 00 65 00 0f 00

01 0b 00 65 00 02 00 00 03 00 33 00 52 00 09 27 7e 00 03 08 01 00 29 37 00 01 00 29 38 00 07 6c 75 63 65 6e

74 00 29 19 00 05 33 33 33 33 00 29 1b 00 0c 31 30 2e 31 30 2e 36 35 2e 33 37 00 29 24 00 05 33 36 33 38 00

29 3a 00 05 31 32 33 34 00 29 3c 00 05 31 32 33 34 00 29 14 00 01 00]

X->H

[00 14 00 e8 00 05 ff 00 10 01 02 1e 09 00 01 00 39 00 03 00 01 07]

2. Park A-B

H->X

[00 11 00 bf 00 03 ff 00 02 0d 03 00 07 03 0d 03 00 07 04]

X->H [00 07 00 bf 00 03 ff 00 10]

Resulting Channel State

[0x1003 (4099)] (07,03) <-- IDLE, L4 STATE 7

[0x1004 (4100)] (07,04) <-- IDLE, L4 STATE 7

3. Put B on Hold (optional)

H->X

[00 1d 00 44 00 04 ff 00 01 0d 03 00 07 04 00 a7 00 1e 01 03 00 33 00 07 00 01 27 b3 00 01 03]

X->H [00 07 00 44 00 04 ff 00 10]

Resulting Channel State

[0x1003 (4099)] (07,03) <-- IDLE, L4 STATE 7

[0x1004 (4100)] (07,04) <-- IDLE, L4 STATE 7

4. Connecting A to C

H->X

[00 11 00 00 00 06 ff 00 02 0d 03 00 07 03 0d 03 00 01 07]

X->H [00 07 00 00 00 06 ff 00 10]

Resulting Channel State

[0x1003 (4099)] (07,03) <--> [0x25f (0607)] (01,07) 2-Way Connect

[0x1004 (4100)] (07,04) <-- IDLE, L4 STATE 7

[0x25f (0607)] (01,07) <--> [0x287 (0647)] (01,08) 2-Way Connect

[0x287 (0647)] (01,08) <--> [0x25f (0607)] (01,07) 2-Way Connect

5. Releasing C

H->X

[00 11 00 08 00 07 ff 00 02 0d 03 00 01 07 0d 03 00 01 07]

X->H [00 07 00 08 00 07 ff 00 10]

X->H

[00 57 00 69 00 11 ff 00 01 0d 03 00 01 07 02 02 1e 2a 00 05 01 04 00 04 ff ff ff ff 01 05 00 04 00 00 05 e9 01 11 00 04 00 00 05 ee 01 10 00 04 00 03 b1 a0 01 12 00 04 00 03 b4 c0 03 00 33 00 18 00 03 27 4e 00 02 00 10 27 92 00 04 0a 0a 41 65 27 93 00 04 00 00 28 bc]

H->X [00 05 00 69 00 11 ff]

Channel A is parked by L4

X->H [00 0e 00 42 00 3b ff 00 01 0d 03 00 07 03 04 00]

H->X [00 05 00 42 00 3b ff]

Resulting Channel State

[0x1003 (4099)] (07,03) <-- IDLE, L4 STATE 7

[0x1004 (4100)] (07,04) <-- IDLE, L4 STATE 7

6. Reconnecting A to B

H->X

[00 4e 00 05 00 08 ff 00 02 0d 03 00 07 03 0d 03 00 07 04 01 02 03 00 1e 00 08 00 01 01 16 00 02 00 01 03 00 33 00 29 00 01 2a 00 00 23 2a 0e 00 04 0a 0a 41 87 2a 01 00 17 2a 03 00 01 00 2a 07 00 04 00 00 14 f8 2a 02 00 06 2a 08 00 02 00 02]

X->H [00 07 00 05 00 08 ff 00 10]

Resulting Channel State (Same as initial state)

[0x1003 (4099)] (07,03) <--> [0x1004 (4100)] (07,04) 2-Way Connect

[0x1004 (4100)] (07,04) <--> [0x1003 (4099)] (07,03) 2-Way Connect

7. Putting B on 2 way voice path (un hold)

H->X

[00 1d 00 44 00 09 ff 00 01 0d 03 00 07 04 00 a7 00 1e 01 03 00 33 00 07 00 01 27 b3 00 01 00]

X->H [00 07 00 44 00 00 ff 00 10]

Using DSP Card

In the following call flow there is no third party equipment involved for playing announcements or collecting digits. The CSP uses the resources on the DSP card instead.

Message Trace

Recorded Announcement Connect message (0x0055)

H->X

[00 23 00 55 00 00 01 00 01 0d 03 00 01 00 00 03 0a 02 16 02 17 02 18 02 16 02 16 02 16 02 16 02 16 02 16 02 17]

Session-Initiation Protocol. A signaling protocol used for establishing sessions in an IP network. A session could be a simple, two-way telephone call, or it could be a collaborative multi-media conference session.
Internet Protocol. Part of the TCP/IP family of protocols used to route messages and tracks the addresses of nodes.
Public Switched Telephone Network
Digital Signal Processor
The condition of a component at a given instant. The current "context" of a PPL object, such as Idle, Seizing, Answered. In PPL files, a State is represented by a circle.
An H.323 terminal or gateway, or MCU. An endpoint can call and be called. It generates and/or terminates the information stream.