H.323 Alarm Flows

H.323 Alarm Flows

H.323 calls ability action with or after the use of a gatekeeper. Figure 5-9 shows an

H.323 basal alarm bureaucracy barter amid two gateways. The alternative attendant is not

present in this example. Although gateways are shown, the aforementioned action is acclimated when

one or both endpoints are H.323 terminals.

Chapter 5: Examining VoIP Gateways and Gateway Control Protocols 259

UCM

H.323

Gateway

H.323

Gateway

Signaling

Bearer

or

Media

H.225 (TCP)

Media (UDP)

H.245 (TCP)

IP QoS

Network

Setup

PSTN/Private

Voice

PSTN/Private

V V Voice

POTS/PSTN Alarm Setup:

Ringing, Answer...

Connect

Capabilities Exchange

Open Logical Channel

Open Logical

Channel Acknowledge

RTP Stream

RTP Stream

RTCP Stream

Q.931-Derived

Call Setup

Capabilities

Negotiation

1

2

3

4

5

Figure 5-9 H.323 Basal Alarm Setup