Panasonic Kx Tda0490 Getting Started Manual

A1 VoIP Requirements
Getting Started 51
Is there only a single IP network between 2 ends of a call?
A huge degradation in speech quality will be produced when calls are made through multiple IP 
networks as shown below; therefore, it is recommended that you avoid establishing a VoIP network 
in this fashion.
IP Network 1IP Network 2
PSTN
IP Network 1IP Network 2 

A1 VoIP Requirements
52 Getting Started
Is the card located appropriately?
Transmission delays can cause pauses and loss in VoIP communications. The more network devices 
(e.g., routers and switches) there are between the communicating cards, the larger the transmission 
delays, because a certain amount of delay is inevitable when packets go through each network device 
(hop).
One preventative measure is to install the card so that the number of transmission hops is kept to a 
minimum. In the diagram...

A1 VoIP Requirements
Getting Started 53
Are layer 2 or higher switches used?
Use of repeater hubs can increase the network load, and therefore will result in degradation in speech 
quality.
To ensure high speech quality, use only layer 2 or higher switches.
Note
Also note that the port of the switch that connects to the card should be set to operate under 
Auto Negotiation mode. This will help assure error-free communication between the card and 
the switch.
Are Category 5 (CAT5) cables used?
When...

A2 VoIP Requirements Checklist
54 Getting Started
A2 VoIP Requirements Checklist
Use the following checklists to see if you can implement a VoIP network. The answers identified in 
underlined bold-face letters
 are the required answers for the corresponding questions.
Bandwidth Assessment
Network Configuration
No. Question Answer Memo Ref.
1Does the network have enough bandwidth to 
support VoIP communications?
Make sure that there is more bandwidth available 
for VoIP communications than the amount...

A2 VoIP Requirements Checklist
Getting Started 55
Network Devices
QoS (Quality of Service)
No. Question Answer Memo Ref.
3-aCan the firewall pass packets from the VoIP 
Gateway Card?
When a firewall is used, make sure to configure 
the firewall appropriately to allow VoIP packets to 
pass through the network without being blocked 
by filtering. Ye s
 NoModel of the firewall:
p. 52
3-bAre layer 2 or higher switches used?
Do not use repeater hubs as they can increase 
the network load.
Also note that the...

A2 VoIP Requirements Checklist
56 Getting Started 

Getting Started 57
Appendix B
Alternative Numbering Plan Example 

B1 Extension Number Method
58 Getting Started
B1 Extension Number Method
This section provides a numbering plan example using the extension number method, as 
supplementary information to the PBX code method discussed in 1.2.2 Numbering Plan Example.
B1.1 Example Network
The following diagram illustrates a simple VoIP network configured for the extension number method.
PSTN(Public Switched 
Telephone Network)
IP Network
Chicago Office
PSTN Trunk (CO Line) Number: 93
VoIP Gateway Trunk (CO Line) Access...

B1 Extension Number Method
Getting Started 59
B1.2 Numbering Plan Example
IP Addressing Information
The following table is a duplication of the table used for the PBX code method.
PBX Numbering Information
The following table contains VoIP Gateway Trunk (CO Line) Access Number, instead of PBX Code 
and TIE Line Access Number as used in the PBX code method.Los Angeles 
OfficeChicago 
OfficeDescription
Card IP Address  200.45.11.35 199.176.64.41Identifies the location of each VoIP Gateway 
Card in the...

B1 Extension Number Method
60 Getting Started
Dialing Examples
With the extension number method, the caller dials only the destination number of the called party to 
call through PBXs at different locations.
Calling from Los Angeles to Chicago
To extension 301 via VoIP network
To local telephone 123-4567 via VoIP network through local PSTN
Calling from Chicago to Los Angeles
To extension 201 via VoIP network
To local telephone 456-7890 via VoIP network through local PSTN
PBX Connection Information
Los...