3Com NBX 100 Administrator's Manual - page 430
430
A
PPENDIX
D: C
ONNE
X
TIONS
H.323 G
ATEWAY
To perform a gateway loopback test:
1 Access a ConneXtions H.323 port from an NBX Business or Basic
Telephone by dialing an H.323 port line number or by using a dial plan
configured with a ConneXtions pool number.
You must have Super User Group CoS allowed to dial in to a line port
number directly.
2 Enter the IP address of the gateway.
3 Verify the connection. If you are using default settings, you are connected
to the Auto Attendant. If you are not using default settings, you may be
connected to a different extension number.
Local Considerations
All voice packets that move between an NBX Business or Basic Telephone,
Call Processor, ConneXtions gateway, and router on the LAN have a high
priority and high quality of service.
However, at the router and beyond, network administrators can influence
H.323 call quality through the priority that they give to H.323 packets at
both the internet router and at the firewall.If H.323 connections
consistently experience significant delays, you should review the local
router and firewall configurations at each side of the H.323 connection.
Network Checks
A network check uses:
■
Network Ping
■
NetMeeting Connections
Network Ping
A network ping is a packet transfer that checks the logical continuity
between a personal computer and a specified IP (router) address. For
example, you can ping your own address, or the default gateway. The
next ping checks the connection to the IP router at the remote end of the
intended H.323 connection.
The easiest way to initiate a ping is with a DOS ping command. This
command sends four pings to the specified IP address. The router at that
address immediately returns the ping, and the command notes the round
trip delay for each ping packet. Some firewalls do not return pings for
security reasons. If the ping test fails, you can use a “trace router”
command (“tracert”) to find out where the logical connection failed.