4600 Series IP Telephone LAN Administrator’s Guide
Suggestions for Installation and Configuration
2-6
Suggestions for Installation and Configuration 2
Reliability and Performance 2
There is a cost/performance trade-off associated with Voice over IP. Greater reliability and
improved performance can be obtained through server redundancy and components with h igher
bandwidth capabilities.
The reliability and performance of the traditional PBX systems have been very high. Although
much of the LAN is outside of the control of the PBX, there are several points to cons ider which
enhance the reliability and performance of the IP Telephone network.
All 4600 Series IP Telephones support the tools “ping” and “traceroute.” These are standard LAN/
WAN tools for identifying whether two points on a network can communicate with each other, and
what path a sample communication takes as it traverses the network from one point to the othe r.
All 4600 Series IP Telephones will respond appropriately to a ping or a traceroute message sent
from the DEFINITY® or MultiVantage™ switch or any other source on your network, although
these telephones will not, in general, initiate a ping or traceroute. Release 1 .6 of the 4600 Series
IP Telephones introduced “remote ping” and “remote traceroute” support. The switch can instruct
such a 4600 Series IP Telephone to initiate a ping or a traceroute to a specified IP address. The
telephone carries out that instruction and sends a message to the switch informing it of the res ults.
See your DEFINITY® or MultiVantage™ Administration documentation for more details.
As of Release 1.8, if applicable, 4600 Series IP Telephones test whether the network Ethernet
switch port supports IEEE 802.1D/q tagged frames by pinging the router with a tagged frame
(see VLAN Considerations, on page 4-27). If your LAN environment includes Virtual LANs
(VLANs), your router will need to respond to pings to VLAN tagging to work proper ly.
IP Address Lists and Station Number Portability 2
Release 1.5 of the 4600 Series Telephones provided the capability to specify IP address lists (in
either dotted decimal or DNS format) for key elements of the network, rather than mer ely one
address for each. Specifically, you can specify up to 127 total characters in each list of the
following: router/gateways, TFTP servers, and the call server. When the 4600 telephone is
powered up or is rebooted, it attempts to establish communication with these various ne twork
elements in turn, starting with the first address on the respective list. If the communic ation is
denied or times out, the telephone proceeds to the next address on the approp riate list and tries
that one. The telephone does not report failure unless all the addresses on a given list have failed.
Obviously, this capability can significantly improve the reliability of IP telepho ny by maximizing the
likelihood of the telephone communicating with backup equipment if the primary equipment is
down or inaccessible (say, perhaps due to a limited network outage).