Nortel 2001 Installation And Operation Manual page 395

In Figure 78,
• EndIP = endpoint IP address
• PortID = port ID
• PacketTx = RTP packets sent
• Packet Rx = RTP packets received
• DPacketRx = BTR Disorder packets received
• PacketLossRx = packet loss received xxx%
• JittAveRx = jitter average received xxxxxx
• JittMaxRx = jitter maximum received xxxxxx
• RdTripDelay = round trip delay
Note: Each new call resets the counters.
Network Address Translation (NAT) Traversal
This section describes the Network Address Translation (NAT) Traversal
feature as it effects IP Phones. NAT Traversal is required to permit IP Phones
working behind a NAT box to connect and maintain signaling and media
paths.
NAT Traversal is applicable to all UNIStim IP Phone clients and is
one-ended. That is, it does not require the other end of a call to support any
special protocol, and it is interoperable with any other media termination.
In this document NAT refers to both IP port address mapping and IP address
mapping (also known as NAPT). A NAT can be used with or without a
Virtual Private Network (VPN).
The NAT Traversal feature supports only IP clients behind cone NAT types.
There are three types of cone NAT — the full cone, restricted cone, and the
port restricted cone. NAT traversal is not compatible with symmetric NATs.
If the IP Phone is behind a Symmetric NAT, the LTPS unregisters the phone
from the call server (while remaining registered on the LTPS), and displays
the following message on the IP Phone display: "Error! Symmetric NAT".
Appendix D: IP Phone diagnostic utilities
IP Phones Description, Installation, and Operation
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