Polycom 4300T - Manual (Page 21)

Configuring the 4300T
3 - 3
• NAT/PAT translation for IP phones and PC’s. This allows a single public
IP address to be used on the WAN link to represent all of the private IP
addresses assigned to the LAN IP phones and PC’s.
• Static NAT entries. This enables the customer to use a WAN public IP
address for data servers (web, mail, ftp, etc.) connected behind the 4300T.
These servers can then be configured with private IP addresses for
additional security.
• A “VoIP” aware firewall. A full Layer 7 gateway for voice traffic and a
stateful packet inspection firewall for data traffic.
• Call Admission Control (CAC). CAC uses a deterministic algorithm to
decide when there are insufficient network resources available to
adequately support new calls and then return the equivalent of a “fast
busy” to new call requests.
• DHCP server and TFTP relay. These features are used to simplify and
expedite the IP configuration of phones and PC’s. This also includes VoIP
signaling gateway information (MGCP, SIP, H.323 and SCCP).
• Call quality monitoring (using MOS, jitter, latency, packet loss and much
more) and test tools.
• VoIP survivability. Provides call switching to an LAN based PSTN
gateway during WAN outages.
Configuration Outline
Task Subtask
Configure For IP Centrex
Application?
System Configuration configure LAN/WAN interface Yes
set ethernet link rate Optional
enable the DHCP server Optional but recommended
configure SNMP Optional
VoIP Configuration enable the VoIP ALG Yes
configure a VoIP subnet route Optional
Data Networking Configuration dynamic NAT Optional but recommended
static NAT Optional
static IP routing Optional
Firewall Configuration enable the data firewall Yes
configure basic settings Optional
configure advanced settings Optional