User`s guide

Chapter 22 Product Specifications
User’s Guide
225
DHCP DHCP (Dynamic Host Configuration Protocol) allows the individual
clients (computers) to obtain the TCP/IP configuration at start-up from
a centralized DHCP server. Your device has built-in DHCP server
capability enabled by default. It can assign IP addresses, an IP default
gateway and DNS servers to DHCP clients. Your device can also act
as a surrogate DHCP server (DHCP Relay) where it relays IP address
assignment from the actual real DHCP server to the clients.
IP Alias IP alias allows you to partition a physical network into logical networks
over the same Ethernet interface. Your device supports three logical
LAN interfaces via its single physical Ethernet interface with the your
device itself as the gateway for each LAN network.
Multiple SIP Accounts You can configure multiple voice (SIP) accounts.
SIP ALG Your device is a SIP Application Layer Gateway (ALG). It allows VoIP
calls to pass through NAT for devices behind it (such as a SIP-based
VoIP software application on a computer).
Dynamic Jitter Buffer The built-in adaptive buffer helps to smooth out the variations in delay
(jitter) for voice traffic (up to 60 ms). This helps ensure good voice
quality for your conversations.
Voice Activity Detection/
Silence Suppression
Voice Activity Detection (VAD) reduces the bandwidth that a call uses
by not transmitting when you are not speaking.
Comfort Noise Generation Your device generates background noise to fill moments of silence
when the other device in a call stops transmitting because the other
party is not speaking (as total silence could easily be mistaken for a
lost connection).
Echo Cancellation You device supports G.168 of at least 24 ms.
This an ITU-T standard for eliminating the echo caused by the sound
of your voice reverberating in the telephone receiver while you talk.
Time and Date Get the current time and date from an external server when you turn
on your WiMAX Modem. You can also set the time manually.
Logging Use the WiMAX Modem’s logging feature to view connection history,
surveillance logs, and error messages.
Codecs Enhanced Variable Rate Codec (EVRC), G.711 (PCM
µ-law and a-
law), G.729a, and G.723.1
Fax Support T.38 FAX relay (FAX over UDP).
G.711 fax relay for fax calls and be able to renegotiate codec to G.711
if a fax call is detected.
Ring Tones Supports different distinctive ring tones on each line.
Call Prioritization Prioritize VoIP traffic originating from the RJ-11 ports over any other
traffic.
Table 110 Standards Supported
STANDARD DESCRIPTION
RFC 768 User Datagram Protocol
RFC 791 Internet Protocol v4
RFC 792 Internet Control Message Protocol
RFC 792 Transmission Control Protocol
RFC 826 Address Resolution Protocol
RFC 854 Telnet Protocol
Table 109 Firmware Specifications (continued)
FEATURE DESCRIPTION