Multi-Tech Systems MVP-410ST/810ST IP Phone User Manual


 
MultiVOIP User Guide Overview
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H. 323, SIP, & SPP. Being H.323 compatible, the analog MultiVOIP
unit can place calls to telephone equipment at remote IP network
locations that also contain H.323 compatible voice-over-IP gateways. It
will interface with H.323 software and H.323 gatekeeper units. H.323
specifications also bring to voip telephony many special features
common to conventional telephony. H.323 features of this kind that
have been implemented into the MultiVOIP include Call Hold, Call
Waiting, Call Identification, Call Forwarding (from the H.450 standard),
and Call Transfer (H.450.2 from H.323 Version 2). The fourth version of
the H.323 standard improves system resource usage (esp. logical port or
socket usage) by handling call signaling more compactly and allowing
use of the low-overhead UDP protocol instead of the error-correcting
TCP protocol where possible.
The MultiVOIP is also SIP-compatible. (“SIP” means Session Initiation
Protocol.) However, H.450 Supplementary Services features can be
used under H.323 only and not under SIP.
SPP (Single-Port Protocol) is a non-standard protocol developed by
Multi-Tech. SPP is not compatible with the “Proprietary” protocol used
in Multi-Tech’s earlier generation of voip gateways. SPP offers
advantages in certain situations, especially when firewalls are used and
when dynamic IP address assignment is needed. However, when SPP
is used, certain features of SIP and H.323 will not be available and SPP
will not inter-operate with voip systems using H.323 or SIP.
Data Compression & Quality of Service. The analog MultiVOIP unit
comes equipped with a variety of data compression capabilities,
including G.723, G.729, and G.711 and features DiffServ quality-of-
service (QoS) capabilities.
PSTN Failover Feature. The MultiVOIP can be programmed to divert
calls to the PSTN temporarily in case the IP network fails.
Gatekeepers. For voip systems built with MultiTech’s analog gateway
units, users can have a stand-alone gatekeeper (gatekeeper software
residing in separate hardware). Gatekeepers are optional but useful
within voip systems. The gatekeeper acts as the ‘clearinghouse’ for all
calls within its zone. MultiTech’s stand-alone gatekeeper software
performs all of the standard gatekeepers functions (address translation,
admission control, and bandwidth control) and also supports many
valuable optional functions (call control signaling, call authorization,
bandwidth management, and call management).