Datasheet

Data Sheet
© 2009 Cisco Systems, Inc. All rights reserved. This document is Cisco Public Information. Page 4 of 12
Table 2. Number of Cisco IP Communications Voice/Fax Network Modules Allowed per Cisco Platform
Cisco Platform Maximum Number of Network Modules Allowed
Cisco 2811/2821/2851 Integrated Services Routers 1
Cisco 3825 Integrated Services Router 2
Cisco 3845 Integrated Services Router 4
Cisco 2901/2911/2921/2951 Integrated Services Routers 0 / 1 / 1 / 2
Cisco 3925/3945 Integrated Services Routers 2 / 4
Table 3 summarizes the features and benefits of Cisco IP Communications voice/fax network modules.
Table 3. Features and Benefits
Feature Description and Benefits
IP Telephony Unified communications
●
Integrates all Cisco IP Communications solutions by providing flexible and reliable
connectivity to public or private switched telephone networks around the world.
●
Provides gateway for Cisco IP phones to PSTN or traditional PBXs and private automatic
branch exchanges (PABXs).
●
Provides gateway to PSTN for traditional PBXs, phones, fax machines, and key communication
systems connected to a voice, data, and video infrastructure.
Toll Bypass
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Reduce or eliminate toll charges assessed by long distance and local carriers by transporting
voice and fax traffic across the enterprise intranet, LAN, metropolitan-area network (MAN), or
WAN.
●
Works with existing phones, faxes, PBXs, and key systems.
●
Connection trunks creates a permanent tie-line replacement structure (digital-to-digital, digital-
to-analog, or analog-to-analog capabilities).
●
Interoperates end-to-end with Cisco IP phones, analog phones, fax machine connections, and
PBX or PABX connections to and from other Cisco voice enabled products.
Voice over Packet Transport
●
Voice/Fax over IP—VoIP traffic at Layer 3 can travel over any Layer 1 or Layer 2 media,
including ISDN, leased lines, serial connections, and Ethernet.
●
Compressed Real-Time Protocol (cRTP) offers RTP header compression and packet
fragmentation techniques that allow toll-quality voice and fax transmissions over any WAN
connection.
●
Call Admission Control and PSTN Fallback uses Service Assurance Agent (SAA) to
determine latency, delay and jitter and provide real-time Calculated Planning Impairment Factor
(ICPIF) calculations before establishing a call across an IP infrastructure. SAA packets emulate
voice packets receiving the same priority as voice throughout the entire network.
●
Advanced QoS Mechanisms—These configurable Cisco IOS Software features reserve
appropriate bandwidth and prioritize voice and fax traffic to help ensure transparent delivery
of toll-quality voice and fax. They include Resource Reservation Protocol (RSVP), queuing
techniques (such as Low Latency Queuing), IP Precedence, and differentiated services code
points (DSCPs).
Call Control Signaling Supports H.323 V1/V2/V3/V4, MGCP 0.1/1.0, and SIP call control protocols. Also supports Cisco
UCM using MGCP, H.323, or SIP.
International Telecommunications Union
(ITU) Standard Voice Codecs
G.711, G.729, G.729a/b, G.723.1, G.726, G.728, iLBC, G.722—These are standards-based
compression technologies allowing transmission of voice across IP.
Telephony Interface Signaling Support Supports the following signaling protocols:
●
FXO/FXS loop-start and ground-start signaling
●
E&M (wink, immediate, delay)
●
Inbound signaling (such as dual-tone multifrequency [DTMF], multifrequency support)
●
T1 and E1 channel associated signaling (CAS)
●
T1 and E1 PRI Q.931 user side and network side
●
T1 and E1 PRI QSIG
●
E1 MelCAS
●
E1 R2 CAS
●
T1 and E1 Transparent common channel signaling (CCS) (with multiple-D channel)
●
Country-specific signaling
Voice Features
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Echo Cancellation—Cancels echo on tail circuits up to 32 msec (configurable tail length)
●
Silence Suppression, Voice Activity Detection (VAD)—Bandwidth is used only when
someone is speaking. During silent periods of a phone call, bandwidth is available for data traffic.
●
Comfort Noise Generation—This feature reassures the phone user that the connection is being
maintained, even when no voice packets are being transmitted