The Cisco® High-Density Analog and Digital Extension Module for Voice and Fax (EVM-HD) provides enterprises, managed service providers, and service providers the ability to directly connect public-switched telephone networks (PSTNs) and existing telephony equipment to Cisco 2821, 2851, 3825, and 3845 Integrated Services Routers (ISRs). With support for up to 24 total voice and fax sessions, the Cisco EVM-HD is ideal for networks with high analog (foreign exchange station [FXS], direct inward dialing [DID], and foreign exchange office [FXO]) and digital (Basic Rate Interface [BRI]) call-capacity requirements.
Product Overview
The Cisco EVM-HD is an industry-leading voice and fax interface module for Cisco 2821, 2851, 3825, and 3845 ISRs. It helps enable packet voice technologies with support for voice over IP (VoIP), including H.323, Media Gateway Control Protocol (MGCP) and Session Initiation Protocol (SIP); voice over Frame Relay (VoFR), and voice over ATM (VoATM), including ATM Adaptation Layer 2 (AAL2) and AAL5. The Cisco EVM-HD allows Cisco 2821, 2851, 3825, and 3845 ISRs to connect directly to the PSTN and existing telephony equipment (for example, private branch exchange [PBX], key system, analog telephones, and analog fax machines) through standard analog (FXS, DID, and FXO) and digital (BRI) interfaces. The Cisco EVM-HD supports telephony toll bypass, new packet telephony applications, and full gateway integration within the Cisco Unified Communications. IP telephony design. With support for up to 24 total voice and fax sessions, the Cisco EVM-HD is ideal for networks with high analog and BRI call-capacity requirements; refer to Figure 1.
Figure 1. Cisco EVM-HD
The Cisco EVM-HD includes the following components:
• An 8-port expansion module supporting 8 ports that can be individually configured for FXS or DID signaling-see below for restrictions
• Voice and fax expansion modules:
– A 4-port expansion module supporting BRI (NT and TE) (part number EM-4BRI-NT/TE)
– An 8-port expansion module supporting FXS (part number EM3-HDA-8FXS/DID)
– A 6-port expansion module supporting FXO (part number EM-HDA-6FXO)
– A 7-port expansion module with 3 FXS and 4 FXO ports (part number EM-HDA-3FXS/4FXO)
Adding expansion modules to the Cisco EVM-HD baseboard increases voice and fax session capacity. The modular design of the Cisco EVM-HD provides maximum flexibility: plug in up to two expansion modules in any combination to build the Cisco EVM-HD best suited for specific packet telephony network locations. The Cisco EVM-HD provides gateway services for Cisco AVVID using Cisco CallManager with Survivable Remote Site Telephony (SRST) or Cisco CallManager Express (CME). Gateway services allow users to deploy networks that take advantage of investments in existing telephony equipment while also deploying and integrating IP telephony. The network can operate at any point on the voice, video, and integrated data spectrum with the ability to add connections for both traditional telephony devices and IP telephony endpoints.
Cisco 2821 and 2851 ISR Extension Voice Module Slot
The Cisco EVM-HD operates in the extension voice module (EVM) slot on the Cisco 2821 and 2851 ISRs. The EVM slot supports additional voice services and density without consuming the network module slot on the Cisco 2821 or 2851 ISR.
Cisco 3825 and 3845 Network Module Slot
The Cisco EVM-HD operates in any network module or enhanced network module (NME) slot on the Cisco 3825 and 3845 ISRs. The Cisco 3825 supports one Cisco EVM-HD, and the Cisco 3845 supports one or two Cisco EVM-HDs.
Cisco EVM-HD Digital Signal Processor Resources
Packet voice digital signal processor (DSP) modules (PVDM2s) are used in combination with the Cisco EVM-HD baseboard and its expansion modules. PVDM2s support multiple voice codecs, fax, conferencing, and transcoding services. PVDM2s are purchased separately and installed in the DSP module slots located inside the Cisco 2821, 2851, 3825, and Cisco 3845 ISRs. Initial orders for a Cisco 2821, 2851, 3825, or 3845 ISR that include a Cisco EVM-HD should also include an appropriate number of PVDM2s.
Applications
Table 1 lists the Cisco EVM-HD and expansion modules available and the applications each supports.
Table 1. Cisco EVM-HD Baseboard and Expansion Modules
Product Number
Description
EVM-HD-8FXS/DID
The Cisco EVM-HD for voice and fax has 8 FXS and DID ports. Individual ports on the baseboard module can be configured for FXS or DID signaling. Adjacent ports should share the same configuration to avoid impedance setting conflicts. A change to the impedance setting for one port changes the setting on the adjacent port. Paired ports are: 0 and 1; 2 and 3; 4 and 5; 6 and 7. An on-premises FXS interface connects directly to a standard telephone, fax machine or similar device and supplies ring, voltage, and dial tone. Signaling support available in FXS mode includes loop-start and ground-start. DID trunks from the central office can be connected to the Cisco EVM-HD baseboard for off-premises connections. Signaling support available in DID mode includes immediate, delay dial, and wink start. Users plug in up to two expansion modules in any combination to increase the voice and fax capacity of the Cisco EVM-HD baseboard.
EM-4BRI-NT/TE
This 4-port BRI voice and fax expansion module has ports that are configurable for NT or TE mode. This module allows connection to an ISDN S/T network by replicating either the network side or the terminal side. In NT mode the ports replicate the PSTN interface to a PBX that is compatible with European Telecommunications Standards Institute (ETSI) NET3 and QSIG switch types. In TE mode the ports support the same ISDN protocols as other Cisco products to allow connection to ISDN S/T networks, or through an external NT1 to ISDN U-interfaces. This module provides four on-premises S/T BRI trunk connections to the ISDN PBX.
EM3-HDA-8FXS/DID
This 8-port FXS/DID voice and fax expansion module has 8 FXS and DID ports, individually configurable for FXS or DID signaling. There is no requirement for signaling type pairing of adjacent ports for this module. The FXS interface connect directly to a standard telephone, fax machine or similar device and supplies ring, voltage, and dial tone. Signaling support available in FXS mode includes loop-start and ground-start. DID trunks from the central office can be connected for off-premise Direct Inward Dial connections. Signaling support available in DID mode includes immediate, delay dial, and wink start. A maximum of 8 ports configured as DID are supported in both EVM expansion module slots combined. Thus, a maximum 16 DID ports per EVM capable ISR slot can be supported when 8 ports of EVM-HD-8FXS/DID and 8 ports of EM3-HDA-8FXS/DID are all configured as DID.
EM-HDA-6FXO
This 6-port FXO voice and fax expansion module provides off-premises connection to the central office. This module supports FXO power failover. If power to the router fails, this feature helps enable a direct metallic path between an FXO port and a special "red." It also supports analog Centralized Automated Message Accounting (CAMA) on any port. Telephone to provide a direct line to the PSTN.
EM-HDA-3FXS/4FXO
This 3-port FXS and 4-port FXO voice and fax expansion module provides on-premises FXS signaling to connect directly to a standard telephone, fax machine, or similar device and supplies ring, voltage, and dial tone. In addition, the FXO ports provide off-premises connection to the central office. FXS signaling support available includes loop-start and ground-start. There is no DID support. In addition, there is no FXO power failover support on the FXO ports. It also supports analog CAMA on any port.
Note: EM3-HDA-8FXS/DID is NOT supported on NM-HDA-4FXS
Table 2 gives the DSP resources for the Cisco EVM-HD for voice and fax.
Table 2. DSP Resources for the Cisco EVM-HD
Module
Description
PVDM2-8
PVDM2 modules provide central DSP resources for the Cisco EVM-HD baseboard and its expansion modules. PVDM2 modules are purchased separately and installed in the DSP module slots located inside the Cisco 2821, 2851, 3825, and 3845 ISRs.
Table 3 lists the call complexity and codecs supported with PVDM2s.
Table 3. Call Complexity and Codecs Supported with PVDM2 DSP Modules
Call Complexity
Standard Codecs Supported
High Complexity
G.711 a-law and mu-law; G.726 @ 32k, 24k, and 16k; G.729, A, B and AB; G.723.1 @ 5.3k and 6.3k; G.728, GSMFR, GSMEFR, clear channel codec, and fax relay
Medium Complexity
G.711 a-law and mu-law; G.726 @ 32k, 24k, and 16k; G.729A and AB; clear channel codec, and fax relay
Flexible or Low Complexity
G.711 a-law and mu-law
Primary Features and Benefits
Table 4 summarizes the features and benefits of the Cisco EVM-HD.
Table 4. Cisco EVM-HD Features and Benefits Summary
Feature
Benefit
Voice and Fax Over IP
Voice and fax traffic is transport independent because IP traffic at Layer 3 can travel over any Layer 1 or Layer 2 media, including ISDN, leased lines, serial connections, Frame Relay, Ethernet, Token Ring, and ATM.
Voice and Fax Over Frame Relay
Applications requiring voice and fax traffic to be routed directly over Frame Relay networks will take advantage of FRF.11 and FRF.12 VoFR and fragmentation standards. This solution also uses features found only in Cisco IOS® Software for maintaining voice quality.
VoATM
Voice is transported directly over ATM networks using AAL2 or AAL5 encapsulation to take advantage of existing ATM networks as a direct transport method for voice. VoIP also can be transported over ATM.
Connection Trunk
The connection trunk creates a tie-line replacement structure while only consuming bandwidth during a call (digital-to-digital, digital-to-analog, or analog-to-analog capabilities).
Local Voice Busy-Out (LVBO)
Users can automatically busy-out any desired voice trunk line to a PBX or PSTN when a direct WAN or LAN connection to the router is down. This feature also allows busy-out of a far end trunk connection when configured for connection trunk.
Caller-ID Support
The module offers per-port configurable caller ID to phones connected to analog FXS voice ports using per call unblocking if desired. It interoperates with analog phones, the PSTN, PBXs, Cisco CallManager, Cisco CME, and H.323 terminals such as Microsoft NetMeeting and IP phones.
Call Admission Control Using Response Time Reporter (RTR)
This product uses RTR to determine latency, delay, and jitter and to provide real-time Impairment/Calculated Impairment Planning Factor (ICPIF) calculations before establishing a call across an IP infrastructure. RTR packets emulate voice packets, receiving the same priority as voice throughout the network. This is a superior method to data and ping packets for determining congestion levels.
Voice and Fax Over The Same Port
Ports can be used for both voice and fax traffic; no dedicated ports are required.
Works with Existing Phones, Faxes, PBXs, and Key Systems
No user retraining is required.
Call Control Signaling
The product supports H.323 Versions 1, 2, 3, and 4; MGCP Version 0.1 and 1.0, and SIP call control protocols. The Cisco EVM-HD interoperates with any Cisco CallManager release using the H.323 protocol. For MGCP, Cisco CallManager Release 3.3(5), Release 4.0(2), and Release 4.1 add support for the Cisco EVM-HD. Support is also available with Cisco CME Release 3.1. Cisco voice and fax modules are interoperable with numerous emerging voice and videoconferencing applications.
High-Performance DSP Architecture
PVDM2 modules used in combination with the Cisco EVM-HD baseboard and its expansion modules offer extremely low latency, which is essential for high-quality voice and fax services; the DSP architecture also helps enable all critical functions to be handled in software, allowing for simple code updates, scalability, and new features. PVDM2s feature the latest DSP technology with support for conferencing and transcoding, higher call densities per DSP, and more flexibility in channel allocation per DSP.
ITU Standard Codecs Such as G.729, G.729A/B, and G.711
These standards-based compression technologies allow transmission of voice across IP, Frame Relay, and ATM. G.711 is standard 64-kbps PCM modulation using either mu-law or a-law. For a complete list of codecs supported, refer to Table 3.
Silence Suppression and Voice Activity Detection
Bandwidth is used only when someone is speaking. During silent periods of a phone call (approximately 50 percent of the time), bandwidth is available for other traffic.
Comfort Noise Generation
To better simulate phone calls over voice networks, this feature reassures the phone user that the connection is being maintained, even when no voice packets are being transmitted.
Dial-Plan Mapping
Automatic mapping of dialed VoIP phone numbers to IP addresses simplifies configuration and management.
Dual-Tone Multifrequency (DTMF) Tone Processing
This feature helps enable access to voicemail and interactive-voice-response (IVR) systems.
Fax and Modem Pass-Through
This feature allows fax and modem traffic to pass through a voice port.
Fax Relay
Fax relay provides a more robust protocol for fax transmission over packet networks. It includes support for T.38 and T.37 fax protocols.
Country-Specific Signaling
This feature transparently delivers customary phone signals to users, facilitating acceptance of new technology.
Autocalling and Private-Line Automatic Ring-Down (PLAR)
With this feature, a destination phone can be configured to automatically ring when the caller lifts the handset.
Hunt Groups
Calls can be forwarded automatically to the first available line.
Battery Polarity Reversal Detection and Initiation
Detection of disconnect supervision and far-end answer supervision through battery polarity reversal provides a robust method of providing supervisory disconnect, especially for loop start signaling on FXS and FXO interfaces.
Supervisory Disconnect .
Signaling protocols such as loop start do not provide means for quickly detecting when the call initiation is terminated prior to call connection. Supervisory disconnect quickly makes this determination and frees valuable resources for other calls.
Product Specifications
Table 5 gives specifications of the 8-port FXS and DID High-Density Extension Module baseboard.
Table 5. Specifications of 8-Port FXS and DID Voice and Fax Extension Module Baseboard
Product
Specifications
Part Number
EVM-HD-8FXS/DID
Software Compatibility
Cisco IOS Software Release 12.3(8)T4 or later
Memory Requirements
Refer to the Cisco IOS Software release notes to determine minimum Flash and system memory requirements.
EMC Compliance
FCC Class A device, CE Class A
Safety Conformance
UL 60950, EN 60950, AS/NZS60950, IEC 60950
Network Equipment Building System (NEBS) Compliance
• Designed for NEBS Level 3: GR-63 and GR-1089, Type 1/3.
• Formal NEBS certification testing in progress; compliance results will be published upon completion
Physical Connector
One RJ-21 connector
RJ-21 Distribution Panel
• MENTION OF NON-CISCO PRODUCTS OR SERVICES IS FOR INFORMATION PURPOSES ONLY AND CONSTITUTES NEITHER AN ENDORSEMENT NOR A RECOMMENDATION.
• Distribution panels are generally available from multiple cable and network adapter vendors. Customers may, at their sole discretion, consider using a patch panel from Black Box Corporation. The Black Box patch panel accommodates RJ-11 and RJ-45 combinations and offers flexibility for expansion module upgrades (analog or digital). The Black Box patch panel is available direct from the manufacturer or from several national resellers and distributors.
• Black Box Corporation: http://blackbox.com/
• Technical support and ordering: 724 746-5500
• Black Box part number: JPM2194A
• Description: Distribution Panel for EVM-HD
Spare
The spare part number is EVM-HD-8FXS/DID=.
Expansion Modules
The Cisco EVM-HD baseboard supports 0, 1, or 2 expansion modules in any combination
DSP Resources
PVDM2s provide central DSP resources for the Cisco EVM-HD baseboard and its expansion modules. PVDM2s are purchased separately and installed in the DSP module slots located inside the Cisco 2821, 2851, 3825, and 3845 ISRs.
DID Signaling Modes
Immediate, delay-dial, and wink start
DID Loop Resistance
Up to 1800 ohms (including the terminal equipment)
Disconnect Supervision
Power denial (calling-party control, far-end disconnect)
Caller ID
On-hook transmission of frequency-shift-keying data
FXS Loop Resistance
Up to 600 ohms (including the phone or terminal equipment)
On-Hook Voltage
-43V
Ringing Tone
The ringing tone is configurable for different country requirements
Ringing Voltage
40 Vrms at 5 REN at 25 Hz (configurable frequency)
