Cisco 2901 User Manual

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Cisco 3900 Series, Cisco 2900 Series, and Cisco 1900 Series Integrated Services Routers Generation 2 Software Configuration Guide
Chapter Unified Communications on Cisco Integrated Services Routers
Call Control
A Cisco Unified CME system is extremely flexible because it is modular. A Cisco Unified CME system
consists of a router that serves as a gateway and one or more VLANs that connect IP phones and phone
devices to the router.
See Cisco Unified Communications Manager Express (CME) Overview at:
http://www.cisco.com/en/US/docs/voice_ip_comm/cucme/admin/configuration/guide/cmeover.html.
Unified Survivable Remote Site Telephony
Cisco Unified Survivable Remote Site Telephony (SRST) enables Cisco routers to provide call-handling
support for Cisco IP phones when they lose connection to Cisco Unified Communications Manager
(CUCM) installations, or when the WAN connection is down. In a centralized deployment, under normal
conditions, Cisco IP phones are controlled by the Cisco Unified Communications Manager located at a
central site like the headquarters of an enterprise. When connection to CUCM breaks, for example as
result of a failure in the network, Unified SRST automatically detects the failure and auto configures the
router for providing backup call processing functionality.
During a WAN failure, the router allows all the phones to re-register to the remote site router in SRST
mode, allowing all inbound and outbound dialing to be routed off to the PSTN (on a backup Foreign
Exchange Office (FXO), BRI or Primary Rate Interface (PRI) connection).
Unified SRST provides redundancy for both Cisco IP as well as Analog phones to ensure that the
telephone system remains operational during network failures. Both Skinny Client Control Protocol
(SCCP) and session initiation protocol (SIP) based Cisco IP phones are supported with the Unified
SRST.
When the WAN link or connection to the Cisco Unified Communications Manager is restored, call
handling reverts back to the Cisco Unified Communications Manager automatically without need for any
human intervention.
For general Unified SRST information, see Cisco Unified SRST System Administrator Guide.
• For information on how the H.323 and Media Gateway Control Protocol (MGCP) call control
protocols relate to SRST, see Cisco Unified SRST System Administrator Guide:
– For H.323, see H.323 Gateways and SRST at Cisco.com.
– For MGCP, see MGCP Gateways and SRST at Cisco.com.
• Configurations of major SRST features are provided in the following chapters of the Cisco Unified
SRST System Administrator Guide:
– “Setting up the Network”
– “Setting up Cisco Unified IP Phones”
– “Setting up Call Handling”
– “Configuring Additional Call Features”
– “Setting up Secure SRST”
– “Integrating Voice Mail with Cisco Unified SRST”
For SIP-specific SRST information, see Cisco Unified SIP SRST System Administrator Guide. To
configure SIP SRST features, see the Cisco Unified SIP SRST 4.1 chapter.

Cisco 2901 Specifications

General

Operating altitude	0 - 3000 m
Non-operating altitude	0 - 4570 m
Storage temperature (T-T)	-40 - 70 °C
Operating temperature (T-T)	0 - 40 °C
Storage relative humidity (H-H)	5 - 95 %
Operating relative humidity (H-H)	10 - 85 %
Ethernet LAN	Yes
Cabling technology	10/100/1000BASE-T(X)
Networking standards	IEEE 802.1Q, IEEE 802.1ag, IEEE 802.3, IEEE 802.3ab, IEEE 802.3af, IEEE 802.3ah
Ethernet LAN data rates	10, 100, 1000 Mbit/s
Ethernet interface type	Gigabit Ethernet
DHCP client	-
Routing protocols	BGP, EIGRP, OSPF
Supported protocols	IPv4, IPv6, IS-IS, IGMPv3, PIM SM, SSM, DVMRP, IPSec, GRE, BVD, MPLS, L2TPv3, PPP, MLPPP, MLFR, HDLC, RS-232, RS-449, X.21, V.35, EIA-530, PPPoE, ATM
USB version	2.0
RS-232 ports	1
Expansion slots	4 x EHWIC 2 x DSP 1 x ISM
Ethernet LAN (RJ-45) ports	2
Firewall security	Cisco IOS
Input current	1.5 A
AC input voltage	100 - 240 V
Power source type	AC
AC input frequency	47 - 63 Hz
Power consumption (typical)	40 W
Product color	Black
Rack capacity	1U
Safety	UL 60950-1, CAN/CSA C22.2 No. 60950-1, EN 60950-1, AS/NZS 60950-1, IEC 60950-1
Flash memory	256 MB
Internal memory	512 MB
Electromagnetic compatibility	47 CFR, ICES-003, EN55022, CISPR22, AS/NZS 3548, VCCI V-3, EN 300-386, EN 61000, EN 55024, CISPR 24EN50082-1

Weight and Dimensions

Depth	439.4 mm
Width	438.2 mm
Height	44.5 mm
Weight	6100 g