Interface Type FXS and DID trunk
Cisco IOS Software Release 12.4(20)T
Compliance FCC Class B device, CE
Safety Conformance UL1950
Address Signaling Formats

In-band DTMF

Out-of-band pulse (8-12 pps)

Signaling Modes

FXS: Loop start, ground start

DID: Immediate, Delay-dial, WinkStart

Disconnect Supervision Power denial (Calling Party Control, far-end disconnect)
MTBF 2,131,306 hours
Codecs Supported G.729 and G.711 uLaw
Echo Cancellation 24-128ms, multi-reflector, double-talk
Warranty 1 Year

Physical Specifications

Unit Dimensions (HxWxD) 1.75 in × 17.25 in × 17.30 in (4.45 cm × 43.82 cm × 44.00 cm)
Rack Height 1RU (rack unit)
Maximum Weight 16 lb (7.3 kg)
Airflow Front to side
Physical Connector RJ-11 (8)
Number of Connectors/Ports 8
Operating Temperature 40°–104°F (5°–40°C)
Operating Humidity 20%–80% non-condensing

Power Specifications

AC Power 100-240 volts AC, 50/60 Hz, 60 watts
AC Input Frequency 47 to 63 Hz
AC Input Current Range AC Power Supply (Maximum) 1.5 to 0.6A
AC Input Surge Current <50A
Maximum Power with AC Power Supply (Watts) 150
Power Interrupt Disconnect Call disconnect on power interrupt of > 600 ms

Regulatory Compliance


UL 60950-1 CAN/CSA C22.2 No. 60950-1 EN 60950-1 AS/NZS 60950-1 IEC 60950-1
EMC 47 CFR, Part 15 ICES-003 Class A EN55022 Class A CISPR22 Class A AS/NZS 3548 Class A VCCI V-3 CNS 13438 EN 300-386 EN 61000 (Immunity) EN 55024, CISPR 24 EN50082-1
Telecom TIA/EIA/IS-968 CS-03 ANSI T1.101 ITU-T G.823, G.824 IEEE 802.3 RTTE Directive
Environmental RoHS Compliant (Restriction of Hazardous Substances)

Supported Standards

Telco FCC Part 68, TS-016, TBR4, TS-038, CS03
Request For Comments (RFC)
SIP RFC2833 for DTMF signaling

A full list of specifications for the Cisco 2901 Integrated Services Router can be found on the Cisco Website.