FCD-T1LC T1 CSU/DSU from RAD
FCD-T1LC is a managed T1 CSU/DSU that can convert rates and interfaces for T1 and Fractional T1 services.
T1 CSU/DSU - FCD-T1LC supports a single or dual serial n × 56 kbps or n × 64 kbps data user interface. An Ethernet LAN interface can substitute the serial data interface port to allow LAN-to-LAN connectivity over TDM media.
FCD-T1LC can interconnect with RAD modular DXC (DACS) products and T1 equipment from other vendors, to support multilink star applications such as access to SDH networks. DXC, FCD, and Megaplex units operate together under centralized SNMP network
management.
The T1 interface
of the T1 CSU/DSU FCD-T1LC is compatible with virtually all carrier-provided T1 services, including ASDS from AT&T, and complies with TR-62411 and TR-62421. The T1 interface supports D4 and ESF framing formats. Zero suppression over the line is software-selectable for either transparent, B7ZS or B8ZS. The software-selectable integral CSU ensures a range of up to 2.1 km (1.3 miles).
The optional sub-T1 port can be configured with D4 or ESF framing, while the T1 main link framing is ESF. This enables connection of T1 D4 equipment over an ESF T1 network.
The unit can be programmed to assign data automatically from each data port into consecutive timeslots. The user can also assign timeslots manually.
Multiple clock source selection ensures maximum flexibility for supporting different applications. Timing for the T1 main link and sublink may come from the recovered receive clock, an internal oscillator, or one of the data ports.
Front panel LEDs indicate alarms, T1 signal loss, and diagnostic loopback operation. Rear panel LEDs on the Ethernet interface modules indicate LAN status and activity.
FCD-T1LC is a compact standalone unit. A rack mount adapter kit enables installation of one or two (side-byside) units in a 19-inch rack. (see Ordering section of data sheet).
T1 CSU/DSU - FCD-T1LC USER INTERFACES
FCD-T1LC features the following user interfaces:
Serial data interfaces: RS-530, V.35, X.21, V.36/RS-449
Ethernet 10/100BaseT LAN interface module with a built-in bridge (IR-ETH/QN).
FCD-T1LC has synchronous data ports that operate in the following clock modes:
DCE: The FCD units provide both transmit and receive clocks to the user equipment, with optional sampling of the incoming data with an inverted clock.
DTE1: The FCD units provide the transmit clock. The attached user equipment provides the receive clock.
DTE2: the attached user equipment provides both transmit and receive clocks.
The IR-ETH/QN interface module has a 10/100BaseT interface that supports VLAN frames, autonegotiation, fault propagation,
and automatic learning and aging.
The module transparently connects FCD-T1LC to remote LANs over T1 links. It filters Ethernet frames and forwards only frames that are destined for the WAN.
T1 CSU/DSU - FCD-T1LC MANAGEMENT & MAINTENANCE
Status and diagnostic information is defined, configured, and monitored using one of the following methods:
ASCII terminal connected to the async control port
SNMP management
Telnet.
FCD-T1LC has an internal SNMP agent that is managed by any generic SNMP station or by the RADview SNMP network management application.
The units support both dial-in and dial-out modem connections through the serial RS-232 port, by using SLIP or PPP protocol or a command line interpreter on an ASCII terminal. These out-of-band connections can be used for remote configuration and monitoring, as well as for sending callout alarm messages.
Up to 100 time-stamped alarms are available for retrieval through the supervision terminal, a Telnet host, or a RADview management station.
T1 CSU/DSU Inband management can be performed either by dedicated timeslot using standard Frame Relay protocol (RFC 1490), or by using the spare Sa bits on FDL bits for FCD-T1LC. This allows the user to setup, monitor, and run diagnostics on the remote unit. If
spare bits on FDL are used for inband access, they must be passed transparently end-to-end.
Maintenance capabilities include user-activated local and remote loopbacks on the E1/T1 main link, sublink, and data ports. The user can activate a BER test on the main link. Also, the main link responds to an ANSI FT1 RDL (T1E1.2/93-003) inband loop code, or a user-configured pattern generated by a remote FCD-T1LC, or DXC in a specific bundle of timeslots allocated only to that port. The user can also define BER or inband tests to run on any timeslot.
T1 network statistics are stored in memory, according to ANSI and AT&T standards. The statistical information may be retrieved by the service provider (ANSI only) or locally through the control port.
