The DXC digital cross-connect family consists of modular multiservice access nodes providing non-blocking DS0 cross-connect for up to 120 lines. Plug-in interface modules can accommodate up to eight links each. Many services are supported, including n x 56/64 kbps, ISDN, E1, T1, E3, T3, STM-1 and inverse multiplexing.
Cross-connect, groom and broadcast
All DXC modules allow maximum flexibility between ports. A user-programmable connection matrix connects any incoming 56/64 kbps timeslot to any outgoing 56/64 kbps timeslot. It supports cross-connect functions such as drop-and-insert, distribute and collect.
The DXC digital cross-connect family enables grooming fractional traffic from the user side into full E1/T1, E3/T3 or STM-1 trunks, for connection to the network. Grooming and bandwidth maximization are implemented by placing the n x 56/64 kbps data channels into an E1 or T1 frame (including internal E1/T1 of the E3 or T3 modules or VC-12 containers of the STM-1 module), using only the required number of timeslots. This provides fractional CSU/DSU functionality.
The DXC digital cross connect family can broadcast any traffic combination from a single input to numerous destinations. Channel relocating and half duplex conferencing are also supported.
E1/T1 converter
The DXC family is also capable of converting between E1/T1 ports. A-law/µ-law and signaling conversion are performed according to E1 and T1 standards. DXC-8R converts up to 16 ports. T1 traffic can be directly extracted from the STM-1 module (which can act as a converter for up to 30 T1 links).
E3, T3 and STM-1 multiplexer modules
These modules provide full channelization functionality for the multiplexing and demultiplexing of DS0 traffic. Aggregated payload is 34 Mbps for E3; 45 Mbps for T3; and the equivalent of 61 Mbps for STM-1 (one chassis). When chaining a number of units, the aggregated payload is equivalent to 155 Mbps.
Cross-connect system redundancy
The DXC digital cross-connect family provides flexible redundancy and protection to accommodate each user’s needs and help minimize service downtime. The modules’ link protection is user-programmable. Hardware protection and partial or full redundancy can be added at any time.
DXC-8R has built-in full system redundancy. The compact 1U-high unit can support up to 32 ports. It is fully redundant and includes two power supplies, two common logic modules and four I/O slots for the plug-in interface modules.
Various timing options cover all timing possibilities for the E1/T1 interface. These include internal clock, external clock and loopback timing sourcing from any selected E1/T1, n x 56/64 kbps, E3/T3 or STM-1 port.
Setup, management and diagnostic tools
Setup, control and diagnostics can be performed via an ASCII terminal or Ethernet port. A built-in SNMP agent enables three management options:
Configuration and diagnostics of remote services are provided through either TS0 or a dedicated timeslot, which can be groomed by the DXC alongside the payload traffic (for up to 30 management links supporting PPP). Out-of-band management is available via PPP or SLIP. Diagnostic loopback support for most modules includes loopback toward the local or remote DTE. Data monitoring capabilities are supported by configuring any high-speed port to monitor any given port in the enclosure.
The DXC can be controlled remotely via dial-up modem.
Modules
Most modules are supported by all DXC chassis. A variety of port densities are available, from single-port to 8-port modules. Most modules support hardware and/or line redundancy and ensure a protective switching time of <50 msec.
Additional features include integrated modems (fiber, IDSL, and SHDSL), range extenders and powerful, integrated testing capabilities that minimize network downtime. The DXC features built-in BER testing, programmable on any port on a timeslot level, and loopback capabilities.
STM-1 terminal module
DFSTM-1 one-port or two -port standard 155 Mbps STM-1 interface provides direct access to the STM-n SDH ADM at the STM-n level. The STM-1 terminal multiplexer (TM) module grooms up to 61.44 Mbps of traffic to a standard STM-1 frame over fiber or copper. The two-port module can be used in a drop-and-insert daisy-chain to expand services or for redundancy. When daisy-chaining units, full payload is supported.
E3/T3 modules
DE3 one-port E3 interface module provides access to a standard E3 frame over an unbalanced coax or fiber links. A user-programmable connection table enables fractional data traffic from various sources to be groomed into full internal E1 trunks.
DT3 one-port T3 interface module provides access to a standard T3 frame over an unbalanced T3 or fiber link. A user-programmable connection table enables fractional data traffic from various sources to be groomed into full internal T1 trunks.
T3/747 (see special modules).
E1 modules
D4E1/D8E1 four-port or eight-port interface modules transmit to a range of up to 2.2 km (1.4 miles) by using the built-in LTU. They have a data rate of up to 2.048 Mbps per port, and support BERT and loopback per time slot. Resistive attenuation adjustment (10 dB – 30 dB) supports signaling monitoring applications (such as SS7 network maintenance and billing).
DE1B two -port E1 interface module transmits to a range of up to 2.2 km (1.4 miles) with an LTU option. BERT and loopback per timeslot are optional. Automatic traffic bypassing is optional.
T1 modules
D4T1/D8T1 four-port or eight-port interface modules transmit to a range of up to 2.2 km (1.4 miles) by using the built-in CSU. The data rate is up to 1.544 Mbps per port. The module supports BERT and loopback per timeslot. Attenuation adjustment (10 dB – 30 dB) supports signaling monitoring applications (such as SS7 network maintenance and billing).
DT1B two-port T1 interface module transmits to a range of up to 2.2 km (1.4 miles) with a CSU option. BERT, loopback per timeslot and automatic traffic bypassing are optional.
xDSL modules
D8SL eight-port interface module uses standard SHDSL technology to extend the range of E1 connections over 2-wire cable up to 10.7 km (6.6 miles).
D4SL four-port interface module uses standard SHDSL technology to extend the range of E1 connections over 2-wire cable up to 10.7 km (6.6 miles).
D8U 8-port module enables IDSL extension to remote modems at ranges of up to 5.5 km (3.4 miles) or as ISDN (U interface) 2B+D channel transmission at ranges of up to 5.5 km (3.4 miles). Data rate is up to 128 kbps per port.
Special modules
D8HS eight-port n x 56/64 kbps data module provides eight high-speed synchronous data channels, independently selected for V.35, RS-422/V.11, X.21 or RS-530 interface.
DHS two-port n x 56/64 kbps data module provides two high-speed synchronous data channels. Each channel is independently selected for 10/100BaseT Ethernet bridge including VLAN support, 10BaseT Ethernet router, V.35, RS-422/V.11, X.21 or RS-530 interface.
DIM is a digital inverse multiplexer module for up to eight E1/T1 channels (15.7 Mbps of traffic). The module has an integrated 10/100BaseT Ethernet bridge, including VLAN support, 10BaseT Ethernet router, V.35, RS-530, HSSI, X.21 or E1 interface. Traffic can be groomed directly to any of the E1, E3, T1, T3, T3/747 or STM-1 modules. The module is interoperable with any of the IMX products.
DT3/747 1-port T3 interface module provides access to standard T3 according to G.747 from 21 independent E1 or T1 channels, over a copper or fiber interface.
Applications
The DXC family serves as the central solution for many RAD or other standards-based products. The DXC-8R chassis is geared for installations that require a compact unit (e.g., cellular base stations) or lower capacity of up to 40 ports (e.g., a carrier’s initial stage of deployment).
Typical applications:
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E1/T1 access platform over SHDSL, IDSL, fiber or copper, featuring data/voice concentration and integrated management
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Conversion/gateway between T1 and E1 networks, for both data and voice
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High-speed access (e.g., Ethernet, HSSI) to a carrier’s high speed digital backbone over n x E1/T1, E3/T3 or STM-1, where n represents one to eight lines
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Distributing services from an SDH or other network to a wide variety of end users by creating an E1/T1 or STM-1 daisy chain
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Grooming fractional trunks to full trunks
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Maximizing data traffic payload over E3, T3 or STM-1 trunks
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Grooming of monitoring signals (SS7 or other) for advanced services and Quality of Service
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Broadcasting identical data to multiple destinations
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Cross-connecting trunks at the point-of-presence (POP)
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Grooming a variety of services at the POP over n x E1/T1, E3/T3 or STM-1
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Video conferencing using DIM, inverse multiplexing modules
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