Hub-Site Pseudowire and Voice Trunking Gateway

RAD’s Gmux-2000 is a modular, high capacity hub-site pseudowire and voice trunking gateway, extending TDM-based services over next generation packet-switched networks. As a pseudowire access gateway, the Gmux-2000 is widely used in cellular backhaul, PSTN access and PBX backhaul applications. It supports industry standards for pseudowire emulation to transport multiple E1 or T1 links, channelized STM-1/OC-3 or channelized T3 over Gigabit Ethernet (GbE) uplinks.

As a carrier-grade voice trunking platform, the Gmux-2000 uses advanced compression algorithms to provide a 16:1 compression ratio, thus minimizing the bandwidth required for voice transmissions over packet networks and reducing cellular backhaul expenses.

• Reduces CapEx by enabling transition to cost-effective packet networks using TDM pseudowire access

• Allows carriers to continue delivering legacy services while migrating to NG IP transport

• Reduces operational costs by aggregation and compression

• Ensures carrier grade voice quality

• Enables carrier-class service continuity with fully redundant hardware

The Gmux-2000 is a cost-effective, modular pseudowire gateway that provides a high capacity, high-density solution for transporting multiple TDM links over IP, Ethernet and MPLS-based networks.

Incorporating ASIC-based pseudowire emulation capabilities, the Gmux-2000 supports TDMoIP, CESoPSN and SAToP per IETF, MFA Forum, and ITU-T standards. A choice of interfaces allows it to relay, concentrate and groom PDH and SDH/SONET traffic over PSN. Employing HDLCoPSN, the Gmux-2000 also delivers HDLC-based legacy traffic transparently.

The Gmux-2000 works opposite RAD’s IPmux TDM pseudowire gateways or Megaplex integrated access multiplexers for cost-effective, carrier-class TDM pseudowire access. Together, they provide carriers with a migration path to packet switched networks, while enabling them to continue delivering revenue-generating legacy services. The Gmux-2000 is also an ideal solution for alternative carriers wishing to add leased line services to their layer 2 portfolio, as well as to enterprises and organizations looking for ways to lower their IT expenses on PSTN connectivity and branch-to-branch communications. Other applications include cellular backhaul over packet transport.

Additionally, the Gmux-2000 can be deployed as a carrier grade platform for large voice compression applications, condensing numerous E1/T1 streams or an STM-1/OC-3 trunk over E1/T1, SDH/SONET or GbE links. Interoperable with RAD’s Vmux-2100, Vmux-210 and Vmux-110 voice trunking gateways, it employs TDMoIP multiplexing and advanced compression algorithms, as well as voice activity detection and silence suppression, to achieve up to 16:1 bandwidth savings. Such an effective compression ratio enables the unit to transmit up to 112 E1/T1 links over as few as seven E1/T1s, or over a single GBE link, while maintaining carrier-grade voice quality. By optimizing signaling channels as SS7, PRI and others, the Gmux-2000 further reduces the overall required bandwidth.

The Gmux-2000 is a 6U-high chassis, mountable in a 19-inch ETSI or ANSI rack. It features the following modules:

• Up to two GbE network uplink modules

• Two control modules

• Three AC or DC power supply modules

• Seven I/O modules (E1/T1 Ch. T3 and Ch. STM-1/OC-3 interfaces, or voice compression modules)

• A cooling fans module

Gigabit Ethernet network modules, each with a pair of redundant Gigabit Ethernet (GbE) ports, support Ethernet IEEE 802.3ad, 802.1Q (VLAN tagging) and VLAN stacking (Q-in-Q). Traffic classification is performed per 802.1p, IP ToS/DSCP or MPLS EXP bits.

E1/T1 pseudowire (PW) modules encapsulate E1/T1 traffic flows for transmission over packet network via the GbE network module. Several versions of the pseudowire module are available:

• E1/T1 modules with 28 external E1 or T1 interfaces for applications where individual E1/T1 ports are needed to interface with TDM devices.

• E1/T1 circuit emulation (PW) server modules are used together with the STM-1/OC-3 interface modules. Each E1/T1 PW server module is used to extract 21 E1 or 28 T1 internal channels coming from the channelized STM-1/OC-3 interface module and convert them to TDM pseudowire traffic flows.

T3 PW module includes a channelized T3 external interface, which carries 28 T1 data streams. Each internal T1 stream is emulated over PSN using TDMoIP, CESoPSN, SAToP, or HDLCoPSN pseudowire encapsulation. A fully equipped Gmux-2000 supports up to 7 channelized T3 modules (196 internal T1 data streams).

STM-1/OC-3 PW modules perform SDH/SONET multiplexing/demultiplexing of channelized STM-1/OC-3 trunks into separate, internal E1/T1 circuits (requiring E1/T1 PW server modules). Up to 63 E1 or 84 T1 internal channels are mapped into VC-12 or VT-1.5 streams to or from the channelized STM-1/OC-3 interface.

Each STM-1/OC-3 interface module provides a pair of ITU-T G.703 coax or G.957 fiber optic links, supporting 1+1 redundancy according to ITU-T G.783.

Voice compression modules – the Gmux-2000 supports up to seven voice compression modules, each capable of handling 12 or 16 incoming E1/T1s. The compressed voice is transmitted over the E1/T1 main link ports on the module itself, or through the internal bus to the GbE network module. These modules function as server modules, meaning they can receive the voice directly from the PBX/MSC (via a direct Telco cable), or they can process voice coming in from an STM-1 module. In addition, they can operate in point-to-multipoint topologies. This brings the maximum capacity of the Gmux-2000, when functioning as a central site voice trunking gateway, to 3,472 voice channels.

Control modules provide the SNMP and management interfaces, as well as database storage, enabling configuration and control of the entire Gmux-2000 system. Each control module provides redundant interfaces for connecting external G.812 station clocks and for alarm inputs/outputs. In addition, the Gmux-2000 supports Syslog (RFC3164) to enable remote reporting of alarms and traps to an external Syslog server.

Power supplies are hot-swappable plug-in modules. Up to three AC or DC power supply modules can be installed for load-sharing and redundancy. Two modules are required to drive a fully equipped Gmux-2000 system.

The Gmux-2000 features flexible management capabilities, including local management via an ASCII terminal (RS-232). In addition, remote management can be performed either inband or out-of-band, using one of the network ports or the dedicated management port, while maintaining separation between management and user traffic via the use of VLANs. Advanced FCAPS (Fault, Configuration, Accounting, Performance, Security), service provisioning and diagnostic tools are provided by RADview-SC/TDMoIP, RAD’s network management system, via an SNMP-based GUI.

The Gmux-2000 also supports a variety of configuration access channels, including CLI over Telnet, SNMP and TFTP. Incorporated security features include Secure Shell (SSH), secure FTP (SFTP), SNMPv3, and RADIUS, as well as management access control list (ACL).