3Com SuperStack II PathBuilder S330 Reference Manual page 18

4 C 1: S D
HAPTER YSTEM ESCRIPTION
Support of Frame Relay (service and network) interworking, ATM DXI, and
SDLC/HDLC pass-through, through the high-performance serial frame data
interface.
Choice of either single-mode or multi-mode OC3/STM-1 (separate units),
through the OC3/STM-1 module. Single-mode enables higher-speed trunking if
you have access to fiber WAN, while multi-mode is ideal for connecting
high-speed servers, switches, or hubs equipped with multi-mode fiber
connections.
Three expansion slots, allowing you to add other advanced features, such as
T1-DSX or E1 CBR for voice and video, voice compression, Ethernet 10/100,
DS3/E3, or 4 additional T1/E1 IMA ports.
4x switch switching architecture, including four priority queues (three queues
shaped and one bulk shaper) with user-defined queue sizes and early and
partial packet discard capability.
Device management via VT100 menu-driven interface, Telnet, or SNMP, with
local, remote, and in-band access.
The following optional modules are available for use with the PathBuilder S330
switch:
The four-port CBR module services traffic generated by your existing PBXs,
channels, T1/E1 multiplexers, CSU/DSUs, and video conferencing devices. The
CBR module consists of one V.35/RS-449 and three T1-DSX or E1 interfaces,
which support both structured and unstructured services, in accordance with
the ATM Forum's Circuit Emulation Service (CES) specifications. The CBR
module provides a smooth migration from legacy CBR service (PBX/voice/video)
to ATM service. It also supports all relevant ATM and T1/E1 standards, ensuring
easy integration of existing equipment into new ATM networks.
The one-port voice compression module (VCM) is similar in function to the CBR
module, but it employs compression algorithms that allow more voice calls to
be placed through the same bandwidth. The VCM's T1-DSX/E1 interface
connects to a PBX trunk, which may use CAS or CCS signaling. Its 24/30 DS0
channels can carry individual voice, fax, modem, or data connections. You can
also bundle multiple DS0s to provide connections for high-rate applications
such as video conference or multiple-link PPP. For CCS, a DS0 is used as an
ISDN D-channel for carrying signal messages.
The Ethernet 10/100 module provides a one-port PCI Ethernet interface that
you can set for 10 or 100Mbps, full or half duplex, or configure for
autosensing.
The DS3/E3 module provides a DS3 or E3 interface, typically used for
terminating/accessing the public or private ATM WAN services. However,
depending on your local applications, you can also use these modules for
taking local DS3 or E3 ATM traffic across the WAN.
The four-port IMA expansion card adds four ports to the T1/E1 UNI with IMA
interface, thereby providing the PathBuilder S330 with 8-port IMA
functionality.
Figure 1 shows the PathBuilder S330 switch with the optional CBR module
installed in expansion slot 7, VCM in slot 8, and DS3/E3 UNI module in slot 9.