Samsung Ubigate iBG3026, Configuration Manual

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Ubigate iBG3026 Configuration Guide/Ed.00
© SAMSUNG Electronics Co., Ltd.
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V.35
V.35 is a combination of single-ended and differential synchronous interface.
It uses V.35 electrical characteristics for clock and data(differential) and
V.28(EIA-232) electrical characteristics for control signals(single-ended).
It is typically limited to a maximum throughput of 10Mbps. For the interface,
separate clock lines are used for receiving and transmitting data and MRAC-
34 connector is used.
HSSI Interface
The High-Speed Serial Interface(HSSI) is a DTE/DCE interface and is
developed to address the need for high-speed communication over WAN links.
HSSI defines both electrical and physical interfaces on DTE and DCE devices.
It operates at the physical layer of the OSI reference model.
The maximum signaling rate of HSSI is 52 Mbps. At this rate, HSSI can
handle the T3 speeds(45 Mbps) of many of today's fast WAN technologies, as
well as the Optical Channel-1(OC-1) speeds(52 Mbps) of the synchronous
digital hierarchy(SDH). In addition, HSSI easily can provide high-speed
connectivity between LANs, such as Token Ring and Ethernet.
The use of differential emitter-coupled logic(ECL) helps HSSI achieve high
data rates and low noise levels. ECL has been used in Cray computer system
interfaces for years and is specified by the ANSI High-Performance Parallel
Interface(HIPPI) communications standard for supercomputer LAN
communications. ECL is an off-the-shelf technology that permits excellent
retiming on the receiver, resulting in reliable timing margins.
HSSI uses a subminiature, FCC-approved 50-pin connector that is smaller
than its V.35 counterpart. To reduce the need for male-male and female-female
adapters, HSSI cable connectors are specified as male. The HSSI cable uses
the same number of pins and wires as the Small Computer Systems Interface
2(SCSI-2) cable, but the HSSI electrical specification is more concise.
The flexibility of the HSSI clock and data-signaling protocol makes user(or
vendor) bandwidth allocation possible. The DCE controls the clock by
changing its speed or by deleting clock pulses. In this way, the DCE can
allocate bandwidth between applications. For example, a PBX may require a
particular amount of bandwidth, a router another amount, and a channel
extender a third amount. Bandwidth allocation is key to making T3 and other
broadband services affordable and popular.