Compaq ProLiant 1600 White Paper page 18

ECG068/0798
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HITE APER
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The Ethernet switching hub only routes video packets that are addressed to the specific client
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devices on the appropriate output ports. This keeps video traffic flowing smoothly to the desktops
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that need it, and insulates the corporate backbone network from high bandwidth video.
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This establishment of dedicated "subnets" prevents conflicts between video and other data, and
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also prevents video from hogging shared network bandwidth. Switched Ethernet is often
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recommended for high-quality video to the desktop as it can often use most of the existing
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network infrastructure such as Network Interface Cards (NICs), hubs, and cabling.
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Fast Ethernet:
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Fast Ethernet generally refers to high speed Ethernet such as 100BaseT which supports 100Mbps
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bandwidth—a tenfold increase over 10Mbps 10BaseT. Fast Ethernet works the same from a
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. . protocol and access point of view as standard Ethernet, only faster. The higher bandwidth
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provides better support for streaming video. Many enterprises install Fast Ethernet as an upgrade
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or as a network backbone. The next generation of Fast Ethernet—Gigabit Ethernet—is in
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development.
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ATM:
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Asynchronous Transfer Mode uses hardware switching to provide not only high speed—25Mbps
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to 2.5Gbps—but it also a guaranteed Quality of Service (QoS) and multicasting through a circuit-
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switched connection. It uses fixed 53 byte packets and was designed from the outset for
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multimedia data transmission such as video, sound, and images. Physical media includes twisted
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pair, coax, and fiber. Because of its speed and expense, it was originally used for wide-area long-
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haul networks, but is now beginning to be deployed as a local area backbone.
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Public Internet
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The public Internet is moving at a breathtaking pace in terms of content, access, and subscribers.
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There is a strong motivation to be able to deliver video content for a number of potential
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applications including webcasting, product advertising and catalogs, interactive shopping, and
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. . virtual travel.
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Access
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Access to the public Internet is generally done through an "access network" that connects to the
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"core network" or backbone of the Internet.
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HTTP
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Web
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Server
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. . Video
HTTP
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Server
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(Tunnel)
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18
Core
Network
New
Protocols:
RTP
UDP
RTSP
TCP
RSVP
IPv6
Internet Access to Video
Access
Network
Access Methods:
Modem, ISDN, ADSL,
Cable modem
Client