This newfound interest in multimedia applications will require net managers to give careful consideration to the technology's impact on existing local-and wide-area networks. In addition, users devising new LANs will have to factor in the wild card variables associated with running various multimedia wholesale silver ring on a network.
The primary obstacle to supporting network multimedia applications is the performance limitations of today's LANs and WANs. Typical LAN speeds of 10M and 16M bit/sec "are inadequate for true multimedia distribution," says Raymond Neff, vice-president of information services at Cleveland-based Case Western Reserve University (CWRU). He oversees CWRUnet, the university's end-to-end fiber network.
CWRUnet supports multimedia --to a degree. Data is run over 10M bit/sec Ethernet and 16M bit/sec token-ring networks, while audio and video run on parallel but separate LANs. A true multimedia network would have an ample supply of bandwidth to support wholesale silver pendant types of traffic on the same LAN.
But supporting data, voice and video on one network is no small feat. The network requirements for data are different from those for voice and video. Data tends to have moderate bandwidth needs and is bursty by nature, making it well suited for connectionless, packetized environments, where multiple transmissions are intermixed.In addition, data requires rigid error control, which is implemented via retransmission of errored data packets. Retransmission introduces unpredictable delays in a signal's arrival wholesale silver bracelets its destination. However, this does not materially alter the information the data represents.
Voice and video, by contrast, manifest themselves as steady high-bandwidth (16K to 384K bit/sec) transmissions for the duration of a session. That means a voice or video link could chew up an hour of connect time, while a 1M-byte data file can be transmitted in a wholesale silver earring second.Current 10M and 16M bit/sec LANs are not engineered to support such steady high-bandwidth traffic. Therefore, running voice and video over them poses the threat of traffic congestion, which in turn, would delay response times for LAN-based data applications.
"Most managers won't allow (multimedia applications) on their networks because it would melt them down," says Charles Giancarlo, vice-president of business matters for the ATM Forum and vice-president of marketing at Adaptive Corp., which manufactures T-3 Synchronous Optical Network (SONET) and Asynchronous Transfer Mode (ATM) wideband switches for telecommunications networks.
Voice and video transmissions also differ from data transmissions in the amount of wholesale silver necklace control required. Unlike data, voice and video transmissions do not require strict error control because minor error rates and the dropping of an occasional frame are virtually unnoticeable.ut delays caused by data retransmissions can cause portions of the audio and video to be lost or "clipped," thereby distorting the message.Although Ethernet, token-ring and Fiber Distributed Data Interface LANs are designed for data, it is possible to run real-time voice and video over them using products such as Fluent, Inc.'s FluentLinks, which is currently in prerelease testing.
FluentLinks is a series of hardware boards for Novell, Inc. NetWare servers and workstations that come with a NetWare Loadable Module for storing digital video files on a NetWare server and transmitting them on request over the LAN to workstations.
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