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EP0509648A1 Expired / Lapsed EP ⏱️ 0.0 years remaining

Multicast server apparatus

Assignee: Roke Manor Research Ltd
•
Filing: 1992-03-20
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Granted: —
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Expires: 2012-03-20
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Abstract

Abstract Multicast server apparatus operative to effect the onward transmission of data cells to a plurality of different addresses, comprises a switch function unit having an input port, an output port and a transfer port, data cells for multicasting being routed from the input port to the transfer port, first and second header translation units each having an input terminal and an output terminal, which translation units serve respectively as a chainer and as a distributor, the input terminals of the chainer and the distributor respectively being coupled to the transfer port of the switch function unit to receive data for multicasting, the chainer being effective to change address data associated with each data cell fed thereto to a form recognisable by the distributor and to feed back such data cell together with its changed address data to the said transfer port, and the distributor being effective to convert recognisable address data associated with data cells fed thereto to corresponding route address tags and to feed cells having such address tags to the output port of the switch function unit, whereby a data cell for multicasting is distributed by the multicasting server apparatus separately to the said plurality of different addresses as identified by the said tags.

Inventors

  • 👤 Simon Paul Davis
  • 👤 Ian Bernard Stewart

Bibliographic Details

Application Number —
Jurisdiction EP
Data Source google_patents
Last Synchronized 2026-11-03 05:13
CPC Classifications
H; H04; H04L; H04L49/00; H04L49/30; H04L49/3009; H04L12/00; H04L12/02; H04L12/16; H04L12/18; H04L49/20; H04L49/201; H04L49/203; H04L49/3081; H04L49/309

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 206 words
Multicast server apparatus operative to effect the onward transmission of data cells to a plurality of different addresses, comprising a switch function unit having an input port, an output port and a transfer port, data cells for multicasting being routed from the input port to the transfer port, first and second header translation units each having an input terminal and an output terminal, which translation units serve respectively as a chainer and as a distributor, the input terminals of the chainer and the distributor respectively being coupled to the transfer port of the switch function unit to receive data for multicasting, the chainer being effective to change address data associated with each data cell fed thereto to a form recognisable by the distributor and to feed back such data cell together with its changed address data to the said transfer port, and the distributor being effective to convert recognisable address data associated with data cells fed thereto to corresponding route address tags and to feed cells having such address tags to the output port of the switch function unit, whereby a data cell for multicasting is distributed by the multicasting server apparatus separately to the said plurality of different addresses as identified by the said tags.
Claim 2
Dependent Claim 111 words
Multicast server apparatus as claimed in claim 1 wherein the header translation units each comprise, synchronisation means operative to detect the start and finish of each cell received, a frame check sum (FCS) means, for performing a error check on data received by the unit, a buffer store into which received data is loaded having been error checked by the FCS, header translation table means operative to modify address data, or routing tag data, associated with a cell stored in the buffer store and FCS generator means operative to generate frame check data for each cell and to route the cell together with the frame check data to an output terminal.
Claim 3
Dependent Claim 53 words
Multicast server apparatus as claimed in claim 2 wherein each header translation unit comprises a RAM such that data in the RAM of a unit which serves as a chainer facilitates address data modification and such that data in the RAM of a unit which serves as a distributor facilitates routing tag conversion.
Claim 4
Dependent Claim 47 words
A multicast server apparatus as claimed in claim 3 wherein each header translation unit includes a series/parallel converter via which the buffer store is fed from the FCS means and a parallel/series converter means via which the buffer store is arranged to feed the FCS generator means.
Claim 5
Dependent Claim 20 words
A multicast server apparatus as claimed in claim 1 and substantially as hereinbefore described with reference to the accompanying drawings.

References Cited (Backward Citations)

WO1989009521A1 Cited

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