Method and means for demand accessing and broadcast transmission among ports in a distributed star network
First Claim
1. A data communications system comprising:
- a transmission medium formed from an inverted three network of nodes and full duplex connecting links, the tree network having a network root node, said root node of a tree or subtree thereof having an in-degree of zero, each duplex link including an up-link and a down-link respectively defining a signal path direction toward or away from the network root node, each up and down-link being in either an idle or occupied state;
a plurality of transceiving ports attaching the network at selected nodes, ready ones of the ports transmitting messages at will;
each nodes includes;
means for ascertaining whether the state of each terminating up-link and down-link is idle or occupied; and
means responsive to the first occurring ascertained state transition from idle to occupied among the terminating up-links for completing an exclusive signal path connection to an outbound up-link only if the outbound up-link is concurrently idle.
0 Assignments
0 Petitions
Accused Products
Abstract
A demand access broadcast transmission method and means is capable of supporting random port access and any-to-any transmission at very high data rates. A communication medium (FIG. 2) formed from an inverted tree network of nodes (1, 18, 22) and full duplex connecting links (13, 17, 19) permits the establishment of a path lock up-link through the network from a demanding port to a root node on a first-come first-serve demand access basis with arbitration at each distinct tree node level (FIG. 3). Broadcast transmission is perfected down-link over all fan-out paths from the root node. Collision is avoided by locking a path to a port and by limiting race conditions among active ports to only the leading edges of messages. Thus, relinquishment of a broadcast channel overlapped with transmission of a message does not result in path seizure since the occurrence of message leading edges is the singular path connection invoking event.
-
Citations
12 Claims
-
1. A data communications system comprising:
-
a transmission medium formed from an inverted three network of nodes and full duplex connecting links, the tree network having a network root node, said root node of a tree or subtree thereof having an in-degree of zero, each duplex link including an up-link and a down-link respectively defining a signal path direction toward or away from the network root node, each up and down-link being in either an idle or occupied state; a plurality of transceiving ports attaching the network at selected nodes, ready ones of the ports transmitting messages at will; each nodes includes; means for ascertaining whether the state of each terminating up-link and down-link is idle or occupied; and means responsive to the first occurring ascertained state transition from idle to occupied among the terminating up-links for completing an exclusive signal path connection to an outbound up-link only if the outbound up-link is concurrently idle. - View Dependent Claims (2, 3, 4, 5)
-
-
6. A method for any-to-any port transmission of messages through an inverted tree network of nodes and full duplex connecting links, the tree network having a network root node, said root node of the tree or sub-tree thereof having an in-degree of zero, each duplex link including an up-link and a down-link respectively defining a signal path direction toward or away from the network root node, the method being executable by ready-to-transmit ones of a plurality of transceiving ports individually coupling the network at selected nodes, comprising the steps of:
-
establishing a message initiated path lock up-link through the network from a ready-to-transmit one of the ports to the network root node only by way of a first come, first serve demand access discipline among the up-links terminating at each distinct tree node level to a concurrently idle out-bound up-link; and broadcast transmitting any message over all down-links fanning out from the network root node, which message was received over an up-link path connection to said network root node. - View Dependent Claims (7, 8, 9, 10, 11, 12)
-
Specification