# US 5,838,687 A · Slot reuse method and arrangement > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,838,687 A - Document ID: US5838687A - Status: Granted - Kind: A - Application number: 08/757,347 - Filed: 1996-11-27 - Granted: 1998-11-17 - Earliest claimed: 1996-11-27 - Assignees: Dynarc Inc. - Inventors: Lars Ramfelt - Web page: https://patentgrep.com/patent/US5838687A ## CPC - H04Q 11/0478: {Provisions for broadband connections} - H04L 12/2852: {Metropolitan area networks} - H04L 12/422: {Synchronisation for ring networks (Time Division Multiplex ring networks, e.g. SDH/SONET H04J3/085)} - H04L 12/6418: {Hybrid transport} - H04J 3/07: using pulse stuffing for systems with different or fluctuating information rates {or bit rates} - H04J 2203/0044: Bus, e.g. DQDB - H04J 2203/0046: User Network Interface - H04L 2012/6435: {Bus} - H04L 2012/6451: {Deterministic, e.g. Token, DQDB} - H04L 2012/6456: {Channel and bandwidth allocation} - H04L 2012/6459: {Multiplexing, e.g. TDMA, CDMA} - H04Q: SELECTING (switches, relays, selectors H01H; wireless communication networks H04W) - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) - H04J: MULTIPLEX COMMUNICATION (transmission in general H04B; peculiar to transmission of digital information H04L5/00; systems for the simultaneous or sequential transmission of more than one television signal H04N7/08; in exchanges H04Q11/00; stereophonic systems H04S) ## Abstract The present invention relates to a slot reuse method and arrangement for increasement of the throughput in a DTM (Dynamic Synchronous Transfer Mode) network. The slot reuse according to the invention comprises extending the DTM block token format to include parameters describing the segment(s) between source and destination node, reserving block token capacity only on the segment(s) between source and destination node, and enabling simultaneous transmissions in the same slot over disjointed segments of the network. The slot reuse can also comprise merging two or more segment-consecutive tokens, representing the same slot range, into a single token when existing in the free pool of a node. ## Claims ### Claim 1 A slot reuse method for increasing a throughput in a dynamic synchronous transfer mode (DTM) network, the method comprising the steps of: providing a DTM block token format having a capacity; providing a source and a destination node; providing parameters and segments; providing disjointed segments of the DTM network; providing a plurality of slots; extending the DTM block token format to include the parameters describing the segments disposed between the source and the destination node; reserving the capacity of the DTM block token format only on the segments disposed between the source and the destination node; and transmitting the throughput simultaneously in the same slot over disjointed segments of the DTM network. ### Claim 2 (depends on 1) The slot reuse method according to claim 1 wherein the method further comprises the steps of providing a slot range and a free pool of a node and providing two or more segment-consecutive tokens represented in the same slot range and merging the segment-consecutive tokens into a single token when existing in the free pool of the node. ### Claim 3 (depends on 1) The slot reuse method according to claim 1 wherein the method further comprises the step of providing a central token management scheme and implementing the slot reuse method into the central token management scheme. ### Claim 4 (depends on 1) The slot reuse method according to claim 1 wherein the method further comprises the steps of providing a distributed token management scheme and implementing the slot reuse method into the distributed token management scheme. ### Claim 5 (depends on 1) The slot reuse method according to claim 1 wherein the slot reuse method further comprises the steps of combining a centralized model and a distributed model into a resource management system by using a small set of token server nodes and implementing the slot reuse method into the resource management system. ### Claim 6 (depends on 2) The slot reuse method according to claim 2 wherein the slot reuse method further comprises the steps of combining the slot reuse method with a defragmentation method wherein the defragmentation method comprises the steps of: providing a plurality of home nodes; defining the home node for each token during a network start-up; sending back free tokens to their respective home nodes when a significant time has passed; and merging two or more slot-consecutive tokens with the slot range into a single token when existing in the free pool of the node. ### Claim 7 (depends on 6) The slot reuse method according to claim 6 wherein step of defining the home node includes the step of defining the home node for each token during network operation. ### Claim 8 (depends on 6) The slot reuse method according to claim 6 wherein step of defining the home node includes the step of defining the home node for each token during network operation so that the tokens sharing the same home node defines at least partially a continuous slot range. ### Claim 9 (depends on 6) The slot reuse method according to claim 6 wherein two or more tokens having the same slot range are merged into a single token when existing in the free pool of the node. ### Claim 10 (depends on 9) The slot reuse method according to claim 9 wherein the step of merging includes providing a number of slot and segment-consecutive tokens having a slot range and a segment range and merging the slot and segment-consecutive tokens having the same slot or segment range and prioritizing a segment merge before a slot number merge although the number of tokens is increased. ### Claim 11 (depends on 1) The slot reuse method according to claim 1 wherein the method further comprises the steps of providing a slot number and segment number dimension and selecting a token from a token pool by using a best-fit selection system in the slot number and segment number dimension when the token is requested at a node and choosing the token that has the requested capacity with a smallest area in a token map. ### Claim 12 (depends on 1) A slot reuse method according to claim 1 wherein the method further comprises the step of requesting a token having a requested capacity from other nodes and if no token fulfills the requested capacity minimizing the number of tokens required. ### Claim 13 A slot reuse arrangement for increasing a throughput in a dynamic synchronous transfer mode (DTM) network comprising: a plurality of slots having disjointed segments; an extended DTM block token format including parameters describing segments disposed between a source and a destination node; and nodes arranged to reserve block token capacity only on segments disposed between the source and the destination node to permit a simultaneous transmission in the same slot over the disjointed segments of the DTM network.