Priority access for real-time traffic in contention-based networks
A contention-based network which allows real-time traffic to exist as multiple independent linked-list chains or under certain conditions to be assembled into multiple linked-list chains. A time separation is enforced between the various multiple chains, which are limited to a predetermined maximum number of stations that each can have in order to allow non-real-time stations to obtain timely access to the medium. Ones of the multiple chains may also be joined into a single chain. Blackburst contention is used to enable a chain to be reconstituted robustly from non-anticipated interruptions, such as the failure of one of its stations.
1. A contention-based communications network in which first and second independent linked-list chains of data packets, at least a given one of the first and second independent linked-list chains comprising data packets transmitted by a plurality of communications stations, once formed, are allowed to continue to exist independently for an indeterminate amount of time;
wherein said first and second independent linked-list chains of data packets are joined into a single linked-list chain only if the separation between said first and second independent linked-list chains becomes less than a particular amount.
2. The invention of claim 1 wherein said communications network includes a communications medium and wherein the communications stations transmitting the data packets of said first and second independent linked-list chains repetitively access said medium.
3. A method comprising the step of forming multiple linked-list chains of data packets, at least a given one of the multiple linked-list chains comprising data packets transmitted by a plurality of communications stations in a contention-based communications network, said method characterized in that said multiple linked-list chains, after having been formed, are not always thereafter joined into a single linked-list chain;
wherein first and second ones of said multiple linked-list chains of data packets are joined into a single linked-list chain only if the separation between said first and second ones of said multiple linked-list chains becomes less than a particular amount.
4. The invention of claim 3 wherein said multiple linked-list chains are independent linked-list chains which are allowed to continue to exist independently for an indeterminate amount of time.
5. The invention of claim 3 wherein said communications network includes a communications medium and wherein the communications stations transmitting the data packets repetitively access said medium.
6. A contention-based communications network in which first and second independent linked-list chains of data packets, at least a given one of the first and second independent linked-list chains comprising data packets transmitted by a plurality of communications stations, once formed, are allowed to continue to exist independently for an indeterminate amount of time;
wherein if the separation between said first and second independent linked-list chains becomes less than a particular amount, the separation between said first and second independent linked-list chains is caused to be increased.
7. The invention of claim 6 wherein said communications network includes a communications medium and wherein the communications stations transmitting the data packets of said first and second independent linked-list chains repetitively access said medium.
8. A method comprising the step of forming multiple linked-list chains of data packets, at least a given one of the multiple linked-list chains comprising data packets transmitted by a plurality of communications stations in a contention-based communications network, said method characterized in that said multiple linked-list chains, after having been formed, are not always thereafter joined into a single linked-list chain;
wherein if the separation between first and second ones of said multiple linked-list chains becomes less than a particular amount, the separation between said first and second ones of said multiple linked-list chains is caused to be increased.
9. The invention of claim 8 wherein said multiple linked-list chains are independent linked-list chains which are allowed to continue to exist independently for an indeterminate amount of time.
10. The invention of claim 8 wherein said communications network includes a communications medium and wherein the communications stations transmitting the data packets repetitively access said medium.