Method for access control in a multiple access system for communications networks

• US 6,567,416 B1
• Filed: 05/22/1998
• Issued: 05/20/2003
• Est. Priority Date: 10/14/1997
• Status: Expired due to Term

• Current Assignee: WSOU Investments, LLC (WSOU Holdings, LLC)
• Original Assignee: Lucent Technologies, Inc. (Nokia Corporation)
• Inventors: Chuah, Mooi Choo
• Primary Examiner(s): TON, DANG T
• Application Number:
  US09/084,072
• Time in Patent Office: 1,824 Days
• Field of Search: 370/389, 370/418, 370/503, 370/441, 370/442, 370/347, 370/428, 370/411, 370/412, 370/413, 370/414, 370/416, 370/419, 370/445, 370/444, 370/447, 370/461, 370/462, 370/449, 370/450, 370/455, 370/458, 370/459, 370/480, 370/341, 370/343, 370/342, 370/229, 370/230-232, 370/350, 370/395.1, 370/522, 370/524, 340/825.01, 340/825.5, 340/825.03, 340/825.51, 455/445, 455/450, 455/451, 455/452, 455/453, 455/455, 455/464
• US Class Current: 370/418
• CPC Class Codes: H04L 43/00 Arrangements for monitoring or testing data switching networks
• CPC Class Codes: H04L 43/0829 Packet loss
• CPC Class Codes: H04L 43/16 Threshold monitoring
• CPC Class Codes: H04L 47/10 Flow control; Congestion control
• CPC Class Codes: H04L 47/15 in relation to multipoint traffic arrangements for broadcast or multicast in data networks H04L12/18
• CPC Class Codes: H04L 47/26 using explicit feedback to the source, e.g. choke packets
• CPC Class Codes: H04L 47/286 Time to live
• CPC Class Codes: H04L 47/30 in combination with information about buffer occupancy at either end or at transit nodes
• CPC Class Codes: H04L 47/32 by discarding or delaying data units, e.g. packets or frames
• CPC Class Codes: H04L 47/70 Admission control; Resource allocation
• CPC Class Codes: H04L 47/72 using reservation actions during connection setup
• CPC Class Codes: H04L 47/788 Autonomous allocation of resources
• CPC Class Codes: H04L 47/805 QOS or priority aware
• CPC Class Codes: H04L 47/824 Applicable to portable or mobile terminals
• CPC Class Codes: H04W 28/02 Traffic management, e.g. flow control or congestion control
• CPC Class Codes: H04W 28/14 using intermediate storage
• CPC Class Codes: H04W 28/26 Resource reservation
• CPC Class Codes: H04W 52/10 Open loop power control
• CPC Class Codes: H04W 52/50 at the moment of starting communication in a multiple access environment
• CPC Class Codes: H04W 74/0875 with assigned priorities based access
• CPC Class Codes: H04W 8/04 : Registration at HLR or HSS [Home Subscriber Server]
• CPC Class Codes: H04W 88/08 : Access point devices
• CPC Class Codes: H04W 92/10 : between terminal device and access point, i.e. wireless air interface

Abstract

A method for access control in a wireless network having a base station and a plurality of remote hosts includes the optional abilities of making dynamic adjustments of the uplink/downlink transmission ratio, making dynamic adjustments of the total number of reservation minislots, and assigning access priorities by message content type within a single user message stream. The method of the invention further provides for remote wireless host paging and for delayed release of active channels by certain high priority users in order to provide low latency of real-time packets by avoiding the need for repeated channel setup signaling messages. In the preferred embodiment, there are N minislots available for contention in the next uplink frame organized into a plurality of access priority classes. The base station allows m access priority classes. Each remote host of access priority class i randomly picks one contention minislot and transmits an access request, the contention minislot picked being in a range from 1 to N_i where N_(i+1)<N_i and N₁=N. In an alternate embodiment of a method for access control according to the present invention, each remote host of access priority class i and with a stack level that equals 0, then transmits an access request with a probability P_i where P_(i+1)<P_i and P₁=1.

Claims

1. A method for access control in a wireless communications network, said network having a base station and a plurality of remote hosts between which uplink and downlink frames flow, said base station having a downlink queue, each of said remote hosts having an uplink queue, each of said uplink frames containing contention minislots, said contention minislots being organized into a plurality of access priority classes, each of said access priority classes being characterized by a different priority, the method comprising:

configuring a number N of said contention minislots in each of said uplink frames;

allowing for a number m of said plurality of access priority classes at said base station;

at each of said remote hosts of an access priority class i, randomly picking one of said contention minislots in which to send an access request, said picked contention minislot being in a range from 1 to N_i where N_(i+1)<

N_i and N_i=N when i=1;

receiving at least one of said access requests at said base station;

identifying uncollided ones of said received access requests; and

granting access to one of said remote hosts that made an uncollided one of said access requests.

2. The method of claim 1, wherein the value of N is dynamically adjustable based on the percentage of idle ones of said contention minislots and the combined lengths of all of said uplink queues.

3. The method of claim 2, wherein each of said uplink frames also contains a number of dataslots, the value of N being dynamically adjusted by the steps of:

if the total length of all said uplink queues is greater than a high threshold, and the percentage of said idle ones of said contention minislots is greater than a first idle threshold, and a state value is not “

1”

, decreasing N by a number k, increasing the number of dataslots by 1, and setting said state value to “

1”

; and

if the total length of all said uplink queues is not greater than said high threshold, and said total uplink queue length is less than a low threshold, and the percentage of said idle ones of said contention minislots is less than a second idle threshold and said state value is “

1”

, increasing N by the number k, decreasing the number of dataslots by 1, and setting said state value to “

0”

.

4. The method of claim 2, wherein each of said uplink frames also contains a number of dataslots, the value of N being dynamically adjusted by the steps of:

if the total length of all said uplink queues is greater than a first high threshold and the percentage of said idle ones of said contention minislots is greater than a first idle threshold and a state value if “

0”

, decreasing N by a number 2k, increasing the number of dataslots by 2, and setting said state value to “

2”

;

if the total length of all said contention minislots is greater than said first idle threshold and said state value is “

I”

, decreasing N by a number k, increasing the number of dataslots by 1, and setting said state value to “

2”

;

if said total uplink queue length is not greater than said first high threshold, and if said total uplink queue length is greater than a second high threshold and the percentage of said idle ones of said contention minislots is greater than said first idle threshold, and said state value is “

0”

, decreasing N by the number k, increasing the number of dataslots by 1, and setting said state value to “

1”

;

if said total uplink queue length is not greater than said first and said second high threshold, and is not lower than a first low threshold, but is lower than a second low threshold, and the percentage of said idle ones of said contention minislots is less than a second idle threshold, and said state value is “

2”

, increasing N by the number k, decreasing the number of dataslots by 1, and setting said state to “

1”

;

if said total uplink queue length is not greater than said first and said second high threshold and is lower than said first low threshold, and the percentage of said idle ones of said contention minislots is less than a second idle threshold, and said state value is “

1”

, increasing N by the number k, decreasing the number of dataslots by 1, and setting said state to “

0”

; and

if said total uplink queue length is not greater than said first and said second high threshold and is lower than said first low threshold, and the percentage of said idle ones of said contention minislots is less than said second idle threshold and said state value is “

2”

, increasing N by the number 2k, decreasing the number of dataslots by 2, and setting said state value to “

0”

.

5. The method of claim 2, wherein each of said uplink frames also contains a number of dataslots and wherein N has a minimum allowable value and a maximum allowable value, the value of N being dynamically adjusted by the steps of:

if the total length of all said uplink queues is greater than a high threshold, and the percentage of said idle ones of said contention minislots is greater than a first idle threshold, and if N is greater than said minimum allowable value, decreasing N by a number k and increasing the number of dataslots by 1; and

if the total length of all said uplink queues is not greater than said high threshold, and said total uplink queue length is less than a low threshold, and the percentage of said idle ones of said contention minislots is less than a second idle threshold, and N is less than said maximum allowable value, increasing N by the number k and decreasing the number of dataslots by 1.

6. The method of claim 2, wherein each of said uplink frames also contains a number of dataslots and wherein N has a minimum allowable value and a maximum allowable value, the value of N being dynamically adjusted by the steps of:

if the total length of all said uplink queues is greater than a first high threshold, and the percentage of said idle ones of said contention minislots is greater than a first idle threshold, and N is greater than said minimum allowable value, decreasing N by a number 2k and increasing the number of dataslots by 2;

if said total uplink queue length is not greater than said first high threshold, and said total uplink queue length is greater than a second high threshold, and the percentage of idle minislots is greater than said first idle threshold, and N is greater than the minimum number allowable, decreasing N by a number k and increasing the number of dataslots by 1;

if said total uplink queue length is not greater than said first high threshold and second high threshold, and is not lower than a first low threshold, but is lower than a second low threshold, and the percentage of said idle ones of said contention minislots is less than a second idle threshold, and N is less than the maximum allowable, increasing N by the number k and decreasing the number of dataslots by 1; and

if said total uplink queue length is not greater than said first high threshold and said second high threshold, and is lower than said first low threshold, and the percentage of said idle ones of said contention minislots is less than said second idle threshold, and N is less than the maximum allowable, increasing N by the number 2k and decreasing the number of said dataslots by 2.

7. The method of claim 1, further including the step of dynamically allocating a ratio of uplink to downlink transmission time based on a size of said downlink queue and information about a size of said remote host uplink queues received by said base station from said remote hosts.

8. The method of claim 1, wherein each of said uplink frames is associated with a content type, further including the step of assigning said access priority classes to said uplink frames based on said content type of said frames.

9. A method for access control in a wireless communications network, said network having a base station and a plurality of remote hosts between which uplink and downlink frames flow, said base station having a downlink queue, each of said remote hosts being characterized by a respective stack level and having an uplink queue, each of said uplink frames containing contention minislots, said contention minislots being organized into a plurality of access priority classes, each of said access priority classes being characterized by a different priority, the method comprising:

configuring a number N of said contention minislots of each of said uplink frames;

allowing for a number m of said plurality of access priority classes at said base station;

at each of said remote hosts having a stack level that equals 0 and being of an access priority class i, transmitting an access request with a probability P_i where P_(i+1)<

P_i and P_i=1 when i=1;

receiving at least one of said access requests at said base station;

identifying uncollided ones of said received access requests; and

granting access to one of said remote hosts that made an uncollided one of said access requests.

10. The method of claim 9, wherein a maximum value of N is dynamically adjustable based on the percentage of idle ones of said contention minislots and the combined lengths of all of said uplink queues.

11. The method of claim 10, wherein each of said uplink frames also contains a number of dataslots, the value of N being dynamically adjusted by the steps of:

if the total length of all said uplink queues is greater than a high threshold, and the percentage of said idle ones of said contention minislots is greater than a first idle threshold, and a state value is not “

1”

, decreasing N by a number k, increasing the number of dataslots by 1, and setting said state value to “

1”

; and

if the total length of all said uplink queues is not greater than said high threshold, and said total uplink queue length is less than a low threshold, and the percentage of said idle ones of said contention minislots is less than a second idle threshold and said state value is “

1”

, increasing N by the number k, decreasing the number of dataslots by 1, and setting said state value of “

0”

.

12. The method of claim 10, wherein each of said uplink frames also contains a number of dataslots, the value of N being dynamically adjusted by the steps of:

if the total length of all said uplink queues is greater than a first high threshold and the percentage of said idle ones of said contention minislots is greater than a first idle threshold and a state value if “

0”

, decreasing N by a number 2k, increasing the number of dataslots by 2, and setting said state value to “

2”

;

if the total length of all said uplink queues is greater than a first high threshold and the percentage of said idle ones of said contention minislots is greater than said first idle threshold and said state value is “

1”

, decreasing N by a number k, increasing the number of dataslots by 1, and setting said state value to “

2”

;

if said total uplink queue length is not greater than said first high threshold, and if said total uplink queue length is greater than a second high threshold and the percentage of said idle ones of said contention minislots is greater than said first idle threshold, and said state value is “

0”

, decreasing N by the number k, increasing the number of dataslots by 1, and setting said state value to “

1”

;

if said total uplink queue length is not greater than said first and said second high threshold, and is not lower than a first low threshold, but is lower than a second low threshold, and the percentage of said idle ones of said contention minislots is less than a second idle threshold, and said state value is “

2”

, increasing N by the number k, decreasing the number of dataslots by 1, and setting said state to “

1”

;

if said total uplink queue length is not greater than said first and said second high threshold and is lower than said first low threshold, and the percentage of said idle ones of said contention minislots is less than a second idle threshold, and said state value is “

1”

, increasing N by the number k, decreasing the number of dataslots by 1, and setting said state to “

0”

; and

if said total uplink queue length is not greater than said first and said second high threshold and is lower than said first low threshold, and the percentage of said idle ones of said contention minislots is less than said second idle threshold and said state value is “

2”

, increasing N by the number 2k, decreasing the number of dataslots by 2, and setting said state value to “

0”

.

13. The method of claim 10, wherein each of said uplink frames also contains a number of dataslots and wherein N has a minimum allowable value and a maximum allowable value, the value of N being dynamically adjusted by the steps of:

if the total length of all said uplink queues is greater than a high threshold, and the percentage of said idle ones of said contention minislots is greater than a first idle threshold, and if N is greater than said minimum allowable value, decreasing N by a number k and increasing the number of dataslots by 1; and

if the total length of all said uplink queues is not greater than said high threshold, and said total uplink queue length is less than a low threshold, and the percentage of said idle ones of said contention minislots is less than a second idle threshold, and N is less than said maximum allowable value, increasing N by the number k and decreasing the number of dataslots by 1.

14. The method of claim 10, wherein each of said uplink frames also contains a number of dataslots and wherein N has a minimum allowable value and a maximum allowable value, the value of N being dynamically adjusted by the steps of:

if the total length of all said uplink queues is greater than a first high threshold, and the percentage of said idle ones of said contention minislots is greater than a first idle threshold, and N is greater than said minimum allowable value, decreasing N by a number 2k and increasing the number of dataslots by 2;

if said total uplink queue length is not greater than said first high threshold, and said total uplink queue length is greater than a second high threshold, and the percentage of idle mini slots is greater than said first idle threshold, and N is greater than the minimum number allowable, decreasing N by a number k and increasing the number of dataslots by 1;

if said total uplink queue length is not greater than said first high threshold and said second high threshold, and is not lower than said a low threshold, but is lower than a second low threshold, and the percentage of said idle ones of said contention minislots is less than a second idle threshold, and N is less than the maximum allowable, increasing N by the number k and decreasing the number of dataslots by 1; and

if said total uplink queue length is not greater than said first high threshold and said second high threshold, and is lower than said first low threshold, and the percentage of said idle ones of said contention minislots is less than said second idle threshold, and N is less than the maximum allowable, increasing N by the number 2k and decreasing the number of dataslots by 2.

15. The method of claim 9, further including the step of dynamically allocating a ratio of uplink to downlink transmission time based on a size of said downlink queue and information about a size of said remote host uplink queues received by said base station from said remote hosts.

16. The method of claim 9, wherein each of said uplink frames is associated with a content type, further including the step of assigning said access priority classes to said uplink messages based on said content type of said messages.

17. A method for dynamic adjustment of a number of contention minislots available for access control in a wireless network, said network having a base station, and a plurality remote hosts between which uplink and downlink frames flow, said base station having a downlink queue, each of said remote hosts having an uplink queue, each of said uplink frames containing the number of contention minislots and a number of dataslots, the method comprising:

configuring the number of contention minislots N in each of said uplink frames;

dynamically adjusting the value of N by the steps of;

if the total length of all said uplink queues is greater than a high threshold, and the percentage of said idle ones of said contention minislots is greater than a first idle threshold, and a state value is not “

1”

, decreasing N by a number k, increasing the number of dataslots by 1, and setting said state value to “

1”

; and

if the total length of all said uplink queues is not greater than said high threshold, and said total uplink queue length is less than a low threshold, and the percentage of said idle ones of said contention minislots is less than a second idle threshold and said state value is “

1”

, increasing N by the number k, decreasing the number of dataslots by 1, and setting said state value to “

0”

.

18. A method for dynamic adjustment of a number of contention minislots available for access control in a wireless network, said network having a base station, and a plurality remote hosts between which uplink and downlink messages flow, said base station having a downlink queue, each of said remote hosts having an uplink queue, each of said uplink frames containing the number of contention minislots and a number of dataslots, the method comprising:

configuring the number of contention minislots N in each of said uplink frames;

dynamically adjusting the value of N by the steps of;

if the total length of all said uplink queues is greater than a first high threshold and the percentage of said idle ones of said contention minislots is greater than said first idle threshold and a state value is “

0”

, decreasing N by a number 2k, increasing the number of dataslots by 2, and setting said state value to “

2”

;

if the total length of all said uplink queues is greater than a first high threshold and the percentage of said idle ones of said contention minislots is greater than said first idle threshold and said state value is “

1”

, decreasing N by a number k, increasing the number of dataslots by 1, and setting said state value to “

2”

;

if said total uplink queue length is not greater than said first high threshold, and if said total uplink queue length is greater than a second high threshold and the percentage of said idle ones of said contention minislots is greater than said first idle threshold, and said state value is “

0”

, decreasing N by the number k, increasing the number of dataslots by 1, and setting said state value to “

1”

;

if said total uplink queue length is not greater than said first and said second high threshold, and is not lower than said a low threshold, but is lower than a second low threshold, and the percentage of said idle ones of said contention minislots is less than a second idle threshold, and said state value is “

2”

, increasing N by the number k, decreasing the number of dataslots by 1, and setting said state to “

1”

;

if said total uplink queue length is not greater than said first and said second high threshold and is lower than said first low threshold, and the percentage of said idle ones of said contention minislot is less than a second idle threshold, and said state value is “

1”

, increasing N by the number k, decreasing the number of dataslots by 1, and setting said state to “

0”

; and

if said total uplink queue length is not greater than said first and said second high threshold and is lower than said first low threshold, and the percentage of said idle ones of said contention minislots is less than said second idle threshold and said state value is “

2”

, increasing N by the number 2k, decreasing the number of dataslots by 2, and setting said state value to “

0”

.

19. A method for dynamic adjustment of a number of contention minislots available for access control in a wireless network, said network having a base station, and a plurality remote hosts between which uplink and downlink frames flow, said base station having a downlink queue, each of said remote hosts having an uplink queue, each of said uplink frames containing the number of contention minislots and a number of dataslots, the method comprising:

configuring the number of contention minislots N in each of said uplink frames, wherein N has a minimum allowable value and a maximum allowable value;

dynamically adjusting the value of N by the steps of;

if the total length of all said uplink queues is greater than a high threshold, and the percentage of said idle ones of said contention minislots is greater than a first idle threshold, and if N is greater than said minimum allowable value, decreasing N by a number k and increasing the number of dataslots by 1; and

if the total length of all said uplink queues is not greater than said high threshold, and said total uplink queue length is less than a low threshold, and the percentage of said idle ones of said contention minislots is less than a second idle threshold, and N is less than said maximum allowable value, increasing N by the number k and decreasing the number of dataslots by 1.

20. A method for dynamic adjustment of a number of contention minislots available for access control in a wireless network, said network having a base station, and a plurality remote hosts between which uplink and downlink messages flow, said base station having a downlink queue, each of said remote hosts having an uplink queue, each of said uplink frames containing the number of contention minislots and a number of dataslots, the method comprising:

configuring the number of contention minislots N in each uplink message, wherein N has a minimum allowable value and a maximum allowable value;

dynamically adjusting the value of N by the steps of;

if the total length of all said uplink queues is greater than a first high threshold, and the percentage of said idle ones of said contention minislots is greater than a first idle threshold, and N is greater than said minimum allowable value, decreasing N by a number 2k and increasing the number of dataslots by 2;

if said total uplink queue length is not greater than said first high threshold, and said total uplink queue length is greater than a second high threshold, and the percentage of idle minislots is greater than said first idle threshold, and N is greater than the minimum number allowable, decreasing N by a number k and increasing the number of dataslots by 1;

if said total uplink queue length is not greater than said first high threshold and said second high threshold, and is not lower than said a low threshold, but is lower than a second low threshold, and the percentage of said idle ones of said contention minislots is less than a second idle threshold, and N is less than the maximum allowable, increasing N by the number k and decreasing the number of dataslots by 1; and

if said total uplink queue length is not greater than said first high threshold and said second high threshold, and is lower than said first low threshold, and the percentage of said idle ones of said contention minislots is less than said second idle threshold, and N is less than the maximum allowable, increasing N by the number 2k and decreasing the number of dataslots by 2.

21. A method for paging in a wireless network, said network having a base station and a plurality of remote hosts between which uplink and downlink messages flow, each of said remote hosts being associated with a home registration server, comprising:

initiating a paging request at a first one of said remote hosts, said paging request being intended for a target one of said remote hosts;

identifying said home registration server of said target remote host;

relaying a call initiate message to said base station from said first remote host;

sending said call initiate message from said base station to a wireless modem with which said target remote host is associated;

relaying said call initiate message from said wireless modem to said target remote host;

accepting said call initiate message at said target remote host by sending a call accept message and a connect request message from said target remote host to said wireless modem;

responding from said wireless modem to said base station with said call accept message, as well as with said call request message if there is currently no connection between said wireless modem and said base station;

relaying a connect reply message from said home registration server to said target remote host; and

relaying said call accept message from said base station to said first remote host.

22. A method for access without contention in a communications network having a base station and supporting connection to plural classes of remote hosts, said base station maintaining a bandwidth reserved list of those of said remote hosts admitted to communication with said base station, said plural classes of remote hosts including at least one higher priority class and at least one lower priority class, said network supporting admission of a maximum total number of remote hosts, each of said remote hosts having an associated modem the method comprising the steps, in combination, of:

observing an empty input queue at the associated modem of an admitted one of said remote hosts belonging to a higher priority class;

triggering a timer having an interval of operation at said associated modem prior to any removal of said higher priority remote host from said bandwidth reserved list;

delaying any removal of said higher priority remote host from said bandwidth reserved list for at least said interval of operation of said timer, in order to allow for the potential arrival of additional packets; and

completing removal of said higher priority remote host from said bandwidth reserved list only if additional packets fail to arrive during said interval of operation of said timer.

23. A method for access control in a wireless communications network, said network having a base station and a plurality of remote hosts between which uplink and downlink frames flow, each of said uplink frames containing a number of contention minislots N, said contention minislots being organized into a plurality of access priority classes, each of said access priority classes being characterized by a different priority, the method comprising:

allowing for a number m of said plurality of access priority classes at said base station;

receiving, at said base station, at least one access request, wherein for a remote host of an access priority class i, said remote host has randomly picked one of said contention minislots in which to send said access request, said picked contention minislot being in a range from 1 to N_i where N_(i+1)<

N_i and N_i=N when i=1;

identifying uncollided ones of said received access requests; and

granting access to one of said remote hosts that made an uncollided one of said access requests.

24. A method for access control in a wireless communications network, said network having a base station and a plurality of remote hosts between which uplink and downlink frames flow, each of said uplink frames containing a number of contention minislots N, said contention minislots being organized into a plurality of access priority classes, each of said access priority classes being characterized by a different priority, the method comprising:

configuring a number N of said contention minislots in each of said uplink frames;

in at least one of said remote hosts of an access priority class i, randomly picking one of said contention minislots in which to send an access request, said picked contention minislot being in a range from 1 to N_i where N_(i+1)<

N_i and N_i=N when i=1; and

transmitting said access request from said remote host to said base station for determination of whether said access request is uncollided and access to said base station will be granted to the requesting remote.

25. A method for access control in a wireless communications network, said network having a base station and a plurality of remote hosts between which uplink and downlink frames flow, each of said remote hosts being characterized by a respective stack level, each of said uplink frames containing a number of contention minislots N, said contention minislots being organized into a plurality of access priority classes, each of said access priority classes being characterized by a different priority, the method comprising:

allowing for a number m of said plurality of access priority classes at said base station;

receiving, at said base station, at least one access request, wherein a remote host of an access priority class i and a stack level that equals 0, transmits an access request with a probability P_i where P<sub>(i+1)<

Pi</sub> and P_i=1 when i=1;

identifying uncollided ones of said received access requests; and

granting access to one of said remote hosts that made an uncollided one of said access requests.

26. A method for access control in a wireless communications network, said network having a base station and a plurality of remote hosts between which uplink and downlink frames flow, each of said remote hosts being characterized by a respective stack level, each of said uplink frames containing a number of contention minislots N, said contention minislots being organized into a plurality of access priority classes, each of said access priority classes being characterized by a different priority, the method comprising:

configuring a number N of said contention minislots in each of said uplink frames;

in at least one of said remote hosts of an access priority class i and a stack level that equals 0, transmitting an access request with a probability P_i where P_(i+1)<

P_i and P_i=1 when i=1; and

transmitting said access request from said remote host to said base station for determination of whether said access request is uncollided and access to said base station will be granted to the requesting remote.

27. A method for access without contention in a communications network having a base station and supporting connection to plural classes of remote hosts, said base station maintaining a bandwidth reserved list of those of said remote hosts admitted to communication with said base station, said plural classes of remote hosts including at least one higher priority class and at least one lower priority class, the method comprising:

observing, from said base station, an empty input queue for an admitted one of said remote hosts belonging to a higher priority class;

triggering a timer at said base station prior to any removal of said higher priority remote host from said bandwidth reserved list;

delaying any removal of said higher priority remote host from said bandwidth reserved list for at least said interval of operation of said timer; and

removing said higher priority remote host from said bandwidth reserved list only if additional packets fail to arrive during said interval of operation of said timer.