Project

General

Profile

Feature #1611

be more efficient in batching IMMEDIATE ASSIGN REJECT messages

Added by laforge almost 2 years ago. Updated about 1 month ago.

Status:
New
Priority:
Normal
Assignee:
sysmocom
Category:
A-bis RSL
Target version:
-
Start date:
02/23/2016
Due date:
% Done:

0%

Spec Reference:

Description

The RR Immediate Assignment Reject message can handle up to fourr identities that are rejected in a single message.

We currently use one message per identiry, wasting downlink AGCH capacity.

I think this feature is relevant particularly in cases where many
REJECTs are expected, i.e. where many phones are around that are not
permitted to join. Think of a private/small GSM networrk in an area
where there is no (good) public network coverage, but where lots of
regular subscribers of the other operators pass by. Or in situations
where the public network fails, forcing all the phones to try to
register on the private/small network running OpenBSC.

The problem is actually amplified, as
  • we waste one entire 23 byte MAC block for rejecting only a single subscriber
  • We don't scale the AGCH up by means of BS_AG_BLKS_RES
    Both of the features above would enable rejecting more phones (with
    permanent reject cause) ensuring they don't overload RACH+AGCH on the
    cell.

Related issues

Related to OsmoBSC - Feature #2592: Use "waiting time" of IMMEDIATE ASSIGN REJECT New 10/23/2017
Related to OsmoBTS - Bug #1575: Correctly handle BS_AG_BLKS_RES (AGCH/PCH split in DL CCCH) Stalled 02/23/2016
Related to OsmoBSC - Feature #2722: document RACH tuning parameters more thoroughly, give explanations New 12/08/2017

History

#1 Updated by laforge 5 months ago

#2 Updated by laforge 3 months ago

  • Assignee set to sysmocom

#3 Updated by laforge 3 months ago

  • Related to Feature #2592: Use "waiting time" of IMMEDIATE ASSIGN REJECT added

#4 Updated by laforge 3 months ago

  • Related to Bug #1575: Correctly handle BS_AG_BLKS_RES (AGCH/PCH split in DL CCCH) added

#5 Updated by laforge 3 months ago

#6 Updated by laforge about 1 month ago

  • Related to Feature #2722: document RACH tuning parameters more thoroughly, give explanations added

#7 Updated by laforge about 1 month ago

  • Project changed from OpenBSC to OsmoBSC
  • Category deleted (libbsc)

#8 Updated by laforge about 1 month ago

  • Category set to A-bis RSL

Also available in: Atom PDF