custom enb scheduler and lessons learnt from oai development
TRANSCRIPT
![Page 2: Custom eNB Scheduler and lessons learnt from OAI development](https://reader034.vdocuments.us/reader034/viewer/2022042706/589dfe171a28ab1e718b6639/html5/thumbnails/2.jpg)
LTE eNB schedulers: the basics
MAC in eNB stack contains a scheduler for assigning time/frequency resource blocks to users, in downlink and uplink, compliant with 3GPP specification. It controls and prioritizes bandwidth across users.
(source: https://blog.yate.ro/2015/07/30/an-introduction-to-the-lte-mac-scheduler/)
![Page 3: Custom eNB Scheduler and lessons learnt from OAI development](https://reader034.vdocuments.us/reader034/viewer/2022042706/589dfe171a28ab1e718b6639/html5/thumbnails/3.jpg)
LTE eNB schedulers: the baseline
It’s fair to UEs in the long term, but isn’t aware of network conditions (like CQI) or specific UEs needs (like VoLTE). It’s regarded as inefficient in terms of cell throughput.
The simplest scheduling algorithm is Round Robin. It assigns resource blocks cyclically to all UEs, one after another.
It provides benchmark baseline.
Start
Schedule first user
Schedule next user
All users scheduled?Yes No
![Page 4: Custom eNB Scheduler and lessons learnt from OAI development](https://reader034.vdocuments.us/reader034/viewer/2022042706/589dfe171a28ab1e718b6639/html5/thumbnails/4.jpg)
LTE eNB schedulers: Proportional Fair
Properties:weighted by CQImaintains UEs throughput historyprioritizes UEs with lower throughputcell-edge users aren’t neglected
Proportional Fair algorithm is an example of achieving good cell throughput while being quite fair.
Start
Compare CQI
User withhigher CQI?
Schedule first user
Schedule next user
1st time slotfinished?
Schedule first user
Schedule next user
2nd time slotfinished?
No Yes
No
YesNo Yes
RR greedyPF
What we want:Proportional Fair
fairness & efficiencyour scheduler
fairness & efficiency<<
fairnesscell
throughputefficiency
LTE scheduling algorithms spectrum
![Page 5: Custom eNB Scheduler and lessons learnt from OAI development](https://reader034.vdocuments.us/reader034/viewer/2022042706/589dfe171a28ab1e718b6639/html5/thumbnails/5.jpg)
Advanced scheduler takes into account more properties.
We aim to provide good GBR instead of raw throughput. This should make better use of resources in real-life scenarios.
Advanced scheduler
![Page 6: Custom eNB Scheduler and lessons learnt from OAI development](https://reader034.vdocuments.us/reader034/viewer/2022042706/589dfe171a28ab1e718b6639/html5/thumbnails/6.jpg)
LTE eNB schedulers: implementation
But real world data → real eNB stack.
We used Small Cell Forum's Femto Application Platform Interface. Now scheduler is pluggable into any compliant stack. FAPI was enhanced to support Carrier Aggregation.EURECOM devs added partial FAPI support to OAI.We implemented Round Robin and Advanced schedulers in ANSI C, as libraries and are integrating them with OAI.
+ LTE MAC Lab → performance estimates.Models in
was a natural choice.
![Page 7: Custom eNB Scheduler and lessons learnt from OAI development](https://reader034.vdocuments.us/reader034/viewer/2022042706/589dfe171a28ab1e718b6639/html5/thumbnails/7.jpg)
Standard interfaces are a Good Thing
(source: Small Cell Forum)
![Page 8: Custom eNB Scheduler and lessons learnt from OAI development](https://reader034.vdocuments.us/reader034/viewer/2022042706/589dfe171a28ab1e718b6639/html5/thumbnails/8.jpg)
Advanced scheduler: estimates
![Page 9: Custom eNB Scheduler and lessons learnt from OAI development](https://reader034.vdocuments.us/reader034/viewer/2022042706/589dfe171a28ab1e718b6639/html5/thumbnails/9.jpg)
Advanced scheduler: estimates
![Page 10: Custom eNB Scheduler and lessons learnt from OAI development](https://reader034.vdocuments.us/reader034/viewer/2022042706/589dfe171a28ab1e718b6639/html5/thumbnails/10.jpg)
Lessons learnt
Some after-action thoughts from our devs about working with OAI:
setting up development environment for OAI is time consuming and prone to error - needs more automationit’s hard for non-Linux-savvy devs to get basic usecases working – one-click solution would be idealOAI would benefit from a simpler way to manage its configuration
To address those needs we created a new set of productivity tools, which wrap around OAI and allow for rapid deployment of basic usage scenarios, make reconfiguration easy and save a lot of time: aLTErnative.
![Page 11: Custom eNB Scheduler and lessons learnt from OAI development](https://reader034.vdocuments.us/reader034/viewer/2022042706/589dfe171a28ab1e718b6639/html5/thumbnails/11.jpg)
aLTErnative walkthrough
For novices there's interactive GUI.
![Page 12: Custom eNB Scheduler and lessons learnt from OAI development](https://reader034.vdocuments.us/reader034/viewer/2022042706/589dfe171a28ab1e718b6639/html5/thumbnails/12.jpg)
For power users there's script-friendly command line.
aLTErnative walkthrough
![Page 13: Custom eNB Scheduler and lessons learnt from OAI development](https://reader034.vdocuments.us/reader034/viewer/2022042706/589dfe171a28ab1e718b6639/html5/thumbnails/13.jpg)
There can be multiple profiles. Each profile has separate set of configuration files (eNB, MME, HSS) and own SIM database. In one place for easy reference. Starting from clean state is as easy as creating new profile.
aLTErnative walkthrough
![Page 14: Custom eNB Scheduler and lessons learnt from OAI development](https://reader034.vdocuments.us/reader034/viewer/2022042706/589dfe171a28ab1e718b6639/html5/thumbnails/14.jpg)
Adding SIMs to HSS is easy.
aLTErnative walkthrough
![Page 15: Custom eNB Scheduler and lessons learnt from OAI development](https://reader034.vdocuments.us/reader034/viewer/2022042706/589dfe171a28ab1e718b6639/html5/thumbnails/15.jpg)
Making OAI's eNB and core network work is easy too.
aLTErnative walkthrough
![Page 16: Custom eNB Scheduler and lessons learnt from OAI development](https://reader034.vdocuments.us/reader034/viewer/2022042706/589dfe171a28ab1e718b6639/html5/thumbnails/16.jpg)
Additionally aLTErnative offers a way to:setup your system for OAI development through a scriptgather logs and system information in a unified wayuse its components in your own applications through an API
It works on Ubuntu, can be installed and updated easily through its Software Center.
We have a lot of plans for extending aLTErnative:support for UEssupport for other open source LTE stacksnicer GUI
We believe aLTErnative has a lot to offer for OAI community.
aLTErnative
![Page 17: Custom eNB Scheduler and lessons learnt from OAI development](https://reader034.vdocuments.us/reader034/viewer/2022042706/589dfe171a28ab1e718b6639/html5/thumbnails/17.jpg)
THANK YOU
![Page 18: Custom eNB Scheduler and lessons learnt from OAI development](https://reader034.vdocuments.us/reader034/viewer/2022042706/589dfe171a28ab1e718b6639/html5/thumbnails/18.jpg)
IS-Wirelessul. Puławska 45b,
05-500 Piaseczno / near Warsaw,
Poland, EU
phonefax
webe-mail
+48 22 213 8297+48 22 213 [email protected]
CONTACT DETAILS