Objective

Select the end-to-end video path (cache in the core and wireless technology in the

access network) which provides the best perceived quality to the user

Benefits

Keep enhanced QoE at the user side and optimize

network resources

Impacts

QoE

Offloading

Network load balancing

MULTIMEDIA TRAFFIC OPTIMIZATION IN LTE NETWORKS: A SIMULATIVE NS-3 BASED APPROACH

September 2012, Alcatel-Lucent Bell Labs, Paris

Objective

Design of novel communication schemes and their implementation via a network simulation tool to test and validate the MEDIEVAL approach

Tool

MEDIEVAL uses ns-3, an open source discrete-event network simulator for Internet-based systems. Specifically, a new module integrated in the latest stable

release of ns-3, LENA, has been used to simulate the LTE core network (EPC) and the radio access network, eUTRAN. The LENA project is designed in a

product -oriented fashion. It implements the Scheduling APIs defined by the Small Cell Forum, formerly Femto Forum.

EVALUATION OF JUMBO FRAMES IN LTE

U1

U3

U2 eNB

Scenario EPC architecture ns-3 scheme

Source

CN

9000 Bytes 1000 Bytes

eNB RLC

buffer

9000 Bytes 1000 Bytes

PDU size as a

function of the CQI

CQI

Technologies comparison Statistics for 450 MB video transmission

U1 U3 U2

Total overhead [MB]

U1 14.6 1.9

U2 15 2.3

U3 15.4 2.6

RLC Header size

Transmission Time [s] U1 182 177

U2 372 362

U3 520 506

U1

U3

U2 eNB

Scenario EPC architecture ns-3 scheme

Tunable

packet size

Extra data

storage

Source

eNB RLC

buffer

PDU size as a

function of the CQI

CQI

CN Buffer

packet size as a

function of the CQI

In a mobile scenario Jumbo Frames transmission

quickly saturates the available RLC buffer at the eNB,

causing packet dropping

The proposed scheme adapts, in a cross-layer manner,

the Jumbo packets directly in the CN according to the

channel quality perceived by each user

The buffer at the CN can be seen as an intermediate

storage level between the P-GW and the eNB

ONLINE VIDEO PATH SELECTION LTE RELAY AT PDCP LEVEL

Objective

extend the network beyond the eNodeB by forwarding

packets at PDCP level

Benefits

from MAC, RLC, PDCP features:

error recovery, transmission quality

Impacts

Radio Control procedures

Data forwarding in the relay

(increases effect of radio link on QoS metrics)

LTE RESOURCE ALLOCATION FOR SOFT QOS VIDEO TRAFFIC

Objective

Investigate the suitability of a soft QoS resource

allocator specifically tailored for multimedia content

Benefits

Provide best QoE to users making intensive use of

LTE resource blocks and scalable video coding

Impacts

Overall QoE

Pricing (user classes)

Enlarging set of user classes

Adaptive modulation and coding

Dynamic video coding

LTE access

WLAN access

CDN cache WLAN CDN cache LTE

Evolved Packet Core MAR

MAR

MAR

CDN cache LTE CDN cache WLAN

LTE access

WLAN access

9000 Bytes

Transmission buffer comparison

The capacity increases

steadly even when the

number of users is high

(multiuser phenomenon in

OFDM networks)

An upper limit to the utilization of

the available capacity is imposed

N users can be served at high

rate and M extra-users can be

served with a lower rate which

depends on M

Heuristic to allocate rate to users do not change

over time

Percentage of users to be served with base layer

or enhancement layer not configurable (i.e., static)

Programmability would give dynamicity to the

allocators allowing the network to react upon

overload and congestion

Objective

Validation of Jumbo Frames and architecture design for deployment in LTE networks

Jumbo Frames Technology Evaluation

· users are static

· Round Robin scheduler

· 3 regions (64 QAM, 16 QAM, QPSK)

The benefit of Jumbo Frames depends on the quality of the link and on the number of users served

Jumbo Frames avoid complex RLC concatenation achieving reduced header size for all the transmitted PDUs

The fixed region assigned to each user by the scheduler at the eNB suggests to adjust the dimension of the Jumbo Frames packets directly in the CN

Proposed architecture

· mobile users