5G Network Architecture and the

Future Mobile Internet

IEEE 5G Workshop

Princeton, May 26, 2015

D. Raychaudhuri

WINLAB, Rutgers University

ray@winlab.rutgers.edu

Introduction

WINLAB

Introduction: 5G Vision

Faster radio ~Gbps

Low-latency wireless access ~ms

Dynamic spectrum, multiple radio access technologies

Next-gen network with improved support for emerging

mobility services:

Mobile Data

(cellular, hetnet)

Vehicular Networks Content Delivery

Cloud Services

Internet-of-Things Emergency Networks

WINLAB

Introduction: Why 5G Needs a New

Network Architecture

Hybrid 3GPP & IP arch

Complex control interfaces!

Technology specific

IP tunneling in data path

Gateways (..bottlenecks, sub-

optimum routing,..)

SGW

MME

PGW

MSC

PCRF

HSS

4G Radio

Access

Network

Internet

WAG

AAA

LTE

WiFi

Mobility-Centric

Future Internet

Architecture

LTE

w/FIA

interface

WiFi

w/FIA

interface

Standard FIA

Router

FIA Distributed

Control Plane

Unified Internet/Mobile Net arch with

integrated support for naming,

authentication, mobility, etc.

Simplified distributed control!

Technology neutral –BS or AP plug-in

Flat! No gateways or tunnels!

Mobile devices as “first class” citizens

TODAY 5G/NGMN/FIA

WINLAB

Introduction: Why the Internet needs a new

mobility-centric protocol architecture

Historic shift from PC’s to mobile computing and embedded devices… Mobile data growing exponentially – 3.6 Exabytes

in 2014, >> wired Internet traffic

Sensor/IoT/V2V ~5-10B units by 2020

Internet in 2020 all about mobile platforms &

services

Inevitable convergence of mobile

network and Internet industries Need to think beyond the “G”’s, associated with

linear progression in mobile systems

Era of vertically integrated protocol stacks built on

radio standards coming to an end

Single end-to-end protocol standard for the future

mobile Internet!

Research Target of NSF Future Internet

Architecture (FIA) MobilityFirst Project

Wireless Technology

Trend “5G”

Internet Technology

Trend “FIA”

Future

“Mobile Internet”

New wireless/mobile

functions, enhanced

security, services

Higher speeds/scale,

“network of networks”

Same end users!

WINLAB

Introduction: What a Converged Mobile

Internet Protocol Would Look Like…

Mobility was added to IP after the fact due to historical reasons, but single unified solution remains feasible Previous attempts at convergence such as mobile IP proved to be insufficient…

5G is an opportunity for the industry to address this need with a single unified protocol stack for all

services on the Internet, given that mobile is now the dominant use case

Can provide significant improvements: radio technology neutral, improved scalability and security, “flat”

network structure, enhanced mobility functions, …

TP

FIA IP+

xG PHY

xG MAC xG MAC

xG PHY

DLC

PHY

DLC

TP

PHY

DLC

FIA IP+ FIA IP+ FIA IP+ FIA IP+

PHY

UE BS/AP Router Router

Server

Internet Protocol

Future Internet Protocol with Integrated Mobility Support

Custom Access Protocols

Radio access specific

TODAY 5G/NGMN/FIA

Next-Gen Mobile Network

Requirements

WINLAB

Next-Gen Network Requirements: (1) Mobility

End-point mobility as a basic service of the future Internet

Any network connected object or device should be reachable on an efficiently

routed path as it migrates from one network to another

Eliminate service gateways (bottleneck points), IP tunnels, etc. (“flat”)

Fast authentication, dynamic handoff (vertical), and global roaming

Mobility service should be scalable (billions of devices) and fast ~50-100 ms

Implications for core naming/routing/security architecture of Internet

INTERNET

AS99

(LTE)

AS2

User/Device

Mobility

AS49

AS39

(WiFi

)

Inter-AS Roaming

Agreement

“Mobile Peering”

Measured Inter-Network Mobility Traces

(Prof. J. Kurose, UMass, 2013)

WINLAB

Next-Gen Network Requirements :

(2) Handling Disconnection & BW Variation Wireless medium has inherent fluctuations in bit-rate (as much

as 10:1 in 4G access), heterogeneity and disconnection Poses a fundamental protocol design challenge

New requirements include in-network storage/delay tolerant delivery, dynamic rerouting (late binding), etc.

Transport layer implications end-to-end TCP vs. hop-by-hop

INTERNET

Wireless

Access Net #3

Wireless

Access

Network #2

BS-1

AP-2

Mobile devices with varying BW due to SNR variation,

Shared media access and heterogeneous technologies

Time Disconnection

interval

Bit

Rate

(Mbps)

Dis-

connect

AP-2

BS-1

WINLAB

Next-Gen Network Requirements:

(3) Multicast as a Basic Service Many mobility services (content, context) involve multicast

The wireless medium is inherently multicast, making it possible to reach multiple end-user devices with a single transmission

Fine-grain packet level multicast desirable at network routers

INTERNET

Session level Multicast Overlay (e.g. PIM-SIM)

Wireless

Access Net #11

INTERNET

Access

Network

(Eithernet)

Radio

Broadcast

Medium

Packet-level Multicast at Routers/AP’s/BSs

RP

Wireless

Access

Net #32

Pkt Mcast at Routers

WINLAB

Wireless

Access Net #3

Next-Gen Network Requirements :

(4) Multi-Homing as a Standard Feature Multiple/heterogeneous radio access technologies (e.g.

4G/5G and WiFi) increasingly the norm Improved service quality/capacity via opportunistic high BW access

Improved throughput in hetnet (WiFi/small cell + cellular) scenarios

Can also be used to realize ultra-high bit-rate services using multiple technologies, e.g. 60 Ghz supplement to LTE

Implications for naming and routing in the Internet

INTERNET

Wireless

Access Net #3

Wireless

Access

Network

#2

LTE BS

WiFi

AP

Multihomed devices may utilize two or more interfaces to improve communications

quality/cost, with policies such as “deliver on best interface” or “deliver only on WiFi”

or “deliver on all interfaces”

Mobile device

With dual-radio NICs

60 Ghz BS

(supplement to LTE)

Multiple

Potential

Paths

WINLAB

Next-Gen Network Requirements:

(5) Efficient Content Delivery

Content Owner’s

Server

In-network cache

Get (“content_ID”) Send(“content_ID”, “user_ID”))

In-network

cache

Alternative paths

for retrieval

or delivery

Delivery of content to/from mobile devices a key service requirement in future networks (…”ICN”, etc.)

This requirement currently served by overlay CDN’s

In-network support for content addressability and caching is desirable service primitives such as get(content-ID, ..)

WINLAB

Context-aware delivery associated with mobile services, M2M Examples of context are group membership, location, network state, …

Requires framework for defining and addressing context (e.g. “taxis in New

Brunswick”)

Anycast and multicast services for message delivery to dynamic group

Mobile

Device

trajectory

Context = geo-coordinates & first_responder

Send (context, data)

Context-based

Multicast delivery

Context

GUID

Global Name

Resolution service

ba123

341x

Context

Naming

Service

NA1:P7, NA1:P9, NA2,P21, ..

Next-Gen Network Requirements:

(6) Context-Aware Services

WINLAB

Next-Gen Network Requirements: (7) Edge

Cloud Services

User Mobility

Edge Cloud

Service

A

Edge Cloud

Service

B

“Nearest” Cloud Service

Low latency, dynamic migration

Mobile Internet

Access Network A

Access Network B

Efficient, low-latency cloud services important for emerging

mobile data and cyber physical applications Tight integration of cloud service with access network

Service “anycast” primitive – get(service_ID,..)

Low latency, dynamic migration of state

Option for in-network processing in data plane

Get(“service_ID, data)

WINLAB

Access

Network

)

Next-Gen Network Requirements:

(8) Edge Peering and Ad Hoc Networks Wireless devices can form ad hoc networks with or without

connectivity to the core Internet

These ad hoc networks may also be mobile and may be capable of peering along the edge

Requires rethinking of inter-domain routing, trust model, etc. Ad Hoc Network Formation, Intermittent Connection to Wired Internet & Network Mobility

INTERNET

Access

Network

)

V2V Network

V2I

WINLAB

Next-Gen Network Requirements: Summary

Security related functions: authentication, data security, etc.

Mobility related functions: end-point migration, network mobility, in-

network storage/delay tolerance, edge awareness, ad-hoc modes,…

Multiple interface related functions: separation of object names from

network addresses, multi-homing, multi-path, …

Content & context support: named content retrieval, context-

specified dynamic multicast, in-network caching, …

In-network processing (optional): media transcoding, cloud services,

data aggregation, ..

From today’s

connection oriented

IP services

(“pipes”) …

To more general

set of service

abstractions

named objects, data

Open (IP_address, data)

Get (service)

service

Send (names, data)

From Vision to Proof-of-

Concept Realization:

MobilityFirst Architecture

WINLAB

MobilityFirst Design: Architecture Features

Routers with Integrated

Storage & Computing Heterogeneous

Wireless Access

End-Point mobility

with multi-homing In-network

content cache

Network Mobility &

Disconnected Mode

Hop-by-hop

file transport Edge-aware

Inter-domain

routing

Named devices, content,

and context

11001101011100100…0011

Public Key Based

Global Identifier (GUID)

Storage-aware

Intra-domain

routing

Service API with

unicast, multi-homing,

mcast, anycast, content

query, etc.

Strong authentication, privacy

Ad-hoc p2p

mode

Human-readable

name

Connectionless Packet Switched Network

with hybrid name/address routing

WINLAB

MF Design: Protocol Stack

IP

Hop-by-Hop Block Transfer

Link Layer 1

(802.11)

Link Layer 2

(LTE)

Link Layer 3

(Ethernet)

Link Layer 4

(SONET)

Link Layer 5

(etc.)

GSTAR Routing MF Inter-Domain

E2E TP1 E2E TP2 E2E TP3 E2E TP4

App 1 App 2 App 3 App 4

GUID Service Layer Narrow Waist GNRS

MF Routing

Control Protocol

NCS Name

Certification

& Assignment

Service

Global Name

Resolution

Service

Data Plane Control Plane

Socket API

Switching

Option

Optional Compute

Layer

Plug-In A

WINLAB

MF Design: Name-Address Separation

GUIDs Separation of names (ID) from

network addresses (NA)

Globally unique name (GUID)

for network attached objects User name, device ID, content, context,

AS name, and so on

Multiple domain-specific naming

services

Global Name Resolution Service

for GUID NA mappings

Hybrid GUID/NA approach Both name/address headers in PDU

“Fast path” when NA is available

GUID resolution, late binding option

Globally Unique Flat Identifier (GUID)

John’s _laptop_1

Sue’s_mobile_2

Server_1234

Sensor@XYZ

Media File_ABC

Host

Naming

Service

Network

Sensor

Naming

Service

Content

Naming

Service

Global Name Resolution Service

Network address

Net1.local_ID

Net2.local_ID

Context

Naming

Service

Taxis in NB

WINLAB

MF Design: Hybrid GUID/NA Storage

Router in MobilityFirst

GUID-Address Mapping – virtual DHT table

NA Forwarding Table – stored physically at router

GUID NA

11001..11 NA99,32

Dest NA Port #, Next Hop

NA99 Port 5, NA11

GUID –based forwarding

(slow path)

Network Address Based Forwarding

(fast path)

Router

Storage

Store when:

- Poor short-term path quality

- Delivery failure, no NA entry

- GNRS query failure

- etc.

NA32 Port 7, NA51

DATA

SID GUID=

11001…11 NA99,NA32

NA62 Port 5, NA11

To NA11

To NA51

Look up GUID-NA table when:

- no NAs in pkt header

- encapsulated GUID

- delivery failure or expired NA entry

Look up NA-next hop table when:

- pkt header includes NAs

- valid NA to next hop entry

DATA

DATA

Hybrid name-address based routing in MobilityFirst requires a new

router design with in-network storage and two lookup tables:

“Virtual DHT” table for GUID-to-NA lookup as needed

Conventional NA-to-port # forwarding table for “fast path”

Also, enhanced routing algorithm for store/forward decisions

WINLAB

MF Protocol Example: Mobility Service via

Name Resolution at Device End-Points

MobilityFirst Network

(Data Plane)

GNRS

Register “John Smith22’s devices” with NCS

GUID lookup

from directory

GUID assigned

GUID = 11011..011

Represents network

object with 2 devices

Send (GUID = 11011..011, SID=01, data)

Send (GUID = 11011..011, SID=01, NA99, NA32, data)

GUID <-> NA lookup

NA99

NA32

GNRS update

(after link-layer association)

DATA

SID

NAs

Packet sent out by host

GNRS query

GUID

Service API capabilities:

- send (GUID, options, data)

Options = anycast, mcast, time, ..

- get (content_GUID, options)

Options = nearest, all, ..

Name Certification

Services (NCS)

WINLAB

MF Protocol Example: Handling Disconnection

Data Plane

Send data file to “John Smith22’s

laptop”, SID= 11 (unicast, mobile

delivery)

NA99

NA75

Delivery failure at NA99 due to device mobility

Router stores & periodically checks GNRS binding

Deliver to new network NA75 when GNRS updates

GUID NA75

DATA

GUID NA99 rebind to NA75

DATA

DATA

GUID SID

DATA

SID GUID

NA99

Device

mobility

Disconnection

interval

Store-and-forward mobility service example

WINLAB

MF Protocol Example: Dual Homing Service

Data Plane

Send data file to “John Smith22’s

laptop”, SID= 129 (multihoming –

all interfaces)

NA99

NA32

Router bifurcates PDU to NA99 & NA32

(no GUID resolution needed)

GUID NetAddr= NA32

DATA

GUID NetAddr= NA99

DATA

DATA

GUID SID

DATA

SID GUID=

11001…11 NA99,NA32

DATA

Multihoming service example

WINLAB

MobilityFirst network evaluation for dual-homing • Parametric analysis of best interface vs. dual homing

• Link delay, data rate and download size varied

• Soft threshold to stripe across both interfaces or use best

Example Dual-Homing Result for MF:

Cellular LTE + WiFi Performance

-122.43 -122.42 -122.41 -122.4 -122.39 -122.38 -122.37

37.77

37.775

37.78

37.785

37.79

37.795

37.8

Longitude

La

titid

e

Free Wi-Fi hotspots(AT&T HotSpot Locator)

Simulation of San-Francisco cabs for Wi-Fi /LTE dual-homing

1 2 3 4 50

10

20

30

40

50

60

70

Ave

rag

e th

rou

gh

pu

t p

er

se

c (

in M

bp

s)

Cab no.1 2 3 4 5

0

10

20

30

40

50

60

70

Cab no.

Ma

xim

um

th

rou

gh

pu

t p

er

se

c (

in M

bp

s)

Using only LTE

Using the best available Wi-Fi

Using all the available WiFis

Using all the Wi-Fis and LTE

Only Wi-Fidoes not helpon an average

Dual-Homed

Mobile Device

(WiFI + LTE)

WINLAB

MF Proof-of-Concept Prototype: Click

Software Router and Android API

5/26/2015 WINLAB, Rutgers University 26

26

Click-based MF Router

- Storage-aware routing (GSTAR) - Name resolution (GNRS) - Reliable hop-by-hop link transport (Hop)

Android/Linux MF Protocol Stack

- Network API - Hop transport - Dual homing (WiFi/WiMAX)

WiMAX BTS

WiFi AP

Native,

user-level

implementation

on Android

runtime

MF Router

MF Router

MF Router

WINLAB

MF Proof-of-Concept: Deployment on

GENI

Salt Lake, UT

Cambridge,

MA

N. Brunswick,

NJ

Ann Arbor, MI Madison, WI

Tokyo, Japan

Lincoln, NE

Los Angeles,

CA Clemson,

SC

Long-term (non-

GENI)

MobilityFirst Access

Net

Short-term

Wide Area ProtoGENI

Palo Alto, CA

ProtoGENI

MobilityFirst

Routing and Name

Resolution

Service Sites

I2

NL

R

Atlanta, GA

MF Services Demonstrated on GENI:

Multi-Homing Mobile

Named Content Delivery

In-network Compute Service

Context-Aware Message Delivery

Edge-Aware Inter-Domain Routing

Global Name Resolution

… and others

Early adopter trials starting in 2015

Concluding Remarks

WINLAB

Concluding Remarks: 5G and the Next-Gen

Mobile Network Architecture

5G Radio

Wideband Cognitive Radio

Programmable OpenFlow SDN Switch

Multi-Radio Android Device Next-Gen Network

60 Ghz 802.11ad

“5G” Enabling

Technologies

Many new enabling technologies, but the key to 5G will be the

network architecture

Inevitable convergence of wireless access networks with the Internet

Highly functional new protocol design needed to support advanced mobility services

From connection-oriented “pipes” to flexible connectionless service abstractions

NSF FIA “MobilityFirst” architecture serves as proof-of-concept ….

Open LTE

??

Historic opportunity & risk for wireless and

networking industries!

WINLAB

Resources

Project website: http://mobilityfirst.winlab.rutgers.edu

GENI website: www.geni.net

ORBIT website: www.orbit-lab.org