Scalable Point-to-multipoint Communication Information-

centricNetworking

January, 2015

Börje OhlmanEricsson Research

Anders Eriksson, Karl-Åke Persson, Adeel Mohammad Malik, Marcus Ihlar and Linus Sunde

NetInf| Ericsson Internal | 2014-05-26 | Page 2

Why SPIN?Scalable Point-to-Multipoint Mechanism for Information-centric Networks (SPIN)

› Most existing ICN approaches require a new global ICN routing mechanism to route based on the names of information objects.

– A new global name-based routing system raises concerns regarding migration and scalability.

› In contrast SPIN:– avoids name-based routing or IP multicast routing by making use of legacy

IP unicast routing combined with DNS– supports two types of service models

› publish-subscribe› request aggregation

– support client and server mobility› DNS interacts with an additional Name Resolution System (NRS) which

resolves the name of an information object to a current locator of a representation of the information object.

NetInf| Ericsson Internal | 2014-05-26 | Page 3

Point-to-multipoint as a Network Service

WHAT› Scalable point-to-multipoint distribution

of pre-recorded content or real-time data for e.g. IoT or live video

› Application-independent › Scales to very large numbers of clients

HOW› Based on legacy IP routing› New name resolution system as a complement to DNS› Small modifications of CoAP, or a new NetInf protocol› Introduction of packet interception, pub-sub, and cache functions in

edge routers

WHY› Allows operators to add value, since the service is integrated in

edge routers and cannot be built as an OTT service

IP Network

Server

Client Client Client Client

ICN

ICN ICN

local peer-to-peer

NetInf| Ericsson Internal | 2014-05-26 | Page 4

Subscription State

SubscriberClient

Publisher Server

Request Subscribe

Response Notification 1

Response Notification N

Cancel

Publish-Subscribe

NetInf| Ericsson Internal | 2014-05-26 | Page 5

global IP network

NER 1 NER 2

NER 3

Pub

RSMNDO

SubSub

event notification

subscribe request

publication

subscribe request acknowledgement

DNS

NRS

SubSub

Pub-Sub & Event Notification Service

SMNDO SMNDO

› Point-to-multipoint distribution of notifications to subscribers in near real-time

› Application-independent› Can be used for video distribution or

IoT› Scales to millions of subscribers› Allows operators to add value, since

this is not an OTT service› Can be built with small modifications

of existing protocols (HTTP and Coap) and with legacy IP routing

Publish binding: FQDN / label -> IP address

Resolve: FQDN / label -> IP address

Name format: FQDN / label

NER NetInf Edge Router

NetInf| Ericsson Internal | 2014-05-26 | Page 6

Use of Tokens to Match Responses to Intercepted Requests With Original Request

Client Int-1 Int-2 Server

Address AC Address A1 Address A2 Address AS

1: Req(AC , AS, t1)

2: Req(A1 , AS, t2)

3: Req(A2 , AS, t3)

4: Resp(AS , A2, t3)

5: Resp(A2 , A1, t2)

6: Resp(A1 , AC, t1)

NetInf| Ericsson Internal | 2014-05-26 | Page 7

Signalling sequence for set-up of a point-to-multi-point tree

An IP addressC ClientIOx Information Object xR Information-centric RouterS Server Request Response

R1

C1 C2

S1

R21: Req

(AC1 , AS, t1)

2: Req(A21 , AS, t3)

3: Req(A11 , AS, t4)

4: Resp(AS , A11, t4)

5: Resp(A12 , A21, t3)

6a: Resp(A22 , AC1, t1)

6b: Resp(A23 , AC2, t2)

1: Req(AC2 , AS, t2)

A11

A12

A21

A22 A23

AS

AC1 AC2

IOx

NetInf| Ericsson Internal | 2014-05-26 | Page 8

Combining connectionless and Connection Oriented Signalling

Client 1Client 2 ICN Router

Publishing Server

Subscription Request 1

Subscription Request 3

Subscription Request 2

Notification Response 1 Notification Response 2

Notification Response 3HTTP GET Request 1

HTTP Response 1

HTTP GET Request 2

HTTP GET Request 3

HTTP Response 2

HTTP Response 3

NetInf| Ericsson Internal | 2014-05-26 | Page 9

Token Matching

Int-1Address A1

1: Req(AC , AS, t1) 2: Req(A1 , AS, t2)

5: Resp(A2 , A1, t2)6: Resp(A1 , AC, t1)

R T

S2S1

T R

Match

Match

Address & token

Construct request

Construct response

Receive and store 1: Req(AC , AS , t1)

Construct, store, bind to 1, and send2: Req(A1 , AS , t2)

Receive5: Resp(A2 , A1 , t2)

Match5: Resp(A2 , A1 , t2)

with 2: Req(A1 , AS , t2)

Match2: Req(A1 , AS , t2)

with1: Req(AC , AS , t1)

Construct and send6: Resp(A1 , AC , t1)

a

b

c

d

e

f

NetInf| Ericsson Internal | 2014-05-26 | Page 10

NetInf NODE Protocol Stack Using Legacy IP Routing

IP

UDP

NetInf/CoAP

NetInf / COAP API

IP

UDP

NetInf/CoAP

NetInf Node Functions

• pub/sub

• event notification

• request aggregation

• caching

• name-based routing

transit packets

NetInf / CoAP requests and responses

intercept

IP Network

Publisher

Sub Sub Sub Sub

A

A ADNS

NRS

NRS Name Resolution System

NetInf functions

NetInf| Ericsson Internal | 2014-05-26 | Page 11

Example Use Case prototyped and Evaluated› Live Video Streaming

– We show that a NetInf implementation of SPIN in request aggregation mode can handle flash crowds very well, can scale to unlimited number of users

– Request aggregation is best suited for use cases where each IO is (normally) only requested once and the client can (roughly) predict when it will become available

› Sensor networking– With the pub/sub model the sensor can publish new readings as they

become available, no need to respond to periodic requests. It can even go offline in-between publications

– Publish/Subscribe is best used when the publications are time series and/or published infrequently at unpredictable times (e.g. fire alarms) and/or when the publisher is only intermittently online

NetInf| Ericsson Internal | 2014-05-26 | Page 12

NetInf/SPIN Request Aggregation

NetInf Access network

NetInf network

Streamingnode

NetInfrouter

Cache

NetInfrouter

Cache

NetInfrouter

Cache

Reques

t(

)

Respo

nse(

)

CPU utilization as a function of the number of clientsmeasured on routers R1, R2 and R3

Cache hit region with traditional http proxy

Cache hit region with request aggregation proxy

Measured values with traditional http proxy

Measured values with request aggregation proxy

Cache hit limitTraditional HTTP caching vs. request aggregation

NetInf| Ericsson Internal | 2014-05-26 | Page 15

R2

R1

CP

U L

oad

(M

Hz)

CPU load in ICN routers R1 and R2 as a function of the number of subscribers

NetInf| Ericsson Internal | 2014-05-26 | Page 16

Conclusions and Future Work

› Key take a ways:– SPIN support both request aggregation and publish/subscribe – SPIN can support flash crowds without network provisioning,

something not possible in today’s IP networks– Use IP unicast routing both for forwarding requests and for retrieving

objects

› Future Work– Access control using Attribute Based Encryption (ABE)– Cut-through forwarding