Software Defined Mobility Management for Mobile InternetSoftware Defined Mobile Networks Hector Alberto Fuentes Castillo

Agenda

1. Mobility Management in the Internet

2. Internet mobility overview

3. Problem in detail

4. Mobility management based on SDN

1. Existing research

2. Benefits of SDN based mobility

5. Software Defined Internet Mobility Management

1. Architecture overview

2. An open flow instantiation

3. Binding cache Placement Algorithm1. Evaluation, experiment and results

6. Summary

24.3.2016

2

Mobility Management in the Internet

24.3.2016

3

• Along with the growing of mobile data services

efforts on Internet mobility have been paid

• So far there is no consensus– Remains as an open issue

MMI and cellular networks

• Cellular networking has been providing mobility

• Why it may not suit Internet Mobility?

ISP handover

Inter device switching

• Trend to provide flexible & dynamic mobility management

• IP is considered as the core part of upcoming cellular networks

• LTE deployment has started in many markets: does not have circuit switched services

anymore

• Cellular networking is evolving toward IP- based designs (e.g. femtocells )

24.3.2016

4

Existing Internet Mobility solution• Internet mobility = Uninterrupted internet connectivity

• Candidates: many IP mobility solutions

• IETF released standards that may be adopted into 3GPP: Proxy Mobile IPv6 (EPC 3GPP)

• Challenge:

• Mobility contradicts current Internet architecture: Tight coupling of higher layer protocols with IP address:

• TCP sessions are identified by Source-IP-add, Source-port, dest-IP add and destport

• Approach categories:

1. Routing based -> Keep IP address

2. Mapping based -> Use identifier to resolve locator (IP address): Mobile IP protocols

24.3.2016

5

Integrating Internet mobility management and SDN• Despite of the various realizations of mobility management

they drawback different aspects: still an unsolved issue

• SDN emerging network architectural has a new approach:

• Network structures, functions and performance are defined simpler thanks to programmable devices and centralized control logic

• Network features required to support IP mobility can also be realized in software defined ways.

• Open Flow the most well known instantiation of SDN

24.3.2016

6

SDN helps to solve IP mobility protocols problems ?• Programmable devices provide flexibility

• Centralized control enables awareness of all mobility details

• IP mobility may require less host involvement under SDN

24.3.2016

7

Internet Mobility overview

• MIP and derivatives

• ILS designs

Internet mobility overview

1. Mobile IP

• IETF standards - Many derivatives (PMIP v6 )

- Standardization began two decades ago

2. Identifier/Locator Split ( ILS ) designs

• Relies on hosts to realize mobility management

• An IP address has embedded both identifier and locator - A concept also discussed widely in past decades

3. Other proposals on future Internet Architecture

• Substantial changes to the current Internet

24.3.2016

9

Mobile IP & derivatives• Minimal Handover Latency• No client software requirement ( in the case

of PMIPv6)• Extremely Light Weight Protocol, MAG

function can be implemented on a low-cost access point

• MIP centralizes mobility signalling and forwarding -> single Home Agent (HA)

• Increase signalling cost when out Home

network

• All packets from CN to MN have to go

through HA -> Triangle routing problem

• Thus heavy load for HAs

• Distributed Mobility Management (DMM)

• Multiple mobility anchors• HoA not a fixed location any more

*Under standardization

24.3.2016

10

1. ILS designs

24.3.2016

11

• Two categories:

– Separate edge and core add name spaces. Focused in

global routing *

– Entire IP space as locators: A namespace for identifiers

• Host based solutions (mobility

implemented at host side)

• Either introduce a new layer or modify

existing layer

• Host Identity Protocol (HIP)= DNS +

Rendezvous -> new layer above network

layer

• Identifier/Locator Network Protocol (ILNP) =

Split IP ->Modifies transport layer

• Name Based Sockets (NBS) = Domain

names ID-> new layer above transport layer

• LISP Mobile Node= Endpoint ID and Routing

locators (RLOC)->Lightweight tunnel routing

on each mobile host (avoids use of DNS)

*These are not in the scope of this slides

The same idea with different

formatting, implementation

and mapping functions

Problem in detail

24.3.2016

12

Mobility management analysis

Considering handoff management:

• Three categories:

• Local scope handoff : MIPs

• Global scope handoff : ILS designs

• Hybrid: DMM solutions *(under standardization at IETF)• Local scope handoff :propagate mapping to close HA

• Global scope handoff: propagate globally if HA has changed

• Packets are forwarded to an intermediary node close to MN

Similarities: All of them require MN to announce its up to date mapping to network

so that CN can reach it , directly(ILS) or indirectly (MIP)

24.3.2016

13

Routing path stretch and handoffefficiencyTrade off between routing path stretch and hand off latency

• Limited scope of mapping announcement reduce signalling

overhead and latency but CN loses exact location and has to

reach MN via indirection which may lead to routing path stretch.

• Mobile IP leads to routing path stretch (e.g. triangle routing)

• ILS heavy overhead and large latency

• DMM a balanced option? (Last draft: 2015-04-22 )• Future mobile users connect simultaneously to multiple ISP and switch between

them.

24.3.2016

14

Mobility management based on SDN

Existing research

• Open Roads

• Improve robustness of handoff with multicast Open Flow

• Improving basic IP mobility functions adopted by existing

protocols

• SDN/Open Flow in Virtualized LTE to support distributed

mobility management

24.3.2016

15

Benefits of SDN based mobility

1. Existing solutions with different trade-offs, and not really

flexible

2. A promising way to seek balance for the performance of the

trade off

3. Programmable devices are enabled as potential rendezvous

for MNs

1. No performing mapping announcement in arbitrary scope

2. Centralized control can define the scope

24.3.2016

16

Software Defined Internet Mobility Management The important for SDIMM:

Seek an algorithm that optimizes the

scope of mapping announcements

24.3.2016

17

• Architecture overview

24.3.2016

18

– Identifiers as in ILS

» Any format but a field in

packet devices can

recognize

– Locators of MNs

» IP address, normally

– Two control plane sub

functions:

» SDN controllers collect

current location of MN

» SDN controllers download

mapping in relevant SDN

devices (on request or

update)

An open flow instantiation

24.3.2016

19

Jun Bi and You Wang

Tsinghua University of Beijing, China

Protocol basis1. Locator ( CoA )

• IP address

2. Identifier ( HoA )

• IP address

3. OpenFlow controller

maintains binding cache

4. OpenFlow switches

1. Maintain replica of binding cache

2. Redirect packets to MN according flow table

• Inter domain handoff: long distance, tringle and the optimize

• Short distance: single logic

24.3.2016

20

Binding Cache Placement Algorithm

But in which switch (TS) place cache binding

• MN’s first hop = Triangle routing (like MIP)

• CN’s first hop = Large number of flow table download and

high latency (like HIP)

=>Binding Cache Placement Problem

24.3.2016

21

1. Goals

1. Optimal forwarding path

2. Minimize distance between MN and TS (Target Switch)

3. Minimize flow entry download per movement

BCPPs

• BCPP1

• Objective: goal 2

• Constrain: goal 1

• BCPP2

• Objective: goal 3

• Constrain: goal 1

24.3.2016

22

1. Evaluation

1. Algorithm proposed, assuming:

1. Intra domain scenario

2. MN to CN only relies in destination address

2. Algorithm random for each path pair of previous and current

path chose randomly any switch

3. Algorithm CN, For each pair of paths choose CN’s first hop

24.3.2016

23

Evaluation topology and routing data using intra domain topologies

24.3.2016

24

1. System design 1. Implementation on Mini net

1. IP reconfiguration is ignored (favour PIMIPv6 & ILNP)

24.3.2016

25

1. Experiment and results

24.3.2016

26

Conclusion

Experiment show advantage of SDN architecture due to:

• Centralized control

• Programmable devices

• In general SDN enables flexibility

• => Adaptive to various scenarios in future

mobile Internet

24.3.2016

27