HSN ‘98‘98.2.12 ~ 14, 전주

1

IP over Wireless ATM

1998. 2. 13.

김 용 진

한국전자통신연구원

HSN ‘98‘98.2.12 ~ 14, 전주

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Outline

Background Mobile IP IP over ATM Location Management in WATM IP over Wireless ATM

HSN ‘98‘98.2.12 ~ 14, 전주

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Background

Motivation Increase of IP service demands

# of hosts on the Internet has doubled per year # of web servers has doubled every 20 weeks From best efforts service to QoS guaranteed real-time multimedia services (-> ATM)

Information infrastructure based on ATM technology Needs for development of new services Needs for supporting legacy communication services (-> IP)

Communication evolution into wired/wireless integrated environment Rapid increase of mobile phone service users Needs for mobile multimedia services (-> Mobile ATM)

HSN ‘98‘98.2.12 ~ 14, 전주

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IP Mobility Support over ATM

MIP over ATM = MIP + IPOA Mobility support in IP layer Connectionless oriented mobility support

IP over WATM = IPOA + WATM Mobility support in ATM layer Connection oriented mobility support

HSN ‘98‘98.2.12 ~ 14, 전주

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Mobile IP

Internet RFCs RFC 2002 : IP Mobility Support RFC 2003 : IP Encapsulation within IP RFC 2004 : Minimal Encapsulation within IP RFC 2005 : Applicability Statement for IP Mobility Support RFC 2006 : The Definitions of Managed Objects for IP Mobility

HSN ‘98‘98.2.12 ~ 14, 전주

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Mobility Problems and Solutions

Mobility problems A name is a location-independent id An address reflects a host’s point of attachment to the network In IP, DNS(Domain Name System) is used for name-to-address

translation In MIP, the binding is a function of time

-> IP layer needs mobility control

Network layer solution architecture Two-tier addressing

Two internet addresses with each mobile host (Home address, Care-of address) - Home address for protocol processing - Care-of address for routing

HSN ‘98‘98.2.12 ~ 14, 전주

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MIP Components

R

R

Care-of address

Home address

CN

InternetHome network

Foreign network

MN

128. 8. 128

. . 2 . . 3

FA

HA

MN

HSN ‘98‘98.2.12 ~ 14, 전주

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Mobility Control

Advertisement

Registration Request

Registration Reply

Datagram

Tunneled datagram

MN

Decapsulation

Datagram

Encapsulation

FA HA

HSN ‘98‘98.2.12 ~ 14, 전주

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Routing Optimization

Home network

Foreign networkf

Cacheg

LD

MH

S

Source

Address translation agent

Location directory

HSN ‘98‘98.2.12 ~ 14, 전주

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IP vs. ATM

IP

Connectionless Currently No QoS Destination based routing Future, scalability Problem Moderate overhead

Mobile IP Variable packet size Multicast/broad cast

ATM

Connection Oriented QoS Support Fast Switching Scalable High overhead for IP over AT

M Wireless ATM Fixed packet size Yes but requires VC mesh or

MCS

HSN ‘98‘98.2.12 ~ 14, 전주

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IP over ATM

IPOA Paradigm

Layered Model

Classical IP over ATM

LAN Emulation(ATM Forum)

(IETF)

Multi-protocolover ATM

(ATM Forum)

Next Hop Resolution Protocol(IETF)

Integrated Model

I-PNNI(ATM Forum)

IP & TagSwitching (IETF)

HSN ‘98‘98.2.12 ~ 14, 전주

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Characteristics of Layered Model

IP overlays ATM with layer 3 (layered routing) ARP (IP, ATM) is required IP routing protocol in IP routers ATM routing protocols are used Modifications in ATM control SW are not required Inefficient multicasting Standardized Specs.

HSN ‘98‘98.2.12 ~ 14, 전주

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Characteristics of Integrated Model

Integrated routing protocol ARP (IP, ATM) is not required ATM routing protocols are not used Modifications in ATM control SW are required Efficient multicasting Standardized Specs. are in progress

HSN ‘98‘98.2.12 ~ 14, 전주

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Comparison : Route Selection

I-PNNII-PNNI

OSPFMPLS

PNNI

OSPFNHRP

Classic OSPF

PNNI PNNI PNNI

OSPF

IP

ATMIP

OSPF OSPF OSPF

OSPF OSPF OSPF OSPF

HSN ‘98‘98.2.12 ~ 14, 전주

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Comparison :Internode Communication Protocols

Type ofcommunication

MPLS NHRP I-PNNI

OSPFRouting OSPF/PNNI

I-PNNI

Signaling TDP,IFMP,...

PNNI I-PNNI

Address resolution

NHRP

HSN ‘98‘98.2.12 ~ 14, 전주

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IP over WATM (I)

IPaddr(= AP) --> (ATMvisiting_addr = AP)

i) IPaddr -- ARP -> ATMhome_addr -- MC(t) -> ATMvisiting_addr

ii) IPaddr ----- ARP*(t) -------> ATMvisiting_addr

HSN ‘98‘98.2.12 ~ 14, 전주

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IP over WATM (II)

IP Over WATM = IPOA + WATM

cf) MIP over ATM

NHRP

(X) MPLS

(X) I-PNNI

Mobility ControlMC(t)

Home agent

Foreign agent

NHRP

MPLS

I-PNNI

HSN ‘98‘98.2.12 ~ 14, 전주

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Location Management in WATM

LM enables the network to communicate with MN by managing the information about the location of the MN

LM = Mobile tracking + Mobile locating Mobile Tracking

Network elements updating procedure about the location of mobile entities

Mobile tracking = Mobile registration + updating

Mobile Locating The procedure by which a network node determines the

location of the MT for the delivery of incoming calls May be executed explicitly prior to call setup or may be an

integral part of the call setup procedure

HSN ‘98‘98.2.12 ~ 14, 전주

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Two Approaches for the LM in WATM

Mobile PNNI scheme LR scheme

HSN ‘98‘98.2.12 ~ 14, 전주

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Mobile PNNI Scheme

Extension of the PNNI routing protocol to support MN Use of the PNNI routing protocol for reachability information Scope parameter for the restriction of RI update

No explicit “search” procedure prior to call setup Connection setup combined with mobile locating

Requires additional routing optimization process

HSN ‘98‘98.2.12 ~ 14, 전주

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PNNI Routing Protocol Overview

Hierarchical peer groups with Peer Group Leaders(PGLs) and Logical Group Nodes(LGNs)

Exchange of information for topology, load and reachability by using Protocol Topology State Packet (PTSP)

Reachability summarized and advertised by PGLs

ATM switch

Peer group leaderl=1

l=2

l=L

A B

A.1 A.2B.1

B.2 B.3

A.1.1 A.1.2

A.1.3

A.1.4A.2.1

A.2.2 B.1.1 B.1.2

B.1.3

B.1.4B.1.5

B.2.3

B.2.1

B.2.2

B.3.1 B.3.2B.3.3

B.3.4

B.3.5B.3.6

HSN ‘98‘98.2.12 ~ 14, 전주

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PNNI Extension

Enhancement of the PNNI routing protocol for the exchange of reachability information of mobile users

Three new parameters are defined Scope S is used to set the stop point for reachability informatio

n propagation Ancestors-are-sibling level aij of nodes i and j is the level at whi

ch the ancestors of the two nodes i and j belong to the same peer group

The neighborhood Gi of a node i is defined to include all nodes j such that aij >= S

HSN ‘98‘98.2.12 ~ 14, 전주

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Mobile Tracking

Mobile registers at switch n

New location outsidethe neighborhood

of the old location ?ano < S

Send registrationto home swtich

Send registration to oldswitch to set a pointer at

to the old switch to forwardcalls to new location

Send registration to home switch ;Send registration to old switch

to set a pointer at the old switch to forward calls to new location

(if home = old, only one registration is needed)

Yes No

Power on/offregistration

Registrationresulting from a move from mode o to new node n

HSN ‘98‘98.2.12 ~ 14, 전주

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Connection Setup/Mobile Locating

Calls arrives at the origination switch

Call arrival wasafter reachability

update is complete

Call is routed directly to the mobile

Call is routed to the oldlocation and then

to the current locationof the mobile

Call arrival wasafter reachability

update is complete

Call is routed to the homeswitch and then

to the current locationof the mobile

Call is routed to the homeswitch, then to the old location

and finally to the currentlocation of the mobile

Call arrival wasafter home switch

receives registrationfollowing a move or the home is the

old location

Called mobileis in its home

neighborhood ?ahv >= S

Calling party is outside thecalled mobile’s neighborhood

acv < S

Calling party is within the

called mobile’s neighborhood

acv >= S

No

No

No

No

Yes

Yes

Yes

Yes

HSN ‘98‘98.2.12 ~ 14, 전주

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LR Scheme

Application of cellular LR scheme to PNNI-based hierarchical ATM networks Hierarchical LR DBs Scope parameter for the restriction of LR provisioning level

Isolate effect for mobility from PNNI routing protocol Explicit “search” procedure prior to call setup

HSN ‘98‘98.2.12 ~ 14, 전주

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LR Architecture

l=S=2

l=L

A.L B.L

A.1.L A.2.L B.1.L B.2.L B.3.L

A.1.1 A.1.2

A.1.3

A.1.4 A.2.1

A.2.2 B.1.1 B.1.2

B.1.3

B.1.4B.1.5

B.2.3

B.2.1

B.2.2

B.3.1 B.3.2 B.3.3

B.3.4

B.3.5B.3.6

BSBSA.1.2.5

A.1.1.4 A.1.2.3

B.2.2.5 ATM switch

LocationRegister

A.2.2.5

HSN ‘98‘98.2.12 ~ 14, 전주

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Mobile Tracking in the LR Scheme

Mobile registers at switch

Updates are propagatedfrom Lth level LR to

Sth level LR ; Home LR is informed about the current Sth level LR.

Updated are propagated from Lth level LR to

aonth level LR at the new

neighborhood ; Cancellations are propagated from

Lth level LR to aon + lth level LR at

the old neighborhood.

Updates are propagated from Lth level LR to

Sth level LR at the new neighborhood ; Home LR is informed about the new Sth

level LR ; Cancellations are propagated from Lth level

LR to Sth level LR at the old neighborhood.

aon >= S NoYes

Power on/offregistrationat switch n

Registrationresulting from amove from nodeo to new node n

HSN ‘98‘98.2.12 ~ 14, 전주

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Mobile Locating in the LR Scheme

Callingparty’s

switch(c)

Called mobile’s current switch(v)

Home switch of the called mobile(h)

l = I

l = S

l = L

LOCREQ

LOCREQ

LOCREQ

LOCREQ

LOCREQ

LOCREQ

LOCREQ

LOCREQResponse

HSN ‘98‘98.2.12 ~ 14, 전주

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Comparison

Item Mobile PNNI LR

Address space partition Not required Required

Resource allocation for call setup

Not optimized Optimized

Application to public network

Applicable Not applicable

Modification of ATM signaling and routing

Required Not required

Performance Superior in low CMR Superior in high CMR

HSN ‘98‘98.2.12 ~ 14, 전주

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Performance & Cost Issues

LM cost = Mobile tracking cost + Mobile location cost Mobile tracking (locating) cost

= Computational cost (DB access)

+ Communication cost (signaling & routing) For performance analysis, exact models of network and mobile no

de are required