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Name Service in IPv6 Mobile Ad-hoc Network connected to the Internet

Jaehoon Jeong, ETRIpaul@etri.re.kr

http://www.adhoc.6ants.net/~paul/

PIMRC 2003

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Contents Introduction Related Work Name Service within IPv6 MANET

Ad-hoc Name Service System (ANS) Name Service for the Internet Procedure of DNS Name Resolution Conclusion

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Introduction

Name Service in Mobile Ad-hoc Network(MANET) MANET has dynamic network topology

Current DNS can not be adopted in MANET! Because it needs a fixed and well-known name server

Idea of Name Service in MANET All the mobile nodes take part in name service

Every mobile node administers its own name information It responds to the other node’s DNS query related to its

domain name and IP address

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Related Work (1/2): Link-Local Multicast Name Resolution (LLMNR)

DNS service based on IP multicast in link-local scoped network IETF DNSEXT working group item

Each node performs the role of DNS name server for its own domain name.

LLMNR Sender LLMNR Responder

LLMNR query message (What is IPv6 address of “host.private.local.”?) - It is sent in link-local multicast

LLMNR response message (IPv6 address of “host.private.local.”) - It is sent in link-local unicast

Verification of LLMNR response - Does the value of the response conform to the addressing requirements? - Is hop-limit of IPv6 header 1?

If the result is valid, then the Sender caches and passes the response to the application that initiated DNS query.

else the Sender ignores the response and continues to wait for other responses.

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Related Work (2/2): Autoconfiguration Technology IP Interface Configuration Name Service

Translation between host name and IP address Generation of unique domain name

IP Multicast Address Allocation Service Discovery

Unicast Service Multicast Service

AutoconfigurationTechnology

IP Interface Configuration

Nam

e S

erv

ice

Ser

vic

e D

isc

ov

ery

IP Multicast Address Allocation

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Ad-hoc Name Service Systemfor IPv6 MANET (ANS)

ANS provides Name Service in MANET MANET DNS Domain

ADHOC.

MANET IPv6 Prefix IPv6 Site-local Prefix

FEC0:0:0:0::/64

Architecture of ANS System ANS Responder

It performs the role of DNS Name Server

ANS Resolver It performs the role of DNS Resolver

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ANS System (1/2)

ANSResolver

ApplicationApplication

Process

Database

Node

Mobile Node A

UNIX Datagram Socket

ANSResponder

ANSZone DB

Memory Read / Write

ANSResolver

ApplicationApplication

Mobile Node B

ANSResponder

ANSZone DB

Wireless Link

ANSResolver

ApplicationApplication

ANSResponder

ANSZone DB

ANSResolver

ApplicationApplication

ANSResponder

ANSZone DB

Mobile Node C

ANSResponder

ANSResolver

ApplicationApplicationApplicationApplicationANS

Zone DB

DNS Query

DNS Response

DNS Message

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ANS System (2/2)

Main-Thread

DUR-Thread

ANSZone DB

ANS Responder

Process

Thread

Database

Memeory Read / Write

Internal Connection

Main-Thread

Resolv-ThreadTimer-Thread

ANS Cache

ANS Resolver

Process

Thread

Cache

UNIX Datagram Socket

Memeory Read / Write

Internal Connection

Application

ANS API

DNS Query

DNSResponse

DNS Query / DNS Response

UDP Socket Connection

UDP Socket Connection

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Name Service in ANS Name Generation

generates a unique domain name based on the network device identifier

Zone File Generation generates ANS zone file with the unique domain name

and corresponding IPv6 address

Name Resolution performs the name-to-address translation

Service Discovery performs the service discovery through DNS SRV

resource record, which indicates the location of server or

the multicast address of the service

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Scenario of Name Service within MANET

MN-A MN-B MN-C

DNS Query Message(MN-C.ADHOC.)

DNS Query Messageis sent in Multicast Receipt of

DNS Query Message

Request ofHost DNS Name

Resolution

Receipt and Processof DNS Query Message

DNS Response Message(MN-C’s IPv6 Address)

Gain ofDNS Information

MN-A tries to connect to the server on MN-C

The server on MN-C acceptsthe request of the connection

from MN-A

DNS Query Message(MN-C.ADHOC.)

DNS Response Messageis sent in Unicast

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Name Service for the Internet

When a MANET Node communicates with an Internet Node, MANET Node should find out Internet Gateway(s). MANET Node should resolve the Internet Node’s

DNS name into its globally routable IPv6 address.

Discovery of Internet Gateway RS/RA-based Discovery

Discovery of Global DNS Server Recursive DNS Server (RDNSS) Option within RA

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Discovery of Internet Gateway (IGW) & Recursive DNS Server (RDNSS)

Internet

RDNSS3

DNS Server(DNSS)

MANET2MANET1

Internet Gateway1(IGW1)

RDNSS1

RS

MN1MN2 MN3

Web Server(WS)

Internet Gateway2(IGW2)

RDNSS2

RA

RA Header

Prefix Information Option: IGW2’s Global IPv6 Prefix

RDNSS Option: RDNSS3’s MANET Address

RA Message from IGW2

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Procedure of DNS Name Resolution

Input a DNS name

Does the DNS name belong to

Ad-hoc domain?

Resolve the DNS namethrough ANS Resolver

YES

Resolve the DNS namethrough DNS Resolver

NO

Output IPv6 address(es)corresponding to the DNS name

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Conclusion ANS (Ad-hoc Name Service System for IPv6 MANET)

A new name service scheme in IPv6 MANET connected to the Internet.

Name Service of ANS Automatic name generation Automatic zone file generation Name-to-address translation

Name Resolution of MANET Node Name Resolution of Internet Node

Service discovery

Future Work We will enhance ANS to provide secure name service.

Authentication of DNS response message through Pre-shared group key and IPsec ESP’s null-transform

or through Pre-shared group key and DNS TSIG (RFC2845)

TSIG : Secret Key Transaction Authentication for DNS