230-6deploy_IPv6_and_DSL_20120207_v2_0

7/27/2019 230-6deploy_IPv6_and_DSL_20120207_v2_0

1/16

IPv6 and xDSL

Speaker name


2/16

Copy ... Rights

This slide set is the ownership of the 6DEPLOY project via its

partners

The Powerpoint version of this material may be reused andmodified only with written authorization

Using part of this material must mention 6DEPLOY courtesy

es are ava a e rom www. ep oy.org

Looking for a contact ? Mail to : [email protected]


3/16

Outline

Entities in an xDSL Environment

PPP over AAL5 (PPPoA) PTA

over o PPP over Ethernet (PPPoE)

IPv6 and Radius

IPv6 and Radius Attributes


4/16

Entities in an xDSL Environment

Subscriber (xDSL User)

, ,

Network Access Provider (NAP)

.

DSLAM, BBRAS, radius server*


5/16

Entities in an xDSL Environment (#2)

Network Service Provider

.

May offer other added-value services.

Edge router, radius server


6/16

Implementation Details

xDSL modem

,

(de)modulation

DSL Access Multi lexer DSLAM

Signal (de)modulation, aggregates traffic over ATM links

Broad Band Remote Access Concentrator BBRAS

Terminates the Subscribers ATM connections, tunnels or

routes traffic to the NSP edge router.


7/16

Implementation Details

Radius Server

NSP edge router

,

Internet


8/16

Ethernet Bridging over ATM

The CPE forwards IP packets using multi-protocol encapsulation over

ATM adaptation layer 5 (AAL5).

Minimum functionality is required for CPE, aka xDSL modem (L3

unaware device).

Subscribers PCs are configured with static IPv6 address, or via

DHCPv6 or via auto-configuration

This method does not support authentication and authorization

functionality!


9/16

PPP over AAL5 (PPPoA) - PTA

The CPE supports IPv6/4 packet forwarding and interconnects multiple

systems in the Subscribers local network.

CPE router to establish two PPP sessions; an IPv6 (IPCPv6) and an

IPv4 (IPCPv6).

attributes stored in a centralised radius server or local database.

The CPE can be authenticated using one of the multiple protocols, such

, , - , , .


10/16

PPP over AAL5 (PPPoA) - LAA

In case theNAP and theNSP are different, the PPP sessions do not

terminate at theBBRAS but at the edge router.

BBRAS =L2TP Access Concentrator (LAC)

Edge router =L2TP Network Server (LNS)

Two PPP sessions are established from the CPE router which terminate

at theLNS.LAC is IPv6-unaware. Address assignment and authentications methods are performed in the

NSP.


11/16

PPP over Ethernet (PPPoE)

Separate PPP sessions are established between the Subscribers

systems (or CPE) and the BBRAS for IPv6 and IPv4 traffic.

Sessions may terminate in the LNS in the NSP network (not shown).

If PPP sessions terminate at theSubscribers system, then the CPE may be

, . , ,

installed in theSubscribers systems. The advantage of this approach is thatallows access control and service selection to be done on per-subscriber

rather than on per-site basis.


12/16

IPv6 and Radius

Radius protocol Provides authentication, authorisation and

accounting services

Necessary in any xDSL deployments, e.g.stores large number of user information

instead of keeping them in the LNS

address allocation, ACLs


13/16

IPv6 and Radius

Radius message exchange The IPv6 attributes may be sent along with IPv4-

related attributes within the same RADIUS

attributes to use

-

not know a-priori whether the host will be using

IPv4, IPv6, or both. For example, within PPP,IPv6CP occurs after LCP, so that address

assignment will not occur until after RADIUS

au en ca on an au or za on as comp e e .


14/16

IPv6 and Radius Attributes (RFC3162)

NAS-IPv6-Address: Indicates the identifying IPv6

authentication of the user. NASIPv6-Address is only

used inAccess-Request packets

Framed-Interface-Id: Specifies the IPv6 interface IDto be assigned to a user

Framed-IPv6-Prefix: Specifies the IPv6 networks to

be assigned to a user.


15/16

IPv6 and Radius Attributes (RFC3162) #2

Framed-IPv6-Route: Specifies the IPv6 routing

Framed-IPv6-Pool: Specifies the name of a RAS

mana ed ool from which the RAS should assi n an

IPv6 prefix Lo in-IPv6-Host: Indicates the s stem with which to

connect the user, when the Login-Service Attribute is

included.


16/16

IPv6 configuration in End User

Microsoft Windows XP or earlier version: PPPv6 not

supported

n ows s a: m e e suppor , w ou userconfiguration

ac

Linux FreeBSDpppd, dhcp6 (WIDE Kame project), rtadvd

Documents

230-6deploy_IPv6_and_DSL_20120207_v2_0