Broadband Forum Focus: IPv6 Home Network

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Broadband ForumFocus IPv6 Home Network

• David Milesdavid.miles_at_alcatel-lucent.com

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The views in this presentation do notrepresent
the opinion of the Broadband Forumor its
members. All document are Work In Progress.
Disclaimer
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What is theBroadband Forum?
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The Broadband Forum Vision Develop the full
potential of broadband around the world.
Mission The Broadband Forum is a worldwide
organization committed to rapidly creating
specifications for communication service
providers and vendors that - Accelerate the
development and deployment of broadband networks,
Foster successful interoperability, Manage and
deliver advanced IP services to the customer.
http//www.broadband-forum.org/about/mission.php
Forum History The Broadband Forum is a global
consortium of nearly 200 leading industry players
covering telecommunications, equipment,
computing, networking and service provider
companies. Established in 1994, originally as
the ADSL Forum and later the DSL Forum, the
Broadband Forum continues its drive for a global
mass market for broadband, to deliver the
benefits of this technology to end users around
the world over existing copper telephone wire
infrastructures.
http//www.broadband-forum.org/about/forumhistory.
php
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IPv6 for Consumer Deployment Options
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Native IPv6
IPv6HomeNetwork
IPv6Internet
IPv6Gateway
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Softwires from Client in the Home Network
IPv6HomeNetwork
IPv4Internet
IPv6Internet
L2TP Tunnel
DSL Router(Existing)
Softwire Client
SoftwireConcentrator
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Native IPv6 using L2TP
IPv6HomeNetwork
IPv6Internet
L2TP
PPPoA
IPv6Gateway
LAC
IPv6 LNS
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Host Access using PPPoE
IPv6Internet
L2TP
PPPoE
Bridge
LAC
IPv6 LNS
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Host Access using Softwires
IPv4Internet
IPv6Internet
L2TP Tunnel
PPPoE
IPv4 Router
SoftwireConcentrator
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IPv6 for ConsumerBroadband WT-177 and WT-187
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Routing Home Network
Internet
Subnet A
Subnet B
NAT Function
TCP
UDP
UDP
TCP
IPoE IWF
IPv4
IPv4
IPv4
IPv4
802.1ad
Ethernet
802.1ad
Ethernet
Ethernet
Ethernet
Ethernet
RFC 2684
ATM
802.3 PHY
802.3 PHY
DSL
Routing
IPoE IWF
IPv6
IPv6
IPv6
802.1ad
Ethernet
802.1ad
Ethernet
Ethernet
Ethernet
Ethernet
RFC 2684
ATM
802.3 PHY
802.3 PHY
DSL
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Routed Gateway with PPPoE WAN (1)
Subnet A
Subnet B
Routed Gateway
BNG
RADIUS
PPPoEPADI PADO PADR - PADS
PPP LCP ConfReqConfReq MRU, Magic Number
PPP LCP ConfReqConfReq MRU, Magic Number,
AuthPAP
PPP LCP ConfAckConfReq MRU, Magic Number,
AuthPAP
PPP LCP ConfAckConfReq MRU, Magic Number
PAP Authenticate-RequestUsername (Peer-ID)
Password
RADIUS Access-RequestUser-Name, Password,
Service-Name VSAService-TypeFramed,
Framed-ProtocolPPP
RADIUS Access-AcceptDelegated-IPv6-Prefix,
IPv6-DNS, (IPv6-Address/Framed-IPv6-Pool)
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Routed Gateway with PPPoE WAN (2)
Subnet A
Subnet B
Routed Gateway
BNG
RADIUS
PAP Authenticate-Ack
PPPPhase
IPv6CP ConfReqInterface-Id 64-bit Interface
ID/Client
IPv6CP ConfAck Interface-Id 64-bit Interface
ID/Client
IPv6CP ConfReq Interface-Id 64-bit Interface
ID/BNG
IPv6CP ConfAckInterface-Id 64-bit Interface
ID/Client
RADIUS Accounting-RequestStart, User-Name,
Service-Name VSAService-TypeFramed,
Framed-ProtocolPPP
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Routed Gateway with PPPoE WAN (3)
Subnet A
Subnet B
Routed Gateway
BNG
RADIUS
Multicast Router AdvertisementNumbered M1,O0,
No PIOUn-numbered M0, O1, No PIO
DHCPv6 SOLICITIA_PD-Option, (IA_NA-Option),
DNS-Servers Option
DHCPv6Phase
DHCPv6 ADVERTISEIA_PD-Option Prefix, (IA_NA)
DHCPv6 REQUESTIA_PD-Option, (IA_NA-Option),
DNS-Servers Option
DHCPv6 REPLYIA_PD-Option Prefix, (IA_NA)
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Routed Gateway with Ethernet WAN (1)
Subnet A
Subnet B
Routed Gateway
BNG
RADIUS
Multicast Router AdvertisementNumbered M1,O0,
No PIOUn-numbered M0, O1, No PIO
DHCPv6 SOLICITIA_PD-Option, (IA_NA-Option),
DNS-Servers Option
DHCPv6Phase
RADIUS Access-RequestUser-Name, Password,
Service-Name VSAService-TypeFramed
RADIUS Access-AcceptDelegated-IPv6-Prefix,
IPv6-DNS, (IPv6-Address/Framed-IPv6-Pool)
DHCPv6 ADVERTISEIA_PD-Option Prefix, (IA_NA)
DHCPv6 REQUESTIA_PD-Option, (IA_NA-Option),
DNS-Servers Option
DHCPv6 REPLYIA_PD-Option Prefix, (IA_NA)
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Bridged Home with PPPoE Host
Internet
IPv4
PPPoE
Bridge
IPv4
802.1ad
Ethernet
802.1ad
Ethernet
Ethernet
Ethernet
RFC 2684
ATM
802.3 PHY
802.3 PHY
DSL
IPv6
PPPoE
Bridge
IPv6
802.1ad
Ethernet
802.1ad
Ethernet
Ethernet
Ethernet
RFC 2684
ATM
802.3 PHY
802.3 PHY
DSL
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Bridged Home with PPPoE Host (1)
Bridge
BNG
RADIUS
PPPoEClient
PPPoEPADI PADO PADR - PADS
PPP LCP ConfReqConfReq MRU, Magic Number
PPP LCP ConfReqConfReq MRU, Magic Number,
AuthPAP
PPP LCP ConfAckConfReq MRU, Magic Number,
AuthPAP
PPP LCP ConfAckConfReq MRU, Magic Number
PAP Authenticate-RequestUsername (Peer-ID)
Password
RADIUS Access-RequestUser-Name, Password,
Service-Name VSAService-TypeFramed,
Framed-ProtocolPPP
RADIUS Access-AcceptIPv6-DNS, Framed-IPv6-Prefix
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Bridged Home with PPPoE Host (2)
Bridge
BNG
RADIUS
PPPoEClient
PPPPhase
PAP Authenticate-Ack
IPv6CP ConfReqInterface-Id 64-bit Interface
ID/Client
IPv6CP ConfAck Interface-Id 64-bit Interface
ID/Client
IPv6CP ConfReq Interface-Id 64-bit Interface
ID/BNG
IPv6CP ConfAckInterface-Id 64-bit Interface
ID/Client
RADIUS Accounting-RequestStart, User-Name,
Service-Name VSAService-TypeFramed,
Framed-ProtocolPPP
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Bridged Home with PPPoE Host (3)
Bridge
BNG
RADIUS
PPPoEClient
Anti-SpoofingInstalled
Multicast Router AdvertisementM0, O1Prefix
Information Option from Framed-IPv6-Prefix
OptionalDHCPv6StatelessPhase
DHCPv6 INFORMATION-REQUESTDNS-Servers Option
DHCPv6 REPLYDNS-Servers Option
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Prefix Size Broadband Subscribers
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IPv4 and IPv6 Routing Gateways
Internet
NAT Function
TCP
UDP
UDP
TCP
IPoE IWF
IPv4
IPv4
IPv4
IPv4
802.1ad
Ethernet
802.1ad
Ethernet
Ethernet
Ethernet
Ethernet
RFC 2684
ATM
802.3 PHY
802.3 PHY
DSL
Routing
IPoE IWF
IPv6
IPv6
IPv6
802.1ad
Ethernet
802.1ad
Ethernet
Ethernet
Ethernet
Ethernet
RFC 2684
ATM
802.3 PHY
802.3 PHY
DSL
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IPv4 and IPv6 Routing Gateways
Internet
NAT Function
Network Address TranslationCustomer-selected
addresses on LAN
TCP
UDP
UDP
TCP
IPoE IWF
IPv4
IPv4
IPv4
IPv4
802.1ad
Ethernet
802.1ad
Ethernet
Ethernet
Ethernet
Ethernet
RFC 2684
ATM
802.3 PHY
802.3 PHY
DSL
IPv6 RoutedProvider-assigned addresses on the LAN
Routing
IPoE IWF
IPv6
IPv6
IPv6
802.1ad
Ethernet
802.1ad
Ethernet
Ethernet
Ethernet
Ethernet
RFC 2684
ATM
802.3 PHY
802.3 PHY
DSL
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IPv6 Prefix Delegation

• Allows the routing gateway to receive a range of
  IPv6 addresses (a prefix) that are valid for that
  subscriber. The gateway must manage the
  assignment of individual addresses to hosts
  outside the scope of Prefix Delegation.

BNG
RoutingGateway
DHCPv6 SolicitIA_PD Option
DHCPv6 AdvertiseIA_PD Prefix Option ltprefixgt
DHCPv6 Request IA_PD Prefix Option ltprefixgt
DHCPv6 ReplyIA_PD Prefix Option ltprefixgt
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Contents of the Prefix Delegation Option
0
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Option IA_PD
option-length
IAID
Timer 1
Timer 2
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Contents of the Prefix Delegation Option
0
16
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Option IA_PD
option-length
IAID
Contact the delegating router at this time to
extend
Contact _any_ delegating router at this time to
extend
Option IAPREFIX
option-length
Preferred Lifetime of addresses derived from this
prefix
Valid Lifetime of addresses derived from this
prefix
prefix-length
IPv6 Prefix
IPv6 Prefix
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How Small?

• If Stateless Address Auto-Configuration (SLAAC)
  is to be supported, the prefix-length of any IPv6
  link must be exactly 64-bits
• /64
• RFC 4862If the sum of the prefix length in
  the PIO and the interface identifier length is
  not equal to 128 bits, the Prefix Information
  option MUST be ignored
• RFC 2464 IPv6 over EthernetThe Interface
  Identifier is 64-bits and is based on the EUI-64
  format.

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How Big?
Single Subnet
Internet
Subnet A
Two Subnets
Internet
Subnet A
Subnet B
Cascading Routers
Internet
Subnet A
Subnet C
Subnet B
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The views

• http//www.apnic.net/policy/ipv6-guidelines.html
• An LIR can assign a /64 to /48 to an end site
  customer network based on their requirements. The
  following guidelines may be useful
• /64 where it is known that only one subnet is
  required.
• /56 for small sites where it is expected only a
  few subnets will be required within the next two
  years. Subscribers can receive a /56 when
  connecting through on-demand or always-on
  connections such as small office and home office
  enterprises.
• /48 for larger sites, or if an end site is
  expected to grow into a large network.
• An LIR must submit a second opinion request to
  APNIC if it plans to assign more than a /48 to a
  single end site
• Assignments for networks equal to or greater than
  /48 must be registered.

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What is the impact?

• Using a prefix longer than a /56 does not
  affect your allocation. HD-Ratio is calculated
  against /56 prefixes.
• The use of a shorter prefix does not increase the
  number of routes or FIB entries in Service
  Provider infrastructure.
• In the minimum /32 LIR allocation, there are
• 16,777,216 /56
• 6,183,533 /56 at HD-Ratio 0.94

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How many subnets is enough?

• With cascading routers we must support at least
  two subnets.
• The closest nibble is a /60, with 16 subnets.
• WT-187 and WT-177 Requirement
• R-xx A minimum delegation of a /60 to a
  Routing Gateway.
• R-xx A recommended delegation of a /56 to a
  Routing Gateway.

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IPv6 Addressing Importance of Persistent Addresses
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Impact of Valid Preferred Lifetimes
00000
Host links can come up before the broadband
connection.
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Impact of Valid Preferred Lifetimes
00100
DHCPv6 Prefix Delegation T1 30 min T2 48
min IA_PD 2001db81/64Preferred 3600
Valid 43200
Router Advertisement PIO 2001db81/64Preferre
d 3600 Valid 43200Autonomous, On-Link
DHCPv6-PD options used in Router Advertisements.
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Impact of Valid Preferred Lifetimes
00130
Lifetimes are tracked by the Host and decremented.
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Impact of Valid Preferred Lifetimes
00135
Router Advertisement PIO 2001db81/64Preferre
d 3565 Valid 43165Autonomous, On-Link
And the RG also tracks lifetimes so that any
RAare accurate.
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Impact of Valid Preferred Lifetimes
00140
Router AdvertisementROUTER LIFETIME 0 PIO
2001db81/64Preferred 3560 Valid
43160Autonomous, On-Link
If the Broadband Link goes down, set Router
Lifetimeto zero (0) so that the RG is not used
as default router.
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Impact of Valid Preferred Lifetimes
00240
Router AdvertisementROUTER LIFETIME 0 PIO
2001db81/64Preferred 3500 Valid
43100Autonomous, On-Link
Prefixes are still valid even when link is
down.RA continue to be sent.
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Impact of Valid Preferred Lifetimes
10240
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Impact of Valid Preferred Lifetimes
10500
DHCPv6 Prefix Delegation T1 30 min T2 48
min IA_PD 2001db81/64Preferred 3600
Valid 43200
Router Advertisement PIO 2001db81/64Preferre
d 3600 Valid 43200Autonomous, On-Link
Whenever DHCPv6-PD provides the RG new
lifetimesthese are reflected in the RA
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Impact of Changing Prefixes
10600
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Impact of Changing Prefixes
10700
DHCPv6 Prefix Delegation T1 30 min T2 48
min IA_PD 2001db82/64Preferred 3600
Valid 43200
Router Advertisement PIO 2001db82/64Preferre
d 3600 Valid 43200Autonomous, On-Link
Source Address Selection is NOT deterministic,
however theBroadband Network Gateway is only
expecting trafficsourced from 2001db82/64
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Better Behaviour
10700
DHCPv6 Prefix Delegation T1 30 min T2 48
min IA_PD 2001db82/64Preferred 3600
Valid 43200
On-Link
Router Advertisement PIO 2001db81/64PREFERRE
D 0 Valid 43080Autonomous, On-Link PIO
2001db82/64Preferred 3600 Valid
43200Autonomous, On-Link
Instead, let us Deprecate the old addresses. We
cannot invalidate because of DoS-protection rules.
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Better Behaviour
10730
Router Advertisement PIO 2001db82/64Preferre
d 3540 Valid 43140Autonomous, On-Link
Source Address Selection will now prefer the new
address space.
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IPv6 Addressing Minimising Prefix Changes
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Address Hierarchy _at_ BNG Day 2
Route table--------------------------------------
----------------------2001db8/39 aggregate lo
02001db800/56 subscriber eth12001db8010
0/56 subscriber eth1...
2001db800/56
2001db80100/56
2001db80200/56
2001db80300/56
2001d8b/39
2001db80400/56
Route table--------------------------------------
----------------------2001db8200/39 aggregate
lo02001db82000/56 subscriber eth12001db8
200100/56 subscriber eth1...
2001db80500/56
2001db82000/56
2001db8200100/56
2001db8200200/56
2001d8b200/39
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Address Hierarchy _at_ DSLAM Day 1
2001db800/56
Route table--------------------------------------
----------------------2001db8/46 aggregate lo
02001db84/46 aggregate lo02001db88/46 ag
gregate lo02001db800/56 subscriber eth120
01db80100/56 subscriber eth1...
2001db80100/56
2001db80200/56
2001d8b/46
2001db840/56
2001db84100/56
2001db84200/56
2001d8b4/46
2001db880/56
2001db88100/56
2001db88200/56
2001d8b8/46
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Address Hierarchy _at_ DSLAM Day 2
Route table--------------------------------------
----------------------2001db8/46 aggregate lo
02001db84/46 aggregate lo02001db800/56
subscriber eth12001db80100/56 subscriber et
h1...
2001db800/56
2001db80100/56
2001db80200/56
2001d8b/46
2001db840/56
2001db84100/56
Route table--------------------------------------
----------------------2001db88/46 aggregate lo
02001db880/56 subscriber eth12001db8810
0/56 subscriber eth1...
2001db84200/56
2001d8b4/46
2001db880/56
2001db88100/56
2001db88200/56
2001d8b8/46
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Address Hierarchy

• Prefix Delegation
• The BNG should aggregate subscriber /56 prefixes
  into supernets within the service provider
  domain. The aim is to reduce the size of the
  service provider routing table.
• Logically group prefixes by the largest logical
  device (switch, DSLAM, etc) that is persistent
  regardless of normal network rearrangement.

Recommend Each access node should be represented
by its own unique prefix-pool when DHCPv6 PD is
in use
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Thank You
www.alcatel-lucent.com