RFC 5549 - RIPE 65 RFC 5549 BGP IPv4 NLRIs with an IPv6 next hop RIPE-65 Amsterdam 25-09-2012...

download RFC 5549 - RIPE 65 RFC 5549 BGP IPv4 NLRIs with an IPv6 next hop RIPE-65 Amsterdam 25-09-2012 arien.vijn@ams-ix.net

If you can't read please download the document

  • date post

    07-Jun-2020
  • Category

    Documents

  • view

    0
  • download

    0

Embed Size (px)

Transcript of RFC 5549 - RIPE 65 RFC 5549 BGP IPv4 NLRIs with an IPv6 next hop RIPE-65 Amsterdam 25-09-2012...

  • RFC 5549 BGP IPv4 NLRIs with an IPv6 next hop

    RIPE-65 Amsterdam 25-09-2012 arien.vijn@ams-ix.net

    stefan.plug@ams-ix.net

  • Overview

    • No more IPv4! • Possible solutions • RFC 5549

    2RIPE 65 Amsterdam 25-09-2012

  • No more IPv4!

    • AMS-IX Internet peering VLAN: • 1024 IPv4 (/22) •

    18,446,744,073,709,551,616 IPv6 (/64)

    3RIPE 65 Amsterdam 25-09-2012

  • No more IPv4!

    IPv4 usage 2006-2012 Latest data: 11-sept-2012

    – Used: 657

    – Left: 367

    4RIPE 65 Amsterdam 25-09-2012

    01-01-2006 01-01-2008 01-01-2010 01-01-2012 0

    100

    200

    300

    400

    500

    600

    700

    800

    Used IPv4 Left IPv4

  • No more IPv4!

    Growth of IPv4 usage Latest data: 11-sept-2012

    • 56, but we still have 4 months to go..

    Probable reason: AMS-IX reseller program

    5RIPE 65 Amsterdam 25-09-2012

    2006 2007 2008 2009 2010 2011 2012 0

    10

    20

    30

    40

    50

    60

    70

    80

    90

    Predicted Growth

  • No more IPv4!

    Predicted growth of IPv4 usage – Worst case: 100 each year, depletion 2016

    – Best case: 75 each year, depletion in 2017

    6RIPE 65 Amsterdam 25-09-2012

    01-01-2006 01-01-2008 01-01-2010 01-01-2012 01-01-2014 01-01-2016 01-01-2018 0

    200

    400

    600

    800

    1000

    1200

    1400

    Recorded IPv4 usage Predicted IPv4 usage 100 Predicted IPv4 usage 75 1024

  • Overview

    • No more IPv4! • Possible solutions • RFC 5549

    7RIPE 65 Amsterdam 25-09-2012

  • Possible solutions

    #1: Bigger subnet (/21) ● Because IPv4 address space is unlimited!... Oh wait... ● Could give us +-10 more years ● Bigger IPv4 broadcast domain == more ARP problems ● Not a solution, just a workaround

    8RIPE 65 Amsterdam 25-09-2012

  • Possible solutions

    #2: Private address space ● No member (500+) could use that private range anymore ● Including management interfaces ● ACLs deny private range traffic

    9RIPE 65 Amsterdam 25-09-2012

  • Possible solutions

    #3: Advertising IPv4 next-hops Could we use an IPv6 address as a next hop for its IPv4 routes?

    10RIPE 65 Amsterdam 25-09-2012

  • Possible solutions

    #3.1: 4in6 tunnel ● With what IPv4 addresses as termination points? ● Wouldn't solve our problem

    11RIPE 65 Amsterdam 25-09-2012

  • Possible solutions

    #3.2: '4in6' Softwire mesh tunnel [RFC 5565] ●Tunnel terminates in the router itself ●Encapsulate every IPv4 packet (+40B per packet) ●Non-IPv4 members can participate in IPv4 routing

    12RIPE 65 Amsterdam 25-09-2012

  • Possible solutions

    #3.3: Just send out the IPv4 packet ●We actually only need a L2 address for the next hop ●No need for encapsulation == no overhead ●But what if the next hop is not dual stack?

    13RIPE 65 Amsterdam 25-09-2012

  • RFC 5549

    14RIPE 65 Amsterdam 25-09-2012

    • No more IPv4! • Possible solutions • RFC 5549

  • RFC 5549

    15RIPE 65 Amsterdam 25-09-2012

  • RFC 5549

    *Receive an MP_BGP update message* *Look at the MP_REACH_NLRI attribute*

    IF ((Update AFI == IPv4)

    &&

    (Length of next hop == 16 Bytes || 32 Bytes))

    {

    This is an IPv4 route with an IPv6 next hop;

    }

    16RIPE 65 Amsterdam 25-09-2012

  • RFC 5549

    Example MP_REACH_NLRI attribute: ●AFI: = 1 (IPv4) ●SAFI: = 1 (unicast) ●Next hop length = 32 ●Next hop address = 2001::2 & FE80::1 ●NLRI = 192.0.2.0/24

    17RIPE 65 Amsterdam 25-09-2012

  • RFC 5549

    18RIPE 65 Amsterdam 25-09-2012

  • RFC 5549

    BGP capability advertisement Used to signal BGP capabilities between peers in OPEN message

    Capability code: 5 Extended Next Hop Encoding

    NLRI AFI: 1 IPv4

    NLRI SAFI: 1 Unicast

    Nexthop AFI: 2 IPv6

    19RIPE 65 Amsterdam 25-09-2012

  • RFC 5549

    20RIPE 65 Amsterdam 25-09-2012

  • RFC 5549

    Possible NLRI AFI/SAFI combinations AFI= IPv4 (1)

    SAFI ● Unicast (1) ● Multicast (2) ● Include an MPLS Label (4) ● MPLS-labeled VPN address (128)

    Next hop = IPv6

    21RIPE 65 Amsterdam 25-09-2012

  • RFC 5549

    Pros: ●IXPs wouldn't need IPv4 anymore ●No more ARP flooding

    Cons: ●Forwarding might be complicated ●No real implementations yet (as fas as we know) ●Members need to implement this, not AMS-IX

    22RIPE 65 Amsterdam 25-09-2012

  • Questions/comments/brilliant solutions: arien.vijn@ams-ix.net

    stefan.plug@ams-ix.net

    Dia 1 Dia 2 Dia 3 Dia 4 Dia 5 Dia 6 Dia 7 Dia 8 Dia 9 Dia 10 Dia 11 Dia 12 Dia 13 Dia 14 Dia 15 Dia 16 Dia 17 Dia 18 Dia 19 Dia 20 Dia 21 Dia 22 Dia 23