1 Proxy-ARP/ND in EVPN IETF92 – March 2015 draft-snr-bess-evpn-proxy-arp-nd-00 Jorge Rabadan (ALU) Senthil Sathappan (ALU) Kiran Nagaraj (ALU) Wim Henderickx (ALU) Thomas King (DE-CIX) Daniel Melzer (DE-CIX) Proxy-ARP/ND in EVPN networks IETF 92, March 2015 Dallas, USA draft-snr-bess-evpn-na-flags-01 Jorge Rabadan (ALU) Senthil Sathappan (ALU) Kiran Nagaraj (ALU)

2 Proxy-ARP/ND in EVPN IETF92 – March 2015 RFC7432 (EVPN) section 10: “the PE SHOULD perform ARP proxy” but it does NOT indicate HOW. There are other documents explaining proxy-ARP/ND functions but they are not specific to EVPN networks and do NOT solve the REQUIREMENTS for certain use- cases (e.g. IXP networks). Solution requirements: ­ Flexible LEARNING of proxy-ARP/ND entries ­ FLOODING suppression/reduction of ARP/ND messages ­ Network TRANSPARENCY ­ Efficient MAINTENANCE of the entries to avoid unnecessary control plane overhead ­ DUPLICATE IP detection and optional protection Why a Proxy-ARP/ND draft for EVPN networks?

3 Proxy-ARP/ND in EVPN IETF92 – March 2015 The Proxy-ARP/ND concept in EVPN PE2 PE1 PE3 MAC- VRF1 MAC1/IP1 Proxy-ARP MAC/IPtype MAC1-IP1EVPN MAC2-IP2EVPN MAC4-IP4dynamic MAC3-IP3static MAC1/IP1 MAC1/IP1 ARP/GARP MAC4/IP4 MAC1/IP1 snooped MAC4/IP4 snooped MAC4/IP4 MAC4/IP4 ARP/GARP PE3 MAC-VRF1MAC-VRF1 Who has IP1? MAC1 has IP1 MAC- VRF1 MAC2/IP2 As PE3 learns more and more IP->MAC entries it will progressively reduce the ARP/ND flooding to the remote PEs When PE3 knows all the hosts in the EVI it will no longer flood ARP/ND/unknown unicast (IXP use-case)

4 Proxy-ARP/ND in EVPN IETF92 – March 2015 EVPN Proxy-ARP/ND sub-functions IP->MAC entries: -Static -Dynamic (Snoop ARP/NA) -EVPN Precedence When a PE should or should not reply Age-time Send-refresh Admin choices to suppress: -Unknown ARP-Request/NS -Unsolicited GARPs/Nas And how to use them Monitors IP-moves (different MACs) Detection: N-moves in M-secs Assisted by a CONFIRM message Action: alarm and optionally ‘anti- spoofing-mac’, for HOLD-DOWN-secs

5 Proxy-ARP/ND in EVPN IETF92 – March 2015 MAC2/IPv6-2 R=0 snooped MAC1/IPv6-1 R=1 snooped Proxy-ND and NA R-bit flag draft-snr-bess-evpn-na-flags-01 PE2 PE1 PE3 MAC- VRF1 MAC1/IPv6-1 Ext-com R=1 Proxy-ND MAC/IPv6 type Router MAC1-IPv6-1 EVPN YES MAC2-IPv6-2 EVPN NO MAC4-IPv6-4 dyn NO MAC3-IPv6-3 sta YES MAC1/IPv6-1 Router MAC1/IPv6-1 NA R=1 MAC2/IPv6-2 Ext-com R=0 PE3 MAC-VRF1MAC-VRF1 NS: Who has IPv6-1? NA: MAC1 has IPv6-1 and it’s a router MAC- VRF1 MAC2/IPv6-2 Host R-bit has an impact on how hosts send packets off-link EVPN entries must learn the R-bit in the control plane ND ext-comm propagates the R-bit MAC2/IPv6-2 NA R=0 MAC4/IPv6-4 Host

6 Proxy-ARP/ND in EVPN IETF92 – March 2015 Conclusions and next steps WG feedback requested

7 Proxy-ARP/ND in EVPN IETF92 – March 2015