EVPN/OverlayandNetwork Architecture
Satoru Matsushima

What Networks We Have…

Access

WANDC2An E2E Architectural View of Network Service

L2/L3 customers traﬃcAccess
NodeNID

Aggregation
SwitchEthernetAccessPE
Protection w/ OAM

DataCenterMPLS
BackbonePE

ToR/vSwitch

mLAG
3An E2E Architectural View of Network Service
VLAN Stack Aggregation on Access and Data-Center networks
L2/L3 customers traﬃc
S-TAG1S-TAG1ʼS-TAG2
AccessNode

NID

S-TAG3L2/L3 VPN Label
LSP

E-LINE over MPLS(-TP)

Aggregation
SwitchEthernetAccessPE
Protection w/ OAM

Data
CenterMPLSBackbone
PEToR/vSwitchmLAG
4Issues of Tag-stacking based Ethernet AccessnVID Scalability
l 0-4096 (12bits space)l Stacking S-TAG works to enlarge VID space (12+12=24bits)l But aggregation switches still need to be deployed for each 12bits
VID spacenDeployment painsl Agg-switches become single point of failure that are increased as
network growthl Deploying 1:1 Agg-switch redundancy works to spend more money5

Getting over the issues of Ethernet networking
Emerging NVO3 and EVPN Control-plane to solve the issuesL2/L3 customers traﬃc
S-TAG1S-TAG1ʼS-TAG2Access NodeNID

L2/L3 VPN Labelnvo3 tunnel

LSPIP

E-LINE over MPLS-TPAggregation
SwitchEVPN

EthernetAccess

DataCenterMPLS
BackbonePE

Protection w/ OAM

EVPNPE

ToR/vSwitch

mLAG
6VPLS vs EVPN
VPLS (RFC4762)

EVPN(RFC7432)

VPN Signaling

LDP

BGP

MAC Learning

Data-Plane

BGP Policy

PE-CE Multi-homing

Single-Active

All-Active

Convergence

MAC Re-Learn

BGP Update

BUM

Ingress copy

Multicast7

Getting over the issues of Ethernet networking
Can NVO3 relief the pains of Ethernet Access as well?
L2/L3 customers traﬃc
S-TAG

AccessNodenvo3 tunnel?

VPN Label

VXLAN

IPLSPIPE-LINE over MPLS-TPEVPN?
NID

EVPN

IP AggEthernetAccess

DataCenterMPLS
BackbonePE

Protection w/ OAM

EVPNPE

ToR/vSwitchmLAG
8Challenges to deploy NVO3 into the AccessnAccess-node might not be EVPN capablel Due to limited resources to reduce costl No MAC learningl Is that Softbank specific?

nHow does the PE find remote NVEs without BGP?
l PPP/L2TP Signaling per tunnel? -> NO!
l Using controller? Is that scalable for 10K~ ANs deployment?

nOther issuesl Which encapsulation should be chose, e.g., VXLAN, GRE, etc.,l Multicast?
9IPv6 might help for NVE discovery
Remote NVE address can be derived from VNID
with mapped IPv6 prefix
630

Remote NVE IPv6 address

Domain Prefix

ANIDLine64-(i+j)

i

j127

Interface ID

i+j =< 24

VXLAN Encapsulation

IPv6Header

UDP

VNI

MACHeader

CVLAN

PayloadFCS10Packet Flow and Format
Dst: PE Anycast
Src: AN Addressi+j =< 24   

i+j =< 24Access
Node(AN)



 

Dst: AN Address
Src: PE Anycast
PE Anycast

LinePEWAN

IPv6 Network63

0

AN-Address   
 

64-(i+j)

ij127 

11

Multi-homing w/ Anycast routing*More Resilient Connectivity than VLAN/Pseudo-Wire
PE Anycast Address

AccessNode(AN)Line

IPv6 NetworkPE

EVPN/L3-VPN
Active-ActiveRedundancy

WAN

AN-Address* https://tools.ietf.org/html/draft-sajassi-bess-pbb-evpn-anycast-ip-tunnels-00

12

The Ambitious Network in the future
NVO3 Ethernet Access over IPv6-only Access Network
L2/L3 customers traﬃc
S-TAGAccess
NodeNID

nvo3 tunnel

VPN Label

VXLAN

IPv6!

LSP

IPv6!

LSP

Aggregation
Switches

EVPN

DataCenter

MPLS
Backbone

IPv6PE
Protection w/ OAM

EVPNPE

ToR/vSwitch

IPv6Routing
13Summaryn Pains exist not only in DC, but also in Accessn NVO3 can help to relief the pain, but…
l It depends on node’s capability and resource restrictionn Utilizing IPv6 shall suite “Light Weight” overlay
deployment for Ethernet Accessl without not only BGP but also any other signaling

nIt’s Controversial for changing VNID semantics?
l Don’t worry, MEF already did it for VID in E-Line. J14

Questions? Comments?