7/30/2019 Renato Recio
1/27
2012 IBM Corporation
DistributedOverlay
Virtual
Ethernet
(DOVE)Networks
RenatoRecio
IBMFellow&
SystemNetworking
CTO
7/30/2019 Renato Recio
2/27
2012 IBM Corporation2
Campus
Access Layer
Aggregation Layer
Core Layer
EarlyEthernetCampusEvolution
Inthebeginning,Ethernetwasusedto
interconnectstations(e.g.dumbterminals),
initiallythroughrepeater&hubtopologies,
eventuallythroughswitchedtopologies.
Ethernetcampusesevolvedintoa
structurednetworktypicallydivided
intoaCore,Service(e.g.firewall),
Aggregationand
Access
Layer.
TrafficpatternismostlyNorthSouth(directedoutsidecampusvs peerpeer).
Toavoidspanningtreeproblems, campus
networks
typically
are
divided
at
access.
WAN
5%
95%
Layer3
Layer2
7/30/2019 Renato Recio
3/27
2012 IBM Corporation3
Layer2
Layer2
SAN
EthernetintheDataCenter
Thesamestructurednetworktopologies
wereusedinthedatacenter, but
TrafficpatternismostlyEastWest(e.g.ApplicationtoDatabasetier).
Largelayer
2domains
needed
for
clusteringandVirtualMachinemobility.
PartlyduetoEthernetlimitations
(e.g.lack
of
flow
control),
the
data
center
usedadditionalnetworks,suchas
FibreChannelStorageAreaNetworks(SAN)
InfiniBandclusternetworks.
WAN
Data Center
Access Layer
Core Layer
Aggregation Layer
> 75%