A Thousand-Dollar Networking Definitions

I gather in this blog post different networking definitions a network engineer may encounter (or may not, what a shame, LOL) in his journey. It will be a short article but bare with me, there are tricky nuances!

Layer 2 domainthe network formed by the sum total of switches, hubs and any layer 2 devices in a network. The layer 2 domain is delimited by the existence of a device performing a layer 3 (routing) function.
Administrative layer 2 domainthe layer 2 domain – or part thereof – that a network engineer manages.
L2 segmenta portion of the layer 2 domain. It is usually defined by either VLAN or VXLAN technology.
VLAN segmentthe collection of network hosts and nodes that belong to the same VLAN ID. Hosts on one VLAN segment “A” can not communicate inherently with hosts on a VLAN segment “B” unless there is a routing component (a layer 3 gateway) that performs inter-VLAN routing.
Multitenant datacentera datacenter where multiple organisations, or departments within an organisation, share the resources of the same datacenter infrastructure network.
Workloada logical block that consumes datacenter resources: compute, storage and network.
BUM trafficLayer 2 Broadcast traffic +Unknown Unicast traffic (which is also a broadcast traffic type) + layer 2 Multicast traffic.
Unknown Multicast traffica multicast traffic that matches no entry in the multicast table.
Config/fault domainthe area of the network that is impacted by a configuration policy or a fault.
Live Migrationa software-defined datacenter feature offered by Microsoft. It is moving a compute workload from a virtualization server/cluster to another one, without powering off the workload.
Vmware has a similar feature called vMotion.

Leave a Comment