Network Topology Architechures Flashcards
What is a 2 Tier Architecture?
Is Enterprise Topology
Core and distribution are flattened to one tier
Access is one tier - Port Density and BW here
Distribution/Core - QoS and ACLs here
North to south
Is a hybrid design that uses star at access layer and partial mesh at distribution layer
What is a 3 Tier Architecture?
Enterprise architecture
Acces - high port density to PCs- no inspection just acess to the distribution layer
Distribution - does QoS, ACL (want to halt traffic as close to the Access Layer as possible so doesnt get to Core and doesn’t use bandwidth if not need it)
Core - pass traffic quickly to go to downstream LANs - doesnt inspect traffic as much
North to south
What is a leaf and spine architecture?
Data Center design
Most traffic goes to servers
Traffic is from east to west inside DC btw servers through the spine/leaf
Leaf has multiple uplinks to every spine - for BW
Usually all is running at L2 OR all running at L3
What is the core tier?
Responsible to get connectivity quickly to downstream LANs
What is the distribution tier?
L3 is introduced (usually - could be at Access - but not usually)
Agreggate all the traffic that the Access is sending up - need high bandwidth links to carry all the EU traffic coming in from the access tier
Want switches with less ports but high bandwidth on the ports
Introduce QoS, ACLs
Smarter layer than the access layer
What is the access tier?
Bottom tier
Tier facing the EUs (facing the PCs)
Job is to provide access using switches that are very high port density
Switchs at Access layer have: lots of ports and lots of bandwidth
Switches here DON’T have: QoS, ACL, etc
On Prem Architecture
Say have PC connected to switch
Switch Connected to router
That router connected to another switch
That switch is connected to email server
All speaking locally and the email server is the only thing that goes out to internet to download emails
What is Cloud Infrastructure?
Lets say that email server is costly to upkeep or equipment expensive or its not reliable
Also maybe dont have skillset to maintain the email server
Move the email server into the cloud.
Have secure method to put email server in someone else’s cloud (like AWS, Azure, Google, etc) - its not on OUR premise
Other company maintains the server (like maybe RAM or CPU) - may be cheaper or may be more expensive
What is a star topology
One central dev connects to sever others in shape of Sar
Often seen at Access Layer in both 2- and 3-tier model
At 3-tier model - core usually has star
What is a Full Mesh Topology?
A design that connects a link between each pair of nodes.
Often seen at distribution layer
What is a partial mesh topology?
Connects a linke between some pairs of nodes but not all.
Is a mesh that is not a full mesh.
Usually seen btw the layers of core, distribution and access layer
What is a hybrid topology?
A design that combines topology design concepts into larger design
Most comonly seen at Access Layer - (Devices connected in star and access switches partially meshed to distribution switches)
