1.7 Corporate and Datacenter Network Architecture

Question 1

The Core Layer.

Answer 1

The core layer should be the fastest bandwidth and nothing should be done to slow traffic down; only routing and switching should occur at the core layer.

Question 2

The Distribution Layer.

Answer 2

The distribution layer is where packet filtering, routing of VLANs, and the control plane are located.

Question 3

The Access Layer.

Answer 3

The access layer is for client connectivity and where you find PoE, QoS, and other client protocols.

Question 4

The Collapsed Core Model.

Answer 4

The collapsed-core model combines the core and distribution layers.

Question 5

The Application Layer of Software Defined Networks (SDN).

Answer 5

The Application layer is where applications and the API are located that control the infrastructure.

Question 6

The Northbound Interface (NBI).

Answer 6

The northbound interface (NBI) is a component of the SDN controller, which allows API and application access.

Question 7

The Control Layer of Software Defined Networks (SDN).

Answer 7

The control layer is basically the SDN controller; everything is controlled at this layer.

Question 8

The Southbound Interface (SBI).

Answer 8

The southbound interface (SBI) is a component of the SDN controller that allows it to communicate with the infrastructure.

Question 9

The Infrastructure Layer of Software Defined Networks (SDN).

Answer 9

The infrastructure layer is where you will find the various hardware devices that are controlled by the SDN controller.

Question 10

The Management Plane.

Answer 10

The management plane is used to manage devices and stretches across all layers.

Question 11

Spine-leaf Switching.

Answer 11

Spine-leaf switching is found in data centers to provide fast, scalable networks for data center equipment.

Question 12

Spine Servers.

Answer 12

Spine servers connect to each leaf switch and never connect hosts or other network equipment.

Question 13

Leaf Switches.

Answer 13

Leaf switches only communicate with spine switches and never directly with other leaf switches. Leaf switches are always within two hops from their destination via the spine switch

Question 14

Underlay and Overlay.

Answer 14

The underlay is an IP address–based network, and the overlay is normally a VXLAN to encapsulate the original packet for IP transit across the underlay.

Question 15

Traffic Flow.

Answer 15

Routed traffic flows South to North and switched traffic flows East to West.

Question 16

Data Center Traffic.

Answer 16

Data center traffic should always flow East to West to minimize latency.

Question 17

Client or Internet Traffic.

Answer 17

Only traffic to the clients or Internet should flow South to North.

Question 18

Public Cloud Hosting

Answer 18

Advantage: Flexible.
Disadvantage: Monthly Fee.

Question 19

Company-Owned Data Center.

Answer 19

Advantage: Greatest control.
Disadvantage: Costly, space required.

Question 20

Branch Office.

Answer 20

Advantage: Disaster Recovery.
Disadvantage: Must use WAN technologies, Sometimes slow connections, no full-time admin.

Question 21

Colocation.

Answer 21

Advantage: Off-site backup and disaster recovery.
Disadvantage: Monthly Expense.

Question 22

Network Attached Storage (NAS).

Answer 22

Network attached storage (NAS) is a file-level storage system. NAS requires a higher-level protocol called the filer to process file requests.

Question 23

Storage Area Networks (SAN).

Answer 23

Storage area networks (SANs) are block-level storage systems. SAN storage allows the host to access a LUN directly and read and write at the data block level.

Question 24

Storage Area Networks (SAN) two main types.

Answer 24

The two main types of SAN are Fibre Channel and iSCSI.

Question 25

Fiber Channel Connection.

Answer 25

Fiber Channel normally required dedicated FC switches and was designed for wire speeds and lossless connections for storage.

Question 26

Fiber Channel over Ethernet connection.

Answer 26

With Fiber Channel over Ethernet, a single Ethernet cable carries both the Ethernet traffic and the Fiber Channel traffic.

Question 27

iSCSI Connection.

Answer 27

iSCSI is becoming a popular replacement for Fiber Channel because existing Ethernet data center switching can be used for connectivity.

Question 28

InfiniBand Connection.

Answer 28

InfiniBand requires a similar fabric as Fibre Channel and was created for high-performance computing.