Flashcards in Vol 2 Part 5: Network Automation Deck (52)
Software Defined Networking (SDN) categorizes networking tasks into three different planes. What are the three planes in SDN?
Data plane, control plane, management plane
What happens in the data plane, and what is it often referred to as?
The data plane, also known as the forwarding plane, relates to tasks that involve the receiving, processing, and forwarding of a message.
Encapsulation and de-encapsulation, adding and removing trunking headers, matching the destination address with MAC tables and routing tables are all data plane tasks.
What happens in the control plane?
Information supplied to the data plane controls what happens within the data plane. The control plane is any action that controls the data plane. In a traditional network, the control and data planes are distributed AKA they are autonomous per device.
Routing protocols, ARP, NDP, MAC learning, and STP are examples of control plane tasks.
What happens in the management plane?
Any protocol that allows the management of a network device falls into the management plane.
Telnet, SSH, SNMP, and Syslog are examples of management plane tasks.
On a Cisco switch, the switching logic in the data plane does not happen on the CPU. Where does this happen?
Switching logic happens on an application specific integrated circuit (ASIC).
ASICs need to be able to look up MAC tables when switching. What is the name for the special memory where the MAC table is stored so that it can be accessed by the ASIC?
Ternary Content-Addressable Memory (TCAM)
Control plane functions have been moved to a central software application as a result of new changes in technology. What is this centralized application called?
The Southbound Interface (SBI) is the interface in which the controller communicates with networking devices. It is a software interface, NOT a hardware one. Where is the SBI located?
In between the controller and a program on the networking device, allowing the two programs to communicate.
What are the 3 main Cisco SBIs, and what are they used in conjunction with?
1. OpFlex, used with ACI.
2. CLI and SNMP used with Cisco APIC-EM
3. CLI, SNMP, and NETCONF, used with Cisco software-defined access
The Northbound interface (NBI) is the interface that opens the controller so its data and functions can be used by other programs. What is created as a result of the NBI and controller communicating?
A central repository of information such as port states, topology, device list, capabilities, etc.
Representation State Transfer Application Programming Interfaces (REST APIs) enable applications to reside on different hosts. What is used to communicate and transfer data over the API, and when would a REST API be required?
HTTP messages are used to communicate and transfer data over the API. If an application is on a VM, a REST API is needed so that the controller and application can communicate.
OpenDaylight Controller, Cisco Application Centric Infrastructure (ACI), and Cisco APIC Enterprise Module (APIC-EM) are all examples of what?
Software Defined Networking (SDN) solutions
Cisco ACI uses a specific physical switch topology known as *BLANK*
spine and leaf
What are the properties of the spine switches and leaf switches with respect to how they are connected to each other? For example, each leaf switch must connect to every spine switch.
1. each leaf must connect to every spine
2. each spine must connect to every leaf switch
3. leafs cannot connect to each other
4. spines cannot connect to each other
5. endpoints can only connect to leafs
APIC-EM adds SDN capabilities to older devices that were created before ACI and APIC were created. While APIC-EM can learn and configure network devices, what is the major thing it CANNOT do?
APIC-EM does not program flows into tables or ask control planes to change how they operate
A network in which all routers and switches are in control without the use of a controller is called *BLANK*.
A centralized control plane
Cisco Software-Defined Access (SDA) creates a new way to build campus LANs by using the software-defined architectural moden defined with SDN. At the middle sits a Digital Network Architecture (DNA) Center controller. What does SDA use with DNA Center controllers for automation?
A GUI and APIs
The DNA is the controller for *BLANK* networks
The southbound interface (SBI) contains the fabric, underlay, and overlay. Within the underlay, what is created for the use of passing data through the network?
Virtual Extensible LAN tunnels (VXLAN)
The SBI contains the fabric, which is simply the combination of the underlay and overlay. What resides in the underlay, and what resides in the overlay?
The underlay consists of the network of devices and connections, both cable and wireless. This is where IP connectivity to all nodes in the fabric lays. The overlay is the mechanism to create VXLAN tunnels between SDA switches. Essentially, the overlay is the mechanism for which VXLAN tunnels are able to be created by the underlay so that devices in the underlay can communicate.
SDA fabric uses *BLANK* design as its means to support switches and VXLAN tunnels.
routed access layer design.
Remember! with SDA fabric, as a result of the routed access layer design, access layer switches are layer 3.
The DNA center will configure devices' underlay configuration to use a *BLANK* layer.
We have established that in a routed access layer, all switches act as layer 3 switches, with switches using the IS-IS routing protocol. What links between these switches are routed layer 3 links?
ALL links, to INCLUDE EtherChannel and single links.
Security within an SDA is tied to groups of users known as what? What is used to identify these groups?
1. Scalable groups
2. Scalable group tags
Due to the architecture of SDA, which of the following are no longer necessary (choose 2)?
d. Access ports
What is the database that keeps the list of Endpoint Identifiers (EIDs) and matching routing locators (RLOCs)?
Locator ID Separation Protocol (LISP)
REST-Based APIs are known as what?
The REST application acts as a server, responding to what with respect to the client?
client API calls
What are the 6 main attributes of RESTful APIs?
1. Client/server architecture
2. Stateless operation
3. Clear statement of cacheable/uncacheable
4. Uniform interface