500-490 Designing Cisco Enterprise Networks (ENDESIGN) exam Questions and Answers

The Cisco vEdge platform supports IPv6 transport (WAN) as one of its features. This means that the vEdge routers can use IPv6 addresses to establish secure control and data plane connections with other vEdge routers over the WAN network. The vEdge routers can also use IPv6 addresses to communicate with the vSmart controllers and the vManage network management system. The vEdge routers can also support IPv6 routing protocols, such as OSPFv3 and BGP, to exchange IPv6 routes with other routers in the network12.

The other features listed in the question are not supported on the Cisco vEdge platform. License enforcement is not applicable to the vEdge routers, as they do not require any license to operate. Reporting is a function of the vManage network management system, which collects and displays various statistics and analytics from the vEdge routers. Non-Ethernet interfaces, such as serial, T1/E1, or DSL, are not available on the vEdge routers, which only support Ethernet and cellular interfaces. Single sign-on and 2-factor authentication are not supported on the vEdge routers, which use local or remote authentication methods, such as TACACS+, RADIUS, or LDAP3.

References:

1: Cisco SD-WAN vEdge Routers Data Sheet 2: Cisco SD-WAN Configuration Guide, Release 20.3 3: Cisco SD-WAN Command Reference, Release 20.3

 Cisco ISE is a comprehensive solution that enables enterprises to enforce consistent and secure access policies across wired, wireless, and VPN connections. It also provides visibility, control, and automation for the network devices, endpoints, users, and applications. To sell Cisco ISE effectively, it is important to highlight the benefits and features of the solution that address the customer’s pain points and needs. Among the options given, two options help you sell Cisco ISE:

• Showcasing the entire ISE feature set: ISE has a rich and diverse feature set that covers various use cases, such as device management, asset visibility, software-defined segmentation, software-defined access, guest and wireless access, BYOD, posture assessment, threat detection and response, and more1. By showcasing the entire ISE feature set, you can demonstrate the value proposition and differentiation of ISE from other solutions, and how it can help the customer achieve their business and technical goals.
• Explaining ISE support for 3rd party network devices: ISE is not limited to Cisco networks only. It can also support 3rd party network devices that comply with the standard protocols and interfaces, such as RADIUS, SNMP, TACACS+, 802.1X, MAB, CoA, and EAP2. By explaining ISE support for 3rd party network devices, you can show the customer that ISE is a flexible and interoperable solution that can work with their existing network infrastructure, and that they do not need to replace their non-Cisco devices to deploy ISE.

The other three options are not helpful for selling Cisco ISE:

• Referring to TrustSec as being only supported on Cisco networks: TrustSec is a Cisco technology that enables software-defined segmentation based on security group tags (SGTs) and security group access control lists (SGACLs)3. TrustSec is not only supported on Cisco networks, but also on 3rd party network devices that can integrate with ISE through pxGrid, which is a platform for sharing contextual information across multiple security products4. By referring to TrustSec as being only supported on Cisco networks, you can create a false impression that ISE is a proprietary and closed solution that requires a complete Cisco network overhaul, which can discourage the customer from adopting ISE.
• Discussing the importance of custom profiling: Profiling is a feature of ISE that allows it to identify and classify the endpoints on the network based on their attributes, such as MAC address, IP address, device type, operating system, etc.5. Custom profiling is the ability to create custom profiles and policies for the endpoints that are not recognized by the default ISE profiles. While custom profiling is an important feature of ISE, it is not a key selling point, because it is a complex and time-consuming process that requires a deep understanding of the endpoint attributes and behaviors, and it may not be relevant or applicable for all customers. By discussing the importance of custom profiling, you can confuse or overwhelm the customer with technical details that are not essential for their use case, and divert their attention from the core benefits and features of ISE.
• Downplaying the value of pxGrid as compared to RESTful APIs: pxGrid is a platform that enables ISE to share contextual information, such as identity, location, posture, device type, etc., with other security products, such as firewalls, SIEMs, threat detection systems, etc.4. RESTful APIs are a standard way of communicating with web services, such as ISE, using HTTP methods, such as GET, POST, PUT, DELETE, etc… Both pxGrid and RESTful APIs are valuable for ISE, because they provide different capabilities and benefits. pxGrid allows ISE to exchange real-time and bidirectional information with other security products, and to enforce consistent policies across the network4. RESTful APIs allow ISE to be integrated with external applications and systems, such as portals, dashboards, workflows, etc., and to automate and customize the network operations. By downplaying the value of pxGrid as compared to RESTful APIs, you can misrepresent the functionality and potential of ISE, and miss the opportunity to showcase how ISE can enhance the security and efficiency of the network.

References:

Cisco Identity Services Engine (ISE) Use Cases1 : Cisco Identity Services Engine Network Component Compatibility, Release 2.72 : Cisco TrustSec3 : Cisco pxGrid4 : Cisco ISE Network Discovery5 : Cisco Identity Services Engine Administrator Guide, Release 2.7 - Configure Custom Profiling Policies [Cisco Identity Services Engine] - Cisco : Cisco Identity Services Engine API Reference Guide, Release 2.7 - Cisco ISE REST APIs [Cisco Identity Services Engine] - Cisco

SD-Access and ACI Fabric are both solutions that provide software-defined networking for different domains. SD-Access is designed for the campus and branch networks, while ACI Fabric is designed for the data center networks. However, they share some common features and concepts, such as:

• Use of Scalable Group Tags: Both SD-Access and ACI Fabric use Scalable Group Tags (SGTs) to identify and classify the endpoints based on their attributes, such as user identity, device type, or application. SGTs are numerical labels that are assigned to the endpoints and carried in the packets, either in the header or in the metadata. SGTs enable granular and dynamic policy enforcement based on the endpoint identity and context, rather than the network topology and IP addresses12.
• Use of overlays: Both SD-Access and ACI Fabric use overlays to create a network abstraction layer that decouples the network services and functions from the underlying physical infrastructure. Overlays enable network virtualization and segmentation, as they allow multiple logical networks to coexist on the same physical network. Overlays also simplify the network design and management, as they reduce the complexity and variability of the network elements and interfaces. SD-Access uses VXLAN as the overlay protocol, while ACI Fabric uses VXLAN with EVPN as the overlay protocol34.
• Use of Endpoint Groups: Both SD-Access and ACI Fabric use Endpoint Groups (EPGs) to group the endpoints based on their policy requirements and network scope. EPGs are logical containers that define the allowed interactions between the endpoints, such as the protocols, ports, and quality of service. EPGs also define the network boundaries that isolate the endpoints from each other, based on the security and compliance needs. EPGs are synonymous with Scalable Groups in SD-Access, and they can be mapped between SD-Access and ACI Fabric to enable end-to-end policy across the domains56.

References:

• Cisco TrustSec Overview
• Cisco TrustSec Configuration Guide, Cisco IOS XE Gibraltar 16.12.x - Scalable Group Tags [Cisco IOS XE 16] - Cisco
• Cisco SD-Access Architecture Overview
• Cisco Application Centric Infrastructure Fundamentals, Release 4.0(1) - ACI Fabric Fundamentals [Cisco Application Policy Infrastructure Controller (APIC)] - Cisco
• Cisco SD-Access (SDA) Integration with Cisco Application Centric Infrastructure (ACI) - Cisco Community
• Cisco Application Centric Infrastructure - Cisco Multidomain Integration At-a-Glance

= Border nodes are the component of the SD-Access fabric that is responsible for communicating with networks that are external to the fabric. Border nodes serve as the gateway between the fabric domain and the network outside of the fabric. Border nodes are responsible for network virtualization inter-working and SGT propagation from the fabric to the rest of the network1. Border nodes also perform LISP Proxy Tunnel Router (PxTR) functions, which convert policy and reachability information, such as SGT and VRF information, from one domain to another2. Border nodes can connect to internal networks, such as data center or WAN, or external networks, such as internet or cloud3.

Edge nodes, control plane nodes, and intermediate nodes are not responsible for communicating with networks that are external to the fabric. Edge nodes are the access-layer switches where all of the endpoints reside. Edge nodes detect clients and register them with the control plane nodes. Edge nodes also provide an anycast L3 gateway for the connected endpoints and perform encapsulation and de-encapsulation of data traffic4. Control plane nodes are the devices that run a host tracking database to map location information. Control plane nodes receive endpoint ID map registrations from edge and/or border nodes and resolve lookup requests from edge and/or border nodes to locate destination endpoint IDs5. Intermediate nodes are the devices that provide underlay connectivity between edge nodes and border nodes. Intermediate nodes do not participate in the fabric overlay and do not have any fabric roles6.

References :=

• Role of Fabric Border Node & IS-IS protocol in Cisco SD-Access
• Software Defined Access Network Fabric Roles - Study CCNP
• Cisco SD-Access
• SD-Access Fabric Troubleshooting Guide - Cisco
• Cisco SD-Access Solution Design Guide (CVD) - Cisco
• Cisco SD-Access Solution Design Guide (CVD) - Cisco
• Cisco SD-Access Solution Design Guide (CVD) - Cisco

 The new operational paradigm is a way of designing, deploying, and managing networks that leverages the power of intent-based networking. Intent-based networking is a network architecture that aligns the network with the business goals and policies, and uses artificial intelligence and automation to translate the intent into network configurations and actions. The new operational paradigm requires three foundational elements:

• Fabric: A fabric is a network topology that consists of interconnected nodes that provide a consistent and scalable way of delivering network services and functions. A fabric can span across multiple domains, such as campus, branch, data center, and cloud, and can support multiple protocols, such as IP, Ethernet, MPLS, and VXLAN. A fabric enables the network to operate as a single entity, rather than a collection of disparate devices and links. A fabric also simplifies the network design and management, as it reduces the complexity and variability of the network elements and interfaces.
• Assurance: Assurance is the process of continuously monitoring, verifying, and optimizing the network performance and behavior, based on the defined intent and policies. Assurance uses telemetry, analytics, and machine learning to collect and process data from the network devices and applications, and to provide insights and recommendations for network optimization and troubleshooting. Assurance also enables the network to self-heal and self-optimize, by applying corrective actions and adjustments to the network configurations and policies, based on the feedback loop from the data and analytics.
• Policy-based automated provisioning of network: Policy-based automated provisioning of network is the process of applying the intent and policies to the network devices and services, using automation and orchestration tools. Policy-based automated provisioning of network abstracts the network complexity and heterogeneity, and allows the network operators to define the network requirements and outcomes in a high-level and declarative way, rather than specifying the low-level and imperative commands and parameters. Policy-based automated provisioning of network also enables the network to be agile and adaptive, as it can dynamically adjust the network configurations and policies, based on the changing network conditions and business needs.

References:

• Cisco Intent-Based Networking
• Cisco Digital Network Architecture
• Cisco Routed Optical Networking
• Cisco Operational Insights: A New Way of Seeing Operations

Cisco SD-WAN vEdge routers can mitigate DoS attacks against the infrastructure by using two mechanisms:

• Only authorized controllers are allowed to communicate back to the vEdge router after the vEdge router establishes connection with the controllers. This means that the vEdge router initiates a secure connection to the vSmart controller and the vBond orchestrator using DTLS or TLS, and verifies their identity using certificates. The vEdge router does not accept any incoming connections from the controllers, and only responds to the messages that match the established sessions. This prevents unauthorized or malicious traffic from reaching the vEdge router and consuming its resources12.
• By default, all incoming traffic is denied at the transport (WAN) side interfaces. This means that the vEdge router applies an implicit deny-all policy to any traffic that arrives from the WAN side, unless it is explicitly allowed by a security policy. The security policy can be configured to permit only the traffic that matches certain criteria, such as source, destination, protocol, port, or application. This reduces the attack surface of the vEdge router and protects it from unwanted or harmful traffic34.

References:

• Cisco SD-WAN Security Features
• Cisco SD-WAN Design Guide
• Cisco SD-WAN Security Policy Configuration Guide
• Cisco SD-WAN vEdge Routers Denial of Service Vulnerability

The Cisco Catalyst 9500 Series Switches are specifically built to address the new challenges faced by enterprises, such as the need for increased bandwidth, security, and scalability. The Catalyst 9500 Series Switches are also designed to support Cisco SD-Access, which is a software-defined access fabric that simplifies network management and improves network security.

References: =

• Designing Cisco Enterprise Networks (ENDESIGN): https://www.cisco.com/c/en/us/training-events/training-certifications/training/training-services/courses/designing-cisco-enterprise-networks-ensld.html
• Cisco Catalyst 9500 Series Switches: https://www.cisco.com/site/us/en/products/networking/switches/catalyst-9500-series-switches/index.html