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Virtual Networking Services and Application Services - 7

a CCNA Cloud CLDFND 210-451 summary

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Mushtaq Smb
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2 min read

  1. Data center networking services include,

    • ADC or SLB (Server load balancers)

      Application Delivery Controller is a network component that manages and optimizes how client machines connect to web and enterprise applications.

    • Advanced routers
    • Firewall
    • Intrusion prevention system
    • WAN acceleration

  2. Enhancements of vPath over service insertion methods such as VLAN manipulation, PBR (Policy Based Routing) and WCCP (Web Cache Control Protocol),

    image.png

    • Performance,
    • Service chains
    • Policy based forwarding
    • Traffic offload

  3. Differences between VSG and ASAv?

    Virtual Security Gateway

    Adaptive Security Virtual Appliance

    • VSG policies can be executed inside the hypervisor kernel
    • ASAv must analyze every packet from a connection

  4. CSR 1000V runs on IOS XE network operating system.

  5. Advantages of using ADCs (Advanced delivery controllers)

    • Acceleration
    • Content switching
    • High availability
    • Scaling

  6. Required configuration elements when deploying server load balancing in Citrix NetScaler 1000V,

    • Virtual IP address,
    • Monitor,
    • Servers

  7. The following are WAN acceleration algorithms/methods available on vWAAS,

    • Windows printing AO (Application optimization)
    • DRE (Data Redundancy Elimination)
    • PLZ (Persistent Lempel-Ziv)
    • TFO (TCP Flow Optimization)

NOTE - TFC is not.

  1. Following virtual networking services support vPath (Virtual data path),

    • VSG
    • vWAAS
    • NetScaler 1000V

  2. Following solutions are components of Cisco Virtual Application Cloud Segmentation,

    • Nexus 1000V,
    • PNSC,
    • UCS Director,
    • VSG,
    • CSR 1000V

  3. Differences between three-tier and custom virtual application containers, Additional security zones

    image.png image.png

Server Load Balancer

Keywords,

  • Monitors : SLB creates requests to check whether a service is available on a server. Example - a ICMP (Internet Control Message Protocol) or a Http GET request along with a database query.
  • Virtual IP ( VIP ) : SLB internal IP address that is specifically used to receive end user connections. The Address is registered with DNS server to be advertised to end users.
  • Stickiness table : Optional component that stores client information such as IP address, Http cookies etc.
  • Load balancing algorithm : It is the configured method of user traffic distribution among the servers deploying the same application. Example of algorithms are round robin, least connections and hashing

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An interesting analogy for an SLB would be an airport control tower, which must identify the main characteristics of a landing airplane (user connection) before deciding which runway (server) it can use. The control tower usually applies a predefined method (algorithm) to sequence the arriving planes and must already know (monitor) if a runway is in maintenance or not.

CloudCloud ComputingCiscoserverLoad Balancing