ONT Notes – Pre-classify and End-to-end QoS

• VPNs (Didn’t ISCW cover this?)
  • Provide
    • Confidentiality
    • Integrity
    • Authentication
  • Types
    • Remote-access
      • Client-initiated
      • NAS-initiated
    • Site-to-site
      • LAN-to-LAN
      • Extranet
• L3 Tunneling protocols
  • GRE
  • IPSec
• Pre-classify allows traffic to be classified before being sent across a tunnel or crypto-ed.
  • qos pre-classify
  • Provides a view into the original IP headers
  • To classify on pre-tunnel header, apply the policy to the tunnel interface WITHOUT pre-classify.
  • To classify on post-tunnel header, apply the policy to the physical interface WITHOUT pre-classify.
  • To classify on pre-tunnel header, apply the policy to the physical interface WITH pre-classify.
• SLA – agreement with provider to guarantee QoS mechanisms across their network based on your markings.
  • Assures availability, loss, throughput, delay, and jitter.
• End-to-end QoS
  • To be effective, each hop in the path must have QoS configured similarly.
  • Necessary in three locations
    • Campus – within the customer network
    • The edges – customer facing the provider, provider facing customer
    • On the provider network
• QoS tasks
  • Campus access switches
    • Speed/duplex settings
    • Classification
    • Trust
    • Phone/access switch configs
    • Multiple queues on switch ports, including priority for VOIP
  • Campus distribution
    • L3 policing and marking
    • Multiple queues on switch ports, including priority for VOIP
    • WRED
  • WAN edge
    • SLA definitions
    • LLQ
    • LFI
    • WRED
    • Shaping
  • Provider cloud
    • Capacity planning
    • PHB
    • LLQ
    • WRED
• Enterprise campus QoS implementation
  • Implement multiple queues to avoid congestion
  • Assign VOIP and video to highest priority queue
  • Esablish trust boundaries
  • Use policing to rate-limit excess traffic
  • Use hardware QoS when possible
• Control Plane Policing (CoPP)
  • Applies QoS policy to traffic destined for the router
    • Routing protocols
    • Management protocols
  • Can be used to avoid DOS attacks
  • Applied to control-plane in global config

Aaron Conaway

I like to lean my head to the left, hit it with the palm of my right hand, and document what knowledge falls out.

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Tags: 642-845, campus, ccnp, certification, cisco, class, control plane, copp, documentation, headers, interface, ont, physical, policing, policy, pre-classify, qos, shaping, test, tunnel, voice, voip, vpn