1. Quality of Service CLASSIFICATION AND MARKING

2. What is QoS? 1.It’s a CCIE topic – but that doesn’t mean you can’t learn! 1.Understand traffic flows AB SYN SYN, ACK ACK ESTABLISHED AB TCP UDP SRC & DST IPs and Ports

3. Hardware Queue Categories of QoS 1.Classification and Marking 2.Congestion Management and Avoidance Packet(EF)Packet (AF21)Data Packet (EF)Voice Packet

4. Soft Priority Queue Soft Queue Hardware Queue Categories of QoS 1.Classification and Marking 2.Congestion Management and Avoidance 3.Shaping, Policing, and Link Fragmentation 1.Rate limiting 1.Shaping buffers offending packets while policing is a little more rough and by default drops offending packets. Packet(EF)Packet (AF21)Data Packet (EF)Voice Packet

5. QoS Fields 1.IP ToS Byte 2.CoS (802.1q and ISL) 3.WAN

6. QoS Fields 1.IP ToS Byte

7. QoS Fields 1.CoS and WAN fields 1.CoS has 3 bits to work with on the 802.1q header and ISL header 2.WAN markings aren’t’ much 1.MPLS has 3 bits to work with, Frame-Relay and ATM both have 1 bit 1.IP header maintains it’s markings, but not much good over L2 and L2.5 WAN networks

8. QoS Fields Continued… FieldLocationLength IP Precedence (IPP)IP Header3 bits IP DSCPIP Header6 bits DS FieldIP Header1 byte ToS ByteIP Header1 byte CoSISL and 802.1q header3 bits Discard Eligible (DE)Frame Relay header1 bit Cell Loss Priority (CLP)ATM cell header1 bit MPLS ExperimentalMPLS header3 bits

9. Per Hop Behaviors (PHB) DSCP Class Selector Names Binary DSCP ValuesIPP Binary ValuesIPP Names Default/CS0*000000Routine CS1001000001Priority CS2010000010Immediate CS3011000011Flash CS4100000100Flash Override CS5101000101Critical CS6110000110Internetwork Control CS7111000111Network Control

10. Assured Forwarding PHB and DSCP Values Queue Class Low Drop ProbabilityMedium Drop ProbabilityHigh Drop Probability Name/Decimal/Binary 1AF11 / 10 / 001010AF12 / 12 / 001100AF13 / 14 / 001110 2AF21 / 18 / 010010AF22 / 20 / 010100AF23 / 22 / 010110 3AF31 / 26 / 011010AF32 / 28 / 011100AF33 / 30 / 011110 4AF41 / 34 / 100010AF42 / 36 / 100100AF43 / 38 / 100110 Expedited Forwarding PHB and DSCP Values 1.Two PHBs 1.Quick scheduling low latency queuing 2.Police to ensure EF packets do not hog all the bandwidth and/or starve the other queues. 3.Decimal 46 – Binary 101110

11. 1.AF11 / 10 / 001010 1.AF1 | 1 = 001 | 01 | 0 1.001010 = 10 2.AF43 / 38 / 100110 1.AF4 | 3 = 100 | 11 | 0 1.100110 = 38 Assured Forwarding PHB and DSCP Values Continued…

12. Modular Quality of Service CLI 1.Class map 1.Used to Classify your traffic 2.Policy Map 1.Used to Mark your traffic (and choose what to do with marked traffic) this is also where you set Congestion Management and Policing. Normally we want to keep marking as close to the source as possible, but best practices aren’t always possible… 3.Service Policy 1.Same thing as a policy-map, but you use the service-policy command on an interface to apply the policy map

13. Network Based Application Recognition (NBAR) 1.NBAR is also known as Deep Packet Inspection 2.NBAR has the ability to look past TCP and UDP ports such as the URL, MIME type in HTTP requests allowing recognition of application information 3.Ability to use regular expressions to isolate the domain or another portion 4.Use the match protocol command under a class map to use NBAR to match traffic