Routing. Static Routing. Fairness. Adaptive Routing. Shortest Path First. Flooding, Flow routing. Distance Vector

Transcription

1 CSPP 57130

2 Routing Static Routing Fairness Adaptive Routing Shortest Path First Flooding, Flow routing Distance Vector

3 RIP Distance Vector Sometimes called Bellman-FOrd Original Arpanet, DECNet, Novell, AppleTalk One entry for each router in network Next hop and distance

4 RIP Limitations Counting to Infinity Good news is fast, but bad news is slow Split Horizon hack Link State Routing Track all links, not just nearest neighbor More data to track, computation can be time consuming for large networks

5 Hierarchical Routing The Internet Today BGP-4 among ISPs Link State for large corporate nets Distance vector/static for small office network

6 Quality of Service Switching CoS is a 3 bit field within an Ethernet frame header when using 802.1Q tagging. Routing IP bits

7 IP Precedence Bits 0 0 Routine 1 1 Priority 2 10 Immediate 3 11 Flash Flash Override Critical Internetwork Control Network Control

8 Diff Services IP V 6 Calass byte Differentiated Services Code Point (DSCP)

9 Diff Server Components Classifier -- Identifies a packets class Marker -- Writes DSCP field of packet Metering -- Compliance of traffic profile Shaper -- delays traffic by buffering some Dropper -- drops appropriate traffic

10 QoS on a 3750 interface FastEthernet0/19 description Conf rm 17E White switchport access vlan 37 switchport trunk encapsulation dot1q switchport trunk native vlan 37 switchport mode trunk switchport voice vlan 27 switchport priority extend cos 0

11 QoS on a Router Classify packets class-map match-all others match any class-map match-any rtp-out match ip dscp ef match ip precedence 5 class-map match-all voice-control match access-group name voicecontrol class-map match-all rtp match ip rtp class-map match-any voice-control-out match ip dscp af31 match access-group name voicecontrol

12 Mark packets QoS on a Router policy-map voice-policy-out class rtp-out priority 738 class voice-control-out bandwidth 8 class class-default fair-queue policy-map classify-voice class rtp set dscp ef class voice-control set dscp af31 class others set dscp default policy-map slc-voice-policy-out

13 QoS on a Router Implement the Policy Frame Relay Port interface Serial0/1 description CHI-SLC-SF Frame (DHEC ATI) no ip address encapsulation frame-relay no ip mroute-cache load-interval 30 service-module t1 timeslots 1-24 frame-relay traffic-shaping frame-relay lmi-type ansi

14 QoS on a Router Implement the Policy Frame Relay port (cont.) interface Serial0/1.3 point-to-point description CHI/SanFran Frame (DHEC ATI) bandwidth 256 ip address no ip mroute-cache frame-relay interface-dlci 110 class voicefr frame-relay ip tcp header-compression frame-relay ip rtp header-compression

15 QoS on a Router Implement the Policy Frame class voicefr map-class frame-relay voicefr frame-relay cir frame-relay bc 7680 frame-relay be 0 frame-relay mincir frame-relay fragment 1600 service-policy output voice-policy-out!

16 QoS on a Router A Point-to-Point link interface Serial0/0 description NY point-to-point WAN bandwidth 1536 ip address service-policy output voice-policy-out no ip mroute-cache load-interval 30 service-module t1 timeslots 1-24 service-module t1 fdl att

17 Implementing QoS Download a formula from Vendor Might need tweaking for local conditions

18 Cisco 3750 Traffic Shaping Weighted Tail Drop three Thresholds CoS 5 100% No packets dropped unless full CoS % drop threshold CoS % drop threshold

19 Cisco 3750 Cont. Four hardware egress queues Shaped Round Robin Aggregate rate shaping Specify maximum combined transmission rate for all four queues Individual rate shaping Queues not shaped are shared by SRR

20 Cisco 3750 Cont. Traffic Policing Like shaping, but no buffer Traffic beyond limit is dropped non-blocking switch fabric Two ingress queues Strict priority traffic, other traffic

21 Port Monitoring Cisco Switched Port Analyzer (SPAN) Packet sniffing problem on switches Only get flooded and broadcast packets Monitor ports Limits for each device 2900/3500XL one port, no vlan, no trunk, no channel group, no psec

22 SPAN on 3750 conf t monitor session 1 source inter faste 0/2 monitor session 1 destination inter faste 0/3 exit; show monitor session 1