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Routing & Switching

Per VC Frame Relay QoS

QoS parameters can be set on Frame Relay interfaces or subinterfaces using MQC commands. The disadvantage is that the policy applies to all the traffic of the interface, and not per virtual circuit (DLCI). For this purpose, the concept of Frame Relay map-classes was developed. A map-class contains configuration information …

LFI for MultiLink PPP

1.LFI for MultiLink PPP on Serial Interfaces PPP Multilink LFI (Link Fragmentation and Interleaving) allows a router to send big frames fragmented so that smaller, delay sensitive packets can be send between these fragments of larger frames. If LFI is not enabled, a packet would have to wait for the …

IP RTP Priority

1. IP RTP Reservation IP RTP Reserve adds RTP traffic to the RSVP-reserved Queues of WFQ. These queues have a weight of 128, but RTP traffic will still have to compete with other RSVP flows for the bandwidth. Additionally, traffic that exceeds the configured RTP-BW will be treated as traffic …

CBWFQ

Class Based WFQ is configured using MQC. With CBWFQ, you use the same idea of Weighted Fair Queueing, only this time, instead of using the IP_Priority to assign a weight for each flow, like in Flow-Based WFQ, you can classify traffic on different criteria and then assign a weight for …

Enhanced Object Tracking

Object tracking is an IOS feature that allows separation between the object that is tracked and the action to be tacken when the status of that object changes. The objects to be tracked are identified by a NUMBER and different client applications (HSRP, GLBP, VRRP) can track the staus of …

Tunnel Interfaces

1. Tunnel Modes A tunnel makes two distant devices appear directly connected over a logical interface. When a packet is sent out on the tunnel interface, it is encapsulated in the “carrier” protocol and sent over a physical interface.The most used carrier protocols are GRE, IP-in-IP and IPv6, and this …

More BGP

1. Route Dampening It is used to stop unstable routes from being forwarded throughout the network. When a route flaps, a penalty is assigned to the route (Default: 1000 per flap). A timer called Half-Life is used to reduce the penalty value to half (Default: 15 min). If the penalty …

Interconnecting IPv6 and IPv4

1. Dual Stack Dual Stack means running both IPv4 and IPv6 on the same interface. This doesn’t mean they are actually interconnected, just that they can both run at the same time on an interface. 2. Tunnels 2.1 Manual Tunnels 2.1.1 IPv6 in IP Tunnels IPv6 can be encapsulated in …

IPv4 101

1. Setting an IP Address Any combination of IP-ADDR and NETMASK can be used as long as the host portion of the address is not all zeros. One exception is allowed, when using a /31 mask. By default, the router will accept combinations that result in a subnet portion of …

AutoInstall

1.AutoInstall Process The autoinstall process discribed in the following paragraphs is used in autoconfiguration of a clean router (no config) over an IP network. The following flowchart best describes this process: Here are some details about the AutoInstall steps: 1.1 Assign IP Address The first step in the AutoInstall process …