Potential ISP Bottlenecks and Subscription Ratios
The provider's network is only as strong as its weakest link. There are two potential ISP bottlenecks: oversubscription of backbone trunks and small tail circuits leading to a POP or downstream customer. A provider should not recklessly oversubscribe its connections. ISPs that attempt to save money by overloading their routers or connections will end up losing credibility in the long run. Oversubscription occurs when the cumulative utilization of multiple links exceeds the b..
RSVP is a soft-state signaling system that enables receivers to reserve resources for incoming traffic flows. Flows are identified by destination address and the transport-layer protocol, and are, therefore, unidirectional. The destination address can be a multicast group address; therefore, from an RSVP perspective, unicast flows are simply a special case of multicast. More specifically, in the unicast case, it is not necessary for a host to join a group prior to reserving r..
QoS is disabled by default; however, the radio interface always honors tagged 802.1P packets even when you haven't configured a QoS policy. QoS can be configured through either the Cisco IOS (MQC) CLI or the web-interface configuration utility provided by the AP software. The Cisco IOS MQC CLI provides a very familiar syntax for QoS configuration on Cisco APs. In Example 11-2, DSCP EF is mapped to IEEE 802.1D CoS 6 (the IEEE definition for voice CoS) and is applied to the IE..
Congestion Indication Support in FRF.8.1
For FRF.8.1, Cisco supports the bidirectional mapping of FECN and EFCI bits outlined in Table 8-5. Table 8-5. Table 8-5. EFCI and FECN Mapping for FRF.8.1 Frame Relay to ATM Direction Default The EFCI field in the ATM cell header is set to 1 if the FECN field in the Frame Relay headers is set. User configurable The EFCI field in the ATM cell header is set to a constant 0. ATM ..
The ip rip triggered interface configuration command tells the router to only send those parts of the RIP database that have changed, instead of sending the entire database on each RIP update cycle: Router1#configure terminal Enter configuration commands, one per line. End with CNTL/Z. Router1(config)#interface Serial0/0.2 Router1(config-subif)#ip rip triggered Router1(config-subif)#end Router1# Be sure to enable these nonperiodic "triggered" updates on the adjacent ro..
