A flow might be partially switched instead of completely switched in these situations: • If the switch is configured as a member of the IP multicast group on the RPF interface of the multicast source (using the ip igmp join-group command). • During the registering state, if the switch is the first-hop router to the source in PIM sparse mode (in this case, the switch must send PIM-register messages to the rendezvous point [RP]). • If the multicast TTL threshold is ..
Security is one of the most important features of a wireless LAN. Companies and home users must protect their information from hackers. The 802.11 standard offers security mechanisms that have undergone significant scrutiny over the past few years. Recently, improvements have been made by the Wi-Fi Alliance and via newer versions of the 802.11 standard. The most common wireless security mechanisms currently in use today are as follows: ■ Wired Equivalent Privacy (WEP) ■..
RTS/CTS and Fragmentation Summary
Table 22-3 summarizes some of the benefits and drawbacks of both RTS/CTS and fragmentation when trying to improve throughput in a wireless network. Table 22-3 Improving Throughput Using RTS/CTS and Fragmentation
918. RJ-45 Pinouts and Category 5 Wiring
You should know the details of cross-over and straight-through Category 5 (Cat 5) or Cat 5e cabling for most any networking job. The EIA/TIA defines the cabling specifications for Ethernet LANs (http://www.eia.org and http://www.tiaonline.org), including the pinouts for the RJ-45 connects, as shown in Figure 1-1. Figure 1-1. The most popular Ethernet standards (10BASE-T, 100BASE-T, and 1000BASE-T) each use two twisted pairs (specifically pairs 2 and 3 shown in Figure 1-1), ..
This section illustrates the operation of the Cisco IS-IS restart mechanism, using the network diagram shown in Figure 5-8. Both R1 and R2 are Cisco IS-IS restart/NSF-capable and are interconnected via point-to-point links. • Assume using normal IS-IS procedures, R1 and R2 have synchronized their databases and are ready for forwarding. Suppose a forwarding path exists from "source" to "destination" passing through R1 and R2, and data traffic is being forw..
