Chapter 3


1.

How are MAC address tables built in Layer 2 switches?

Answer:

Layer 2 switches build MAC address tables by inspecting ARP traffic flowing across the switch.

2.

Do Layer 3 switches maintain an ARP cache or a MAC address table?

Answer:

Layer 3 switches maintain both an ARP cache and a MAC address forwarding table. The MAC forwarding table is used to forward frames between ports within a single VLAN, and the ARP cache is used to route frames between VLANs.

3.

What is the purpose of VTP?

Answer:

VTP saves time configuring VLANs and saves NVRAM space in large network environments. The network administrator needs only to add VLANs to the VTP server before assigning VLANs to switch ports across the entire network. VTP is also used to give VLANs human-readable names.

4.

What is the difference between distance-vector and links-state dynamic routing protocols?

Answer:

Distance-vector algorithms send periodic routing updates and use hop count metrics. Link-state algorithms send triggered updates when changes occur and use metrics based on the state of the links (that is, based on the bandwidth, delay, reliability, load, and MTU of the link).

5.

What is a RIB? Give a few examples of protocols that use RIBs.

Answer:

The routing information base stores routing information learned by link-state and hybrid-dynamic routing protocols. The best RIB routes are installed in the main routing table. OSPF, EIGRP, and BGP routing protocols maintain their own RIBs.

6.

What is a FIB? Give a few examples of switching paths that use FIBs.

Answer:

A forwarding information base is efficient data structure containing forwarding information used by routers to bypass slow(er) routing tables and ARP cache lookups. Examples of switching paths that use RIBs are fast and CEF switching. Process switching does not use a RIB.

7.

What form of NAT do content switches use to load balancing requests across server farms?

Answer:

Destination NAT is used by content switches to perform server load balancing.



Content Networking Fundamentals
Content Networking Fundamentals
ISBN: 1587052407
EAN: 2147483647
Year: N/A
Pages: 178

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