Ccna certification Practice Tests

261

 26.  D.  A service-level agreement (SLA) is a contracted agreement between the Internet service 

provider (ISP) and the customer. This agreement defines the level of service. SLAs are 

based on uptime, quality of service, bandwidth, and any other stipulations the customer 

might deem necessary. Uptime is usually the most important when shopping for a 

provider. SLAs are not exclusive to ISPs and their customers; anywhere there is a service 

that requires uptime, an SLA can be found.

 27.  A.  Centralized authentication of clients is a valid reason to implement a WLC. Although 

a WLC makes it easier to implement multiple SSIDs and VLANs, this task can be 

performed with autonomous WAPs, each performing its own authentication. The use of 

autonomous WAPs negates the reasons you would use a WLC because each WAP would 

be independently managed and no coordination would exist between the autonomous 

WAPs. The use of multiple SSIDs can be achieved with an autonomous WAP without a 

WLC. Multiple VLANs can also be used with an autonomous WAP without a WLC.

 28.  D.  A wireless LAN controller (WLC) keeps track of which LWAP a client has associated 

it with and centrally forwards the packets to the LWAP that’s appropriate for a client to 

access while roaming. A single SSID by itself will not support seamless roaming between 

access points. A single service set such as a basic service set will not support seamless 

roaming of wireless clients. 802.11ac is a wireless modulation specification and by itself 

does not support the seamless roaming of clients.

 29.  B.  When WAPs are introduced to the wireless LAN controller, the WLC is responsible 

for synchronizing the WAPs to a standardized IOS. This allows for uniform support 

and features of the wireless system and is dependent on the model of WAP. WLCs can 

allow for autonomous WAPs to coexist; however, a WLC’s main purpose is to manage 

lightweight access points. WLCs can be configured to work with Connected Mobile 

Experiences (CMX) for user triangulation, but a WLC cannot provide this service by 

itself. A WLC will manage the frequencies and channels for wireless clients, but using a 

WLC will not allow you to use all the wireless frequencies and channels.

 30.  D.  Only switching between campus (distribution) switches should be performed at 

the core layer. Nothing should be done to slow down forwarding of traffic, such as 

using ACLs, supporting clients, or routing between VLANs. Routing of data should be 

performed at the distribution layer of the Cisco three-tier model. Supporting clients should 

be done at the access layer of the Cisco three-tier model. The configuration of access 

should be performed at the distribution layer of the Cisco three-tier model.

 31.  A.  A star topology has a centralized switch connecting all of the devices outward like 

a star. A full mesh topology allows for a decentralized switching design, where any 

link failure will not affect switching. A partial mesh topology is normally performed 

between the layers of core, distribution, and access to allow for a single link failure while 

maintaining switching services. A hybrid topology is where several different topologies are 

employed, such as star and mesh.

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