WAN Design
Here you will find answers to WAN Questions
Question 1
Which three factors best justify WAN link redundancy between geographically dispersed sites? (Choose three)
A. important traffic flows
B. lack of speed
C. high link utilization
D. uncertain reliability
E. excessive packet transmission rate
F. high expense of transmitting data
Answer: A B D
Question 2
Which of these accurately describes dial backup routing?
A. it always uses distance vector routing protocols
B. it always uses permanent static routes
C. the router inflates the dial backup link when a failure is detected on the primary link
D. it is supplied by the setvice provider as a secondary PVC at no additional charge
E. once the backup link is activated it will remain active even after the primary link is restored
Answer: C
Question 3
Refer to the exhibit.
Which module is the Enterprise WAN module?
A. Enterprise A
B. Enterprise B
C. Enterprise C
D. Enterprise D
E. Enterprise E
F. Enterprise F
Answer: C
Question 4
Western Associated News Agency recently acquired a large news organization with several sites, which will allow it to expand to worldwide markets. The new acquisition includes these connectivity technologies:
Frame Relay
ATM
SONET
cable
DSL
wireless
From a Layer 1 viewpoint, which Enterprise Edge module will be most affected?
A. ISP
B. PSTN
C. E-Commerce
D. WAN/MAN
E. Edge Distribution
F. Internet Connectivity
Answer: D
Question 5
Which three mechanisms are required to deploy QoS on an IP WAN? (Choose three)
A. traffic classification
B. Call Admission Control
C. queuing and scheduling
D. link efficiency techniques
E. traffic shaping
F. bandwidth provisioning
Answer: B D E
Question 6
Which three types of WAN topologies can be deployed in the Cisco Enterprise Architecture Enterprise Edge WAN module? (Choose three)
A. ring
B. star
C. full mesh
D. core/edge
E. collapsed core
F. partial mesh
Answer: B C F
Question 7
Which two of these best describe the implementation of a WAN Backup design over the Internet? (Choose two)
A. a best-effort method
B. requires no ISP coordination or involvement
C. bandwidth guaranteed based on interface configuration
D. designed as an alternative to a failed WAN connection
E. implemented with a point-to-point logical link using a Layer 2 tunnel
Answer: A D
Question 8
Refer to the exhibit.
All primary links are T1 s. The customer wants to have a backup to each remote office from the Headquarters office. Which two types of backup links would be viable solutions? (Choose two)
A. VPDN
B. shadow SVC
C. dial backup routing
D. permanent secondary WAN link
Answer: C D
Question 9
When designing using the Cisco Enterprise Architecture, in which Enterprise Campus layer do the Enterprise Edge and Enterprise WAN modules establish their connection?
A. Campus Core
B. Building Access
C. Enterprise Branch
D. Building Distribution
E. Enterprise Data Center
Answer: A
Question 10
When designing using the Cisco Enterprise Architecture, in which Enterprise Campus layer does the Enterprise Teleworker module establish its connection?
A. Building Core
B. Building Access
C. Enterprise Branch
D. Enterprise Data Center
E. WAN/Internet
Answer: E
Question 11
An organization needs a WAN Transport technology that meets these criteria:
has a low initial cost
provides low-to-medium BW
has medium-to-high latency and jitter
Which technology would you suggest?
A. DSL
B. X.25
C. ISDN
D. wireless
E. analog modem
Answer: A
Question 12
Which two statements best describe the implementation of Overlay VPN connectivity for remote access in the Enterprise Edge WAN module? (Choose two)
A. It must use Layer 2 labels to forward packets
B. It uses dedicated point-to-point links.
C. Bandwidth is provisioned on a site-to-site basis.
D. The ISP actively participates in customer routing.
E. Optimum routing between customer sites requires a full mesh of virtual circuits.
Answer: C E
Question 13
Which codec does Cisco recommend for WAN links?
A. G.711
B. G.723
C. G.728
D. G.729
Answer: D
Is anyone sure of the answer to #6.
Which three types of WAN topologies can be deployed in the Cisco Enterprise Architecture Enterprise Edge WAN module?
A. ring
B. star
C. full mesh
D. core/edge
E. collapsed core
F. partial mesh
Answer: B C F
The ActualTests answer to the same question has a different answer.
It has FULL MESH, COLLAPSED CORE & STAR as the answers to this same question.
Anyone have any thoughts. It looks like Actual Tests may be right.
??
@Skylab. collapsed core must be wrong as it’s not a WAN topology.
collapsed core is when the core and dist layers are performed by one switch
Question 10
When designing using the Cisco Enterprise Architecture, in which Enterprise Campus layer does the Enterprise Teleworker module establish its connection?
A. Building Core
B. Building Access
C. Enterprise Branch
D. Enterprise Data Center
E. WAN/Internet ***
wrong. Wan/internet is not a layer in the enterprise campus. its in thr enterprise edge. so it must be A, as its the only link it has
Hi,
With regards to Q10. The Enterprise Teleworker will establish there connection with the Campus Core. This is because as a permanent remote worker they need full connectivity to the campus and all applications etc. Whereas occasional remote workers do not.
are you sure about q10??? I am get confused now =/
I agree with “above poster”
how about Q5 ?
Which three mechanisms are required to deploy QoS on an IP WAN? (Choose three)
A. traffic classification
B. Call Admission Control
C. queuing and scheduling
D. link efficiency techniques
E. traffic shaping
F. bandwidth provisioning
I would say A, D, and E
Why B is the correct one? As I know traffic classification is a part of QoS configuration.
Reg. Q10- When designing using the Cisco Enterprise Architecture, in which Enterprise Campus layer does the Enterprise Teleworker module establish its connection?
A. Building Core
B. Building Access
C. Enterprise Branch
D. Enterprise Data Center
E. WAN/Internet
Could Option A be correct because teleworker (small office, mobile users, or home users) cannot establish their connection directly to Campus core, they could do only to any of the Ent. edge’s sub- module which are WAN, DMZ/Internet, VPN ,E-commerce. E could have been the answer if the question is “in which Enterprise module” but it is “in which Enterprise Campus layer” , so through Enterprise edge they connect to Core.
Please correct me.
WAN/Internet are modules of Enterprise Edge so it definately answer A in this context.
Rgd Q5
I am going to agree with A,D,E as there is no mention of voice in the IP WAN.
I would say that answer to Q10 should be A.
For Q10 answer should be E :
http://www.cisco.com/en/US/docs/solutions/Enterprise/Security/SAFE_RG/chap7.html
For Q10 answer should be E :
http://www.cisco.com/en/US/docs/solutions/Enterprise/Security/SAFE_RG/chap7.html
but the problem that E is not a Campus Layer but an enterprise edge module…so the answer should be teleworkers connect to the campus core layer through the enterprise wan edge.
@ anon,
Question 10
When designing using the Cisco Enterprise Architecture, in which Enterprise Campus layer does the Enterprise Teleworker module establish its connection?
A. Building Core
B. Building Access
C. Enterprise Branch
D. Enterprise Data Center
E. WAN/Internet ***
Answer is A
Question 5
Which three mechanisms are required to deploy QoS on an IP WAN? (Choose three)
A. traffic classification
B. Call Admission Control
C. queuing and scheduling
D. link efficiency techniques
E. traffic shaping
F. bandwidth provisioning
Answer: A D E
Question 9 is a mess. When a multiple CCIE guy cannot answer it as black and white then the question should not exist any more. Sadly, I believe it still exists in 864. WAN is even part of the edge and connects to core. Edge connects to DC, core and distribution depending on the module we are talking about. If there is any feedback from 864 about this question I would love to hear that.
Question9: I forgot to include that many tests have Building Distribution as the right answer.
For 10 both are wrong. Teleworker terminates at remote/vpn either through isp–> Internet/DMZ or through PSTN sp module. In both cases he is then connected to distribution layer in order to be assigned policies, etc. Look at the main enterprise diagram of the guide book. Perhaps I am going with Internet answer just to align with cisco’s stupidity.
For Q10: assuming that the Cisco Enterprise Architecture Model is correct in the CCDA 640-864 Official Cert Guide (p 48, figure 2-5), the Enterprise Teleworker connects to the Building Distribution layer via PSTN and potentially via ISP by the E-commerce/DMZ/Internet and then down to the Remote Access VPN and to Building Distribution again. The only other alternative is via the E-commerce/DMZ/Internet and directly into the Data Center. The “Enterprise Data Center” and “Building Access” are the only correct terminology used for the Enterprise Campus. Maybe it’s D – Enterprise Data Center if they’re thinking of normal Internet services.
I think E – WAN/Internet makes the most sense if the question wouldn’t have specified Enterprise Campus layer. E would have been the SP Edge which would have otherwise have made sense. The way it’s currently worded though — the best answer would have been Building Distribution but that’s not a choice. The building distribution could have been rolled up into the Campus Core which I might have chosen if it weren’t listed Building Core.
This is simply a badly worded question with bad choices.
Question 10 seems to be worded ambiguously.
“When designing using the Cisco Enterprise Architecture, in which Enterprise Campus layer does the Enterprise Teleworker module establish its connection?”
First and foremost, let’s establish what a “tunnel” really is: essentially a packet from one protocol encapsulated within a datagram of another’s.
The next step would be to define exactly what establishing its connection (in this context) would mean — any takers? On the enterprise teleworkers side, the “tunneling” is generally initiated over a client or an agent. This connection extends from the enterprise teleworkers host, through his router, modem, over the internet [ISP], into the enterprise edget internet connectivity module [EDGE] & Remote Acces/VPN module [EDGE] where the “tunnel” should be terminated meaning the encapsulation is processed and the packet is sent via edge distribution upstream towards the core [ENT CAMPUS] and eventually processed in the data center.
In this model, the “tunnel” is terminated when the encapsulation is processed and the packet is moved towards the core. The core is developed around availability and high performance packet switching, whereas the distribution layers would enforce policy and serve as a routing boundary for the traffic. But since the “tunnel” was already terminated at the Remote Access Device, the remaining packet acts as if was native to the LAN. The packet would need to cross over the core and into the data center so that the upper layers could be processed unless the VPN model was integrated with a directory service for identity.
Let’s stop there and re-read the question:
“When designing using the Cisco Enterprise Architecture, in which Enterprise Campus layer does the Enterprise Teleworker module establish its connection?”
…from the ENTERPRISE ARCHITECTURE (includes CAMPUS, EDGE, WAN, and REMOTE), in which ENTERPRISE CAMPUS (includes ACCESS, DISTRIBUTION, CORE, DC) does the Enterprise TW module establish its connection establish it’s connection.
The connection is established in the core since the tunnel was terminated and pass through the distribution edge. The upper layers will be processed in the datacenter, although the packet found its way in via the core.
A. Building Core (must be the answer, all traffic from the edge goes to the core).
B. Building Access (nope – connection comes from Remote/internet)
C. Enterprise Branch (nope, not an answer)
D. Enterprise Data Center (nope, processes the packet after the connection has been established)
E. WAN/Internet (nope, enterprise edge, not within the enterprise campus
Different deployments would result in different paths, but I think this pretty much settles the debate. Obviously, this is open to discussion since the question is worded ambiguously although the model I presented seems to be rigorous–and accurate.
Q5.
Some corrections on this. You can’t have QoS without the two most basic elements:
A. traffic classification
and
C. queuing and scheduling
So, the answer by DSTUT is wrong. Sorry.
The only options left leave it open to discussion but I feel the best option is:
E. traffic shaping
because it states IP WAN i.e. limited b/w where the SPs usually set CIR/CAR/CBR/PBR and dump your excess so you’d want to shape it and suffer delays on the less important/delay insensitive traffic over loss.
Good luck and thanks DSTUT.
Queuing is a Cisco QoS mechanism but not scheduling. Therefore Link Efficiency, Traffic Classification and Traffic Shaping are QoS mechanisms. A, D, E are the correct answers. Pg 217 in CCDA Cert Guide 4th Edition.
For Question 10, the answer is the core. They are looking for the campus enterprise layer that those two connect to. There is a distribution edge that connects the enterprise edge to the enterprise core. The enterprise edge distribution is not the same as the campus distribution layer.
Nevermind my explanation of question 5. See this link…..
http://www.cisco.com/en/US/docs/voice_ip_comm/cucm/srnd/4x/42nstrct.html#wp1063074
But in the book is shows link efficiency as a QoS mechanism
In the “Implementing Cisco QoS v2.3 in Volume 3 pag 9-74:
OoS policy required on WAN aggregators include queuing,shaping, selective dropping, and link-efficiency policies in the outbound directions of the WAN links. Traffic is assumed to be correctly classified ank marked at Layer3 before WAN aggregator ingress.
Right answer at Q5 are:
C. queuing and scheduling
D. link efficiency techniques
E. traffic shaping
Q1 I think A,C,D. Redundancy does not address the problem of lack of speed. However, a link that is high utilised should be protected.
Q10.
In the Enterprise Architecture model, there is nothing like building core.
We have Campus Core, Building distribution, Building Access and/or Server Farm.
I believe this is a case of a badly worded question. They probably set the question with WAN/Internet as the answer but made a huge error in specifically mentioning Enterprise Campus as the point of reference in the questioning