CCNA 4 v6.0 (Connecting Networks v6) Chapter 3: Branch Connections: Check Your Understanding Questions Answers
1. Which technology provides a secure connection between a SOHO and the headquarters office?
- PPPoE
- QoS
- VPN
- WiMax
Explanation: The term SOHO refers to small offices and home offices from which many telecommuters work. VPN is a virtual private network and provides a secure connection between the SOHO and the headquarters office. PPPoE is a point-to-point technology over Ethernet, and WiMax is a broadband wireless technology.
2. Which two network components does a teleworker require to connect remotely and securely from home to the corporate network? (Choose two.)
- Authentication server
- Broadband Internet connection
- VPN client software or VPN-enabled router
- Multifunction security appliance
- VPN server or concentrator
Explanation: To enable the secure management of teleworkers who connect to the corporate network via VPN, a VPN server or concentrator, an authentication server, and multifunction security appliances are necessary components at the corporate end. They are not client requirements.
3. What advantage does DSL have compared to cable technology?
- DSL has no distance limitations.
- DSL is faster.
- DSL is not a shared medium.
- DSL upload and download speeds are always the same.
Explanation: Unlike cable technology, DSL is not a shared medium. Each user has a separate connection to the DSLAM. Different varieties of DSL provide both symmetrical and asymmetrical connections. Generally, the local loop is limited to 3.39 miles using DSL.
4. Which medium is used for delivering data via DSL technology through PSTN?
- Copper
- Fiber
- Radio frequency
- Wireless
Explanation: A digital subscriber line (DSL) delivers high-speed connections over existing copper wires (PSTN).
5. What technology provides service providers the capability to use authentication, accounting, and link management features to customers over Ethernet networks?
- DSL
- ISDN
- PPPoE
- QoS
Explanation: PPPoE provides the authentication, accounting, and link management features inherent with PPP. QoS refers to the capability to provide better service to selected network traffic. DSL is a broadband technology, and ISDN is a dialup technology.
6. Why is the MTU for a PPPoE DSL configuration reduced from 1500 bytes to 1492?
- To accommodate the PPPoE headers
- To enable CHAP authentication
- To establish a secure tunnel with less overhead?
- To reduce congestion on the DSL link
Explanation: The default maximum data field of an Ethernet frame is 1500 bytes. However, in PPPoE the Ethernet frame payload includes a PPP frame that has also has a header. This reduces the available data MTU to 1492 bytes.
7. What are two characteristics of a PPPoE configuration on a Cisco customer router? (Choose two.)
- An MTU size of 1492 bytes is configured on the Ethernet interface.
- The customer router CHAP username and password are independent of what is configured on the ISP router.
- The dialer pool command is applied to the Ethernet interface to link it to the dialer interface.
- The Ethernet interface does not have an IP address.
- The PPP configuration is on the dialer interface.
Explanation: PPP, CHAP, an IP address, the dialer pool number, and the MTU size are all configured on the dialer interface. The customer router CHAP username and password must match what is configured the ISP router. The pppoe-client command, not the dialer pool command, is applied to the Ethernet interface to link it to the dialer interface.
8. When PPPoE is configured on a customer router, which two commands must have the same value for the configuration to work? (Choose two.)
- dialer pool 2
- interface dialer 2
- interface gigabitethernet 0/2
- ppp chap hostname 2
- ppp chap password 2
- pppoe-client dial-pool-number 2
Explanation: The dialer pool number configured on both the dialer and Ethernet interfaces must match. The interface numbers and the username and the password do not have to match.
9. A network design engineer is planning the implementation of a cost-effective method to interconnect multiple networks securely over the Internet. Which type of technology is required?
- A dedicated ISP
- A GRE IP tunnel
- A leased line
- A VPN gateway
Explanation: A GRE IP tunnel does not provide authentication or security. A leased line is not cost effective when compared to using high-speed broadband technology with VPNs. A dedicated ISP is not required when utilizing VPNs between multiple sites.
10. Which statement describes a feature of site-to-site VPNs?
- Individual hosts can enable and disable the VPN connection.
- Internal hosts send normal, unencapsulated packets.
- The VPN connection is not statically defined.
- VPN client software is installed on each host.
Explanation: Site-to-site VPNs are statically defined VPN connections between two sites that use VPN gateways. The internal hosts do not require VPN client software and send normal, unencapsulated packets onto the network where they are encapsulated by the VPN gateway.
11. Which remote-access implementation scenario will support the use of Generic Routing Encapsulation tunneling?
- A branch office that connects securely to a central site
- A central site that connects to a SOHO site without encryption
- A mobile user who connects to a router at a central site
- A mobile user who connects to a SOHO site
Explanation: The GRE tunneling protocol is used for site-to-site VPNs, not for remote-access VPNs for mobile users. GRE alone does not provide any encryption, so the traffic is not secure between the endpoints.
12. Which two statements are key characteristics of BGP? (Choose two.)
- It provides interdomain routing between autonomous systems.
- It is an advanced distance vector routing protocol.
- It uses cost as its metric.
- It is a link-state routing protocol.
- It uses bandwidth and delay as its metric.
- It is a policy-based routing protocol.
Explanation: BGP is the only interdomain routing protocol that routes between autonomous systems. It does not use cost or hop count as its metric but instead is policy-based, which means it makes its routing decision based on configurable policies.
13. Which BGP routers will become peers and share routing information?
- All BGP routers in the same domain share routing information by default
- BGP routers that are configured with the same network command
- BGP routers that are configured with the same peer command
- BGP routers that are identified with the neighbor command
Explanation: BGP routers can establish adjacencies only with other BGP routers identified by the neighbor router configuration command.
14. Which of the following BGP statements is true?
- BGP is an IGP used to exchange routing information with another AS.
- BGP updates are encapsulated using TCP port 179.
- Every AS is assigned a unique 160-bit AS number (ASN).
- Use BGP when there is a single connection to the Internet or another AS.
Explanation: BGP updates are encapsulated over TCP on port 179. In BGP, every AS is assigned a unique 16-bit or 32-bit AS number (ASN). BGP is an Exterior Gateway Protocol (EGP) used for the exchange of routing information between autonomous systems. BGP should not be used when there is a single connection to the Internet or another AS.
15. Assume R1 is in AS 5000 and wants to establish an eBGP peer relationship with another router. Which of the following commands would correctly configure an eBGP relationship?
- R1(config-router)# neighbor 209.165.201.1 remote-as 5000
- R1(config-router)# neighbor 209.165.201.1 remote-as 10000
- R1(config-router)# peer 209.165.201.1 remote-as 5000
- R1(config-router)# peer 209.165.201.1 remote-as 10000
Explanation: An External BGP (eBGP) relationship configured between two routers in different autonomous systems uses this neighbor router configuration command.