Bgp — Test 1

Correct Answer: B. B. Stub, transit and multi-homed
Explanation: Transit is the only AS that allows data traffic to go through it. Stub and multi-homed will have connections with single and multiple AS respectively and do not allow themselves to be a service provider to allow traffic across them.

Correct Answer: C. C. To interchange the routing information
Explanation: Usually BGP uses TCP services while establishing the sessions between BGP routers. A session is more like a connecting link to exchange only the information of routing and these BGP sessions are persistent.

Correct Answer: B. B. E-bgp session
Explanation: E-BGP stands for external border gateway protocol and internal BGP sessions are used only within the AS. Unlike I-BGP, external BGP sessions are used to share and retrieve the routing information of the routers which belongs to different AS.

Correct Answer: A. A. Reduced traffic
Explanation: The traffic that autonomous systems get when they do peering is low compared to the traffic that they get when they use provider. And also, the provider lets its other customers to know the path of these ASs and it leads to more traffic to these ASs.

Correct Answer: B. B. Router keeps track of the path
Explanation: Basically, intra-domain routing maintains the table for each destination with least cost or distance. But in BGP, metric is policy, so every router keeps track of the path like next hop and AS path. This path vector protocol avoids looping using path tracking.

Correct Answer: D. D. When autonomous system is transit as
Explanation: Border gateway protocol is more useful when the AS is transit because BGP is capable of inter-domain routing. So, it can handle the data traffic well when the ASs are transit.

Correct Answer: C. C. List of attributes
Explanation: When traffic is sent from one network to another network, then every router within the route checks the path. This path contains not only the number of AS but also contains attributes that give information about the path such as next_hop.

Correct Answer: C. C. Well-known and optional
Explanation: Well known and optional are two major categories of attributes. Mandatory and discretionary are categories of well-known attribute. Optional attribute also has two categories called transitive and non-transitive.

Correct Answer: D. D. Next_as
Explanation: Origin defines the source of the packet and As_path defines the sequence of ASs that a packet follows and Next_hop defines about the next router that a packet is going to visit.

Correct Answer: B. B. False
Explanation: IGP protocols are intra-domain protocols, whereas BGP is an inter-domain protocol. It works among the autonomous systems which are owned by individual administrations rather than working within the autonomous system.