Computer Networks — Test 8

Correct Answer: B. B. False
Explanation: For a network configuration system to work successfully, several conditions need to be met. Network components are made by different vendors. Even the RMON devices may be from different vendors. Thus, just as in the communication of network management information, standards need to be established for common syntax and semantics for the use of RMON devices.

Correct Answer: A. A. LAN
Explanation: A device that monitors the data packets in a network is called a network monitor or a probe. In a fiber-distributed data interface (FDDI) backbone network with a local Ethernet LAN. There are two remote LANs, one a token-ring LAN and another, an FDDl LAN, connected to the backbone network. Thus a token-ring probe monitors the token-ring LAN.

Correct Answer: A. A. Ethernet
Explanation: RMON1 was initially defined for data link level parameters of Ethernet LAN. It was then extended to token-ring LAN.

Correct Answer: B. B. False
Explanation: To replace commercial tools special tools were developed for the study. The commercial probes were not fast enough to measure the packets traversing an FDDl ring. Hence, a promiscuous mode of counting the packets (function of a probe) was developed to measure traffic on the gateway.

Correct Answer: B. B. Portselect
Explanation: The portSelect group addresses port selection. It is used to define the ports to be monitored in a particular statistics, host, or matrix collection. It contains two tables. The portSelGrpTable controls the set-up of ports and ATM connection selection criteria used on behalf of any collection associated with entries in this table, such as atmHostTable. The portSelTable is then used to control the set-up of selection criteria for a single ATM port.

Correct Answer: A. A. Header
Explanation: The RMON probe is an embedded probe with access to the switch fabric. However, this type of probe measures traffic at the cell header level only.

Correct Answer: B. B. False
Explanation: At the data link sub layer, ATM RMON measures cells instead of packets or frames, and provides cell-based per-host and per-conversation traffic statistics.

Correct Answer: D. D. Protocol directory group
Explanation: The protocol directory group is an inventory of the protocols that the probe can monitor. The capability of the probe can be altered by reconfiguring the protocolDirTable. The protocols range from the data link control layer to the application layer.

Correct Answer: C. C. Data-link
Explanation: RMON1 is covered by RFC 1757 for Ethernet LAN and RFC 1513. RMON in general and RMON1 specifically, performs numerous functions at the data link layer. Hence it can be said that RMON1 majorly dealt with data that associated with data-link layer of the OSI model.

Correct Answer: B. B. Application-layer matrix
Explanation: The application layer functions are grouped into two groups, the application-layer host group and the application layer matrix group. They both calculate traffic by protocol units and use their respective control tables in the network-layer host group and the network-layer matrix group. The application-layer matrix group can also generate a report of the top N protocol conversations.