1. POSTECH DP&NM Lab 1 Remote Network Monitoring (RMON)

2. POSTECH DP&NM Lab 2 Table of Contents Basic Concepts RMON Goals RMON MIB Groups RMON2

3. POSTECH DP&NM Lab 3 RMON Basic Concepts Extends the SNMP functionality without changing the protocol Allows the monitoring of remote networks (internetwork management) MAC-layer (layer 2 in OSI) monitoring Defines a Remote MONitoring (RMON) MIB that supplements MIB-II –with MIB-II, the manager can obtain information on individual devices only –with RMON MIB, the manager can obtain information on the LAN as a whole called network monitors, analyzers or probes

4. POSTECH DP&NM Lab 4 RMON RFCs

5. POSTECH DP&NM Lab 5 RMON Goals Monitoring subnetwork-wide behavior Reducing the burden on agents and managers Continuous off-line monitoring in the presence of failures (in network or manager) Proactive monitoring –perform some of the manager functions (e.g., diagnostics) Problem detection and reporting Provide value-added (analyzed) data Support multiple managers

6. POSTECH DP&NM Lab 6 Example Configuration for Remote Monitoring Bridge Router FDDI backbone Token Ring LAN Router with RMON probe Management console with RMON probe Central Site Local management console with RMON probe PC with RMON probe PC with RMON probe Ethernet

7. POSTECH DP&NM Lab 7 Example of RMON probe with two interfaces agent a agent b RMON probe agent c agent e agent d Interface 1 Interface 2 Subnetwork X Subnetwork Y

8. POSTECH DP&NM Lab 8 Control of Remote Monitors RMON MIB contains features that support extensive control from NMS –Configuration control –Action Invocation RMON MIB is organized into a number of functional groups Each group may contain one or more control tables and one or more data tables Control table (typically read-write) contains parameters that describe the data in a data table (typically read-only)

9. POSTECH DP&NM Lab 9 RMON MIB rmon (mib-2 16) statistics (1) history (2) alarm (3) host (4) hostTopN (5) matrix (6) filter (7) capture (8) event (9) tokenRing (10)

10. POSTECH DP&NM Lab 10 RMON MIB Groups 1. statistics: maintains MAC-level utilization and error stats 2. history: records periodic statistical samples from the stats group 3. alarm: allows NMS to set sampling interval & alarm threshold 4. host: contains counters for traffic from hosts on the subnetwork 5. hostTopN: contains sorted host stats that top a list based on some parameter in the host table 6. matrix: shows utilization and error stats in matrix for host pairs 7. filter: allows the monitor to observe packets that match a filter 8. capture: specifies how data is sent to NMS 9. event: specifies events to be generated by the RMON probe 10. tokenRing: maintains stats & config info for token ring subnet

11. POSTECH DP&NM Lab 11 RMON MIB2 RMON MIB monitors MAC-level subnet traffic RMON MIB2 can monitor traffic of packets at layers 3 to 7 of the OSI Reference Model Provides Network-layer Visibility –can distinguish between local LAN and remote LAN traffic Provides Application-layer Visibility –can analyze traffic to and from hosts for particular applications –can determine which applications are putting the load on the net RMON MIB2 is basically an extension of RMON MIB

12. POSTECH DP&NM Lab 12 RMON MIB2 rmon (mib-2 16) statistics (1) history (2) alarm (3) host (4) hostTopN (5) matrix (6) filter (7) capture (8) event (9) tokenRing (10)probeConfig (19) usrHistory (18) alMatrix (17) alHost (16) nlMatrix (15) nlHost (14) addressMap (13) protocolDist (12) protocolDir (11) RMON 1 RMON 2

13. POSTECH DP&NM Lab 13 RMON MIB2 Groups 11. protocolDir: a master directory of all of the protocols that the probe can interpret 12. protocolDist: aggregate stats on the amount of traffic generated by each protocol, per LAN segment 13. addressMap: contains MAC and port addresses of the devices 14. nlHost: network layer traffic stats per host 15. nlMatrix: network layer traffic stats per pairs of hosts 16. alHost: application layer traffic stats per host 17. alMatrix: application layer traffic stats per pairs of hosts 18. userHistory: periodically samples and logs user-defined data 19. probeConfig: defines standard configuration parameters for RMON probes

14. POSTECH DP&NM Lab 14 Summary RMON extends the SNMP functionality without changing the protocol RMON can monitor information on a whole subnetwork RMON is used extensively in analyzing network traffic for problem detection and network planning RMON2 allows monitoring of traffic at layers 3 to 7 in the OSI Model RMON2 can be used to analyze network traffic more accurately even to the application level Read Chapters 8, 9 and 10

15. POSTECH DP&NM Lab Lab activity 15 RMON GroupFunctionElements