An efficient transmission for large MIB tables in polling-based SNMP

Abstract

Presently, the composition of networks has not only been very complicated but also the total number of nodes that compose a network has increased greatly. Therefore, efficient network management is becoming vital. SNMP (Simple Network Management Protocol) is a management protocol that is widely used standard for remote management of devices in IP networks. In network management using SNMP, a central NMS (Network Management System) requires management information in MIB (Management Information Base) by polling repeatedly to embedded SNMP agents in remote devices for monitoring the network resources. Especially, when NMS required the MIB table (as versus MIB scalars) to SNMP agent, it raises bulk data transfer (e.g. TcpCorinectionTable, IproutingTable). Furthermore, the contents of the MIB table changed frequently. As the result, NMS polls agents in shorter intervals in order to get the most recent NUB table, leading to bulk transfers between the NMS and its agents. The bulk transfer between the NMS and SNMP agents raises several problems. It is not only limits the number of network nodes which the NMS is able to manages but also makes the state of the network difficult to understand in real-time, causing transmission latency. To resolve these problems, this paper propose a GetModify mechanism which is a tool that substantially reduces bulk transfers of dynamic, large MIB tables by transferring changed data only during polling intervals from SNMP agents. This mechanism enables managers to monitor networks efficiently with less network overhead and latency.