Carrier Access Access Bank II SNMP - Manual (Page 148)

SNMP Management
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objects with predefined MIB data structures. The Access Bank II/SNMP uses the Bellcore ® standard
MIB for T1 interfaces.
Manager operations include simple “get” and “set” commands to retrieve and update MIB data in the
Agent. Normally, the Manager polls the Agent periodically to check traffic statistics. However, the
Manager can also set thresholds for traps. Traps specify network events and conditions for which the
Agent automatically sends a Telnet alarm message with trap data back to the Manager.
The Access Bank II SNMP Agent’s principle benefits are the proactive management of V.35 and
DSX-1 alarms, performance statistics, and line tests.
14.3.3 Protocols
The Manager and Agent are software applications. They communicate with each other through sev-
eral protocol layers (Figure 14-2) that are normally transparent to the user. The Access Bank II/
SNMP uses Ethernet as the physical link between the Manager and Agent. The Ethernet data can, in
turn, be carried over either of the T1 lines within a V.35 user data segment.
SNMP is an application-level protocol intended to work with the User Datagram Protocol (UDP) and
Internet Protocol (IP) suite, which includes BootP, Internet Control Message Protocol (ICMP),
Address Resolution Protocol (ARP), and Reverse ARP (RARP). The advantage of UDP is that each
message is independent; no network connections are maintained between the Manager and Agent.
Figure 14-2: Protocol Hierarchy Used In Access Bank II SNMP
Telnet
IP
SNMP
TCP UDP
Ethernet
ICMP BootP ARP RARP
Manager Agent (many paths are possible)