SNMP - Ingenico

SNMP
SIMPLE NETWORK MANAGEMENT PROTOCOL
SNMP (Simple Network Management Protocol) is a set of protocols for monitoring
widely distributed networks. The first versions of SNMP were developed as early
as the 1980s, and SNMP is now widely adopted in the IT industry. This functionality
is based on the manager/agent model, meaning that a network manager can
access the data stored in remote devices. It is particularly well suited for network
alarm monitoring and making networks more reliable. The main application
today is monitoring routers to retrieve network status information.
This protocol is only applicable over TCP/IP networks, as it is based on this protocol
stack. The small number of commands used and the independence between
agents and managers make SNMP a simple, robust protocol. These two factors
have contributed strongly to its widespread use.

HOW SNMP WORKS 3
INGENICO’S SNMP IMPLEMENTATION 3
EXAMPLE USES 5
DYNAMIC STATISTICS 5
PREVENTIVE DIAGNOSTICS 5
DYNAMIC TERMINAL MANAGEMENT 5
CONCLUSION 5

SNMP
HOW SNMP WORKS
SNMP is based on the manager/agent model. This
model allows SNMP managers to remotely access
information stored by agents. The manager and
agent use a Management Information Base (MIB)
and a short set of commands to exchange
information, making the SNMP protocol light and
easy to implement.
HUMAN
NETWORK
MANAGER
MANAGEMENT
SYSTEM
MANAGER
Database
Figure 1. Basic SNMP model
NETWORK
PROTOCOL
MESSAGES
TARGET
AGENT
Managed
Objects
SNMP uses only five basic messages to manage
communication between the manager and agent.
The first two messages (Get, GetNext) allow the
manager to request information for a specific object
or list of objects. The agent then replies through
a GetResponse message that contains either the
requested information or an error code (the Third
message).
When the manager wants to obtain the value
of an object, it creates a Get message that includes
the Object Identifier (OID) for each object of interest,
and sends this message to the agent. The agent
then checks whether the OIDs are included in its
base. If they are, it replies with the objects’ value;
if they are not, it sends an error code.
The fourth message (Set) allows the manager
to request a change in the value of a specific
variable. To reply, the agent uses the GetResponse
message to either provide the information or give
an error code.
The final message (Trap) allows the agent to
inform the manager of a significant event.
Most of the messages are issued only by the
SNMP manager. The Trap message is the only one
initiated by the agent, and is typically used to notify
the manager of an alarm condition – before the
manager queries that object.
When the agent detects that one of its objects
listed for SNMP has been modified, it generates
a Trap message to inform the manager. This allows
the manager to deal with the new value more
proactively, as opposed to waiting for the next time
that particular object is queried.
SNMP’S ADVANTAGES
• It is LAN/WAN based. Because SNMP allows
data transfer over existing LAN/WAN networks, it
significantly cuts deployment and operating costs.
• It is an open standard. SNMP is available
free-of-charge, is documented extensively, and is
supported by most telecoms equipment providers.
• It is expandable. Although SNMP is light and simple,
it can be expanded to support a wide variety of
connected devices.
• It is platform-independent. An SNMP manager can
be configured through the Management Information
Base (MIB) to enable data transfer with any device
supporting SNMP (e.g., combined IT & POS
environments).
INGENICO’S SNMP IMPLEMENTATION
SNMP has been implemented by Ingenico across
its product lines, in order to support customers in
remote POS administration. This implementation
was carried out through an LNET library upgrade,
the addition of an SNMP agent in the new
LSNMP library, and an OS upgrade. Ingenico’s
implementation is fully compliant with the standard
and is based on version 2.c SNMP.
INGENICO 2007
3.

The SNMP module is launched automatically
when a terminal is booted, and offers immediate
functionality to the agent (the SNMP function
can be deactivated if needed). This protocol can
be used by any terminal with a TCP/IP stack:
Ethernet, WiFi, Bluetooth, GPRS, CDMA, etc.
SNMP can be used to retrieve statistical data
about POS terminals that is stored on a central
network manager. Three types of data can be
obtained:
• OS data;
• TCP/IP stack information;
• Application data.
The OS data include:
• Number of terminal boots;
• Number of pixel lines printed;
• Number of magnetic cards swiped
(and with at least one good track read);
• Number of smart cards inserted
(asynchronous or synchronous);
• Number of modem calls
(and successful modem calls);
• Number of keys pressed.
This data can be activated on all Ingenico
terminals. The schematic below illustrates how
OS data is retrieved using SNMP.
OS
Application
LSNMP
agent
�
TCP/IP
stack
OS data
INTERNET
Figure 2. SNMP retrieval of OS data
LSNMP
manager
TCP/IP stack information provides details on
the amount of data sent and received, the protocol
used, the transfer success rate, etc. Applications
can also generate specific counters for tracking
targeted indicators.
All this information is stored by the SNMP agent
to be presented to the remote manager. However,
an application can specify that its information
be non-public, in which case the agent will not
send it to the manager.
The network manager collects data from
the terminal through regular contact at defined time
intervals, and can reset some counters to enable
fully automated management. For example, the
number of Visa or MasterCard cards used on the
terminal can be counted over a set time period, then
reset to zero at the start of the next time period.
The schematic below illustrates the SNMP
agent response when OS, TCP/IP, and application
objects are declared.
Application
statistics
OS
Application
LSNMP
agent
� �
�
TCP/IP
stack
TCP/IP
stack
information
OS data
INTERNET
LSNMP
manager
Figure 3. SNMP functionality with OS, TCP/IP, and application objects
Ingenico has also implemented the Trap message
discussed earlier, which is used by the terminal
to notify the network manager that an object has
been modified. The manager can thus check the
object immediately to view the updated information.
INGENICO 2007
4.

The Trap message is useful for tracking statistics
like paper status or reboot sequence, and allows
real-time control of a group of terminals without
the need for a field technician. Alerts of object
modifications are sent automatically by the
application to one or more network managers.
Another benefit of the Trap message is that it
can work the other way round. A network manager
can set a new value in an application's object,
which will then force the application to launch
an OS update or data collection sequence.
EXAMPLE USES
SNMP is now a common technology and increasingly
available on network servers. Thanks to SNMP
standards, Ingenico customers can manage their
terminals easily through a single application
on a server. Ingenico customers can access SNMP
terminals from any structure supporting TCP/IP,
so that implementation can be a simple extension
of an existing IT administration application
or a bank or third-party server.
Moreover, implementing SNMP facilitates the
administration of a group of Ingenico terminals.
More specifically, it can be used for the following:
DYNAMIC STATISTICS
• Network performance based on TCP/IP data
• Transaction volume data
• Payment statistics, so that banks can adapt their
services to retailers’ needs
(e.g., specific functions for low payments, a new
telecom subscription offer, etc.)
PREVENTIVE DIAGNOSTICS
• Dynamic trouble-shooting
• Field preventive maintenance
(e.g., the early detection of an increase in modem
call failure or magnetic strip reading)
DYNAMIC TERMINAL MANAGEMENT
• Modifications to data transfer connections
between agents and servers
• Automatic maintenance procedure generation
(i.e., if a server detects a possible incompatibility
with an application or updated communication
parameters, it can automatically request that
the agent launch an application upgrade through
the SNMP manager)
• Terminal queries for parameter and/or
configuration upgrades
CONCLUSION
By implementing the SNMP technology, Ingenico
has again demonstrated its desire to provide
customers with the best-suited and most
cost-effective solutions available. This widespread,
light protocol is easy to deploy, and allows Ingenico
terminals to be integrated into an existing SNMP
environment if needed.
Groupe Ingenico
192, avenue Charles de Gaulle
92200 Neuilly-sur-Seine - France
Tel : +33 (0)1 46 25 82 00
Fax : +33 (0)1 47 72 56 95
www.ingenico.com 02-2007