H3C Technologies H3C SR8800 - Manual (Page 145)

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Configuring NetStream
NOTE:
In this documentation, SPC cards refer to the cards prefixed with SPC, for example, SPC-GT48L. SPE cards
refer to the cards prefixed with SPE, for example, SPE-1020-E-II. NAM cards refer to the cards prefixed
with IM-NAM, for example, IM-NAM-II.
NetStream overview
Conventional traffic statistics collection methods, like SNMP and port mirroring, cannot provide precise
network management because of inflexible statistical methods or high cost (dedicated servers are
required). This calls for a new technology to collect traffic statistics.
NetStream provides statistics on network traffic flows and can be deployed on access, distribution, and
core layers.
The NetStream technology implements the following features:
• Accounting and billing—NetStream provides fine-gained data about the network usage based on
the resources such as lines, bandwidth, and time periods. The Internet service providers (ISPs) can
use the data for billing based on time period, bandwidth usage, application usage, and quality of
service (QoS). The enterprise customers can use this information for department chargeback or cost
allocation.
• Network planning—NetStream data provides key information, for example the autonomous system
(AS) traffic information, for optimizing the network design and planning. This helps maximize the
network performance and reliability when minimizing the network operation cost.
• Network monitoring—Configured on the Internet interface, NetStream allows for traffic and
bandwidth utilization monitoring in real time. Based on this, administrators can understand how the
network is used and where the bottleneck is, better planning the resource allocation.
• User monitoring and analysis—The NetStream data provides detailed information about network
applications and resources. This information helps network administrators efficiently plan and
allocate network resources, and guarantee network security.
NetStream basic concepts
Flow
NetStream is an accounting technology to provide statistics on a per-flow basis. An IPv4 flow is defined
by the 7-tuple elements: destination IP address, source IP address, destination port number, source port
number, protocol number, type of service (ToS), and inbound or outbound interface. The 7-tuple elements
define a unique flow.