Sflow Sampling Unit; Sflow Agent Unit; Sflow Collector - Zte ZXR10 5900 Series User Manual

ZXR10 5900/5200 Series User Manual (Ethernet Switching Volume)

SFlow Sampling Unit

SFlow sampling unit implements on router, switch and other net-
work devices that need monitor. In the network system of router,
switch and so on, generally, implement packet sampling function
by network processor or ASIC chip.
SFlow sampling module mainly sample the packet according to
the user demands, meanwhile send the statistic information in
relevant packet forwarding procedure. In this process, the orig-
inal packet is totally not affected and this simple process mode
doesn't affect device original performance of processing packet.
The mechanism is simple and easy for processing and implemen-
tation on hardware and software.
Firstly, configure a sampling rate for sampling interface, which
can be a fixed value such as sampling a packet every N pack-
ets , or dynamic sampling rate such as deciding the current sam-
pling rate dynamically according to current port working speed,
system resource utility ratio and other information. When setting
sampling rate, sFlow works normally. For the packet that need
to be collected, system copies the packet or only copies the max-
imum packet length that sFlow Agent needs, sends the copy of
the packet, source port and destination port of the packet, the
current total packet counter value, sampling packet counter value
and other information to sFlow agent module for processing. After
sampling, packet are forwarded according to normal packet for-
warding workflow.

SFlow Agent Unit

The main function of SFlow Agent is to analyze sampling packet
, send encapsulated sFlow packet according to protocol to sFlow
collector device, meanwhile read the statistic information on the
interface and send them to sFlow collector device.
The location of sFlow agent module can be in network device itself
or outside of device. For most network devices supporting sFlow,
sFlow agent unit is integrated into management module of net-
work device. SFlow agent unit runs on a part of device network
management software module. It integrates interface count infor-
mation and sampling packet information into sFlow management
packet which is sent to sFlow collector.

SFlow Collector

SFlow Collector is the network device that sFlow manage, monitor,
collect and analyze. It is responsible for storing packet sended
from each sFlow Agent on the network and then analyzing to give
device traffic and various analysis report of service. Meanwhile,
some collector software that have MIB function can configure sFlow
agent.
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