Multi-Stream Analysis
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port A (loop) mode is available for Port A only, while the Match port B (loop) is
available for Port B only.
Current filtering configuration is always available from the summary screen. In this
screen use the Port A and Port B contextual buttons to choose between Port A or
Port B filters and the Filters check box to display filtering configuration.
6.2.Configuring Filters
To allow the filter to accept and process frames, a correct filtering criteria must be
configured before being used. To configure the correct filtering criteria two decisions
must be taken. First, it is necessary to know which frame fields are going to be matched
and after that, which are the value or values to be matched. The first decision involves
choosing whether the filtering is going to be done at MAC, IP or transport layer and
which specific frame field or fields are going to be used for filtering (MAC addresses, IP
addresses, Ethertype field, protocol or any other). The second is carried out by
configuring the field value and sometimes a mask. The mask selects which field bits
are taken into account when a frame is matched. Matching masks are not related to IP
subnet masks even if they can be applied to IP addresses. Specifically, the binary
representation of a matching mask does not need to be a sequence of ‘1’ followed by
a sequence of ‘0’ like IP network masks are.
The generic procedure to configure one or several matching criteria in the test unit is
the following:
1. From the Home panel, go to CONFIG,
The test port settings panel is displayed.
2. Select either Port A or Port B to enter in the port specific configuration.
3. Enter in Filters
4. Select one of the filtering menus labelled as Filter A1, Filter A2, etc. (or Filter B1,
Filter B2, etc. in Port B).
All configuration items related with the filter configuration are displayed.
5. Configure Filter mode to one of Block, Custom or Match port A / Match port B,
Match port A (loop) / Match port B (loop) values
Block, Match port A / Match port B and Match port A (loop) / Match port B (loop)
have fixed filtering rules but if you choose custom, different types of filtering rules
are enabled for that filter: Fixed offset, MAC, C-VLAN, S-VLAN, IPv4, IPv6, UDP.
6. If you have configured Custom filtering, select the matching rule.
7. For custom filters, choose a matching field and configure the matching mode for
this field. Most of the matching fields have at least two matching modes. The
Equal mode selects frames matching the configured value or values for the field
and Ignore does not match any frame by the current field. Other matching modes
may be available in specific fields.
8. Configure the field value to be matched by the filter.
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