# wireshark-filter

## NAME



           wireshark-filter - Wireshark display filter syntax and reference
    


## SYNOPSIS



           **wireshark**[other options] [ **-Y** "display filter expression" |
           **--display-filter** "display filter expression" ]
    
           **tshark**[other options] [ **-Y** "display filter expression" |
           **--display-filter** "display filter expression" ]
    


## DESCRIPTION



           **Wireshark** and **TShark** share a powerful filter engine that helps
           remove the noise from a packet trace and lets you see only the
           packets that interest you. If a packet meets the requirements
           expressed in your filter, then it is displayed in the list of
           packets. Display filters let you compare the fields within a
           protocol against a specific value, compare fields against fields,
           and check the existence of specified fields or protocols.
    
           Filters are also used by other features such as statistics
           generation and packet list colorization (the latter is only
           available to **Wireshark**). This manual page describes their syntax.
           A comprehensive reference of filter fields can be found within
           Wireshark and in the display filter reference at
           https://www.wireshark.org/docs/dfref/.
    


## FILTER SYNTAX



       **Check whether a field or protocol exists**
           The simplest filter allows you to check for the existence of a
           protocol or field. If you want to see all packets which contain
           the IP protocol, the filter would be "ip" (without the quotation
           marks). To see all packets that contain a Token-Ring RIF field,
           use "tr.rif".
    
           Whenever a protocol or field appears as the argument of a function
           in a filter, an exists operator for that protocol or field
           implicitly appears.
    
       **Values and operators**
           Each field has a value, and that value can be used in operations
           with comparable values (which may be literals, other fields, or
           function results). The value of a field is not necessarily what
           appears in the **Wireshark** display or **TShark** output. For example, a
           protocol is semantically equivalent to the sequence of bytes that
           it spans, not its displayed text in the protocol tree.
    
       **Comparison operators**
           The comparison operators can be expressed either through
           English-like abbreviations or through C-like symbols:
    
               eq, ==    Equal
               ne, !=    Not Equal
               gt, >     Greater Than
               lt, <     Less Than
               ge, >=    Greater than or Equal to
               le, <=    Less than or Equal to
    
           The ordering depends on the value type in the usual way (e.g.,
           lexicographic for strings and arithmetic for integers.) A field
           may appear more than once in a given frame. In that case equality
           can be strict (all fields must match the condition) or not (any
           field must match the condition). The inequality is the logical
           negation of equality. The following table contains all equality
           operators, their aliases and meaning:
    
               eq, any_eq, ==    Any field must be equal
               ne, all_ne, !=    All fields must be not equal
                   all_eq, ===   All fields must be equal
                   any_ne, !==   Any fields must be not equal
    
           The operators "any" or "all" can be used with any comparison
           operator to make the test match any or all fields:
    
               all tcp.port > 1024
    
               any ip.addr != 1.1.1.1
    
           The "any" and "all" modifiers take precedence over comparison
           operators such as "===" and "any_eq".
    
       **Search and match operators**
           Additional operators exist expressed only in English, not C-like
           syntax:
    
               contains     Does the protocol, field or slice contain a value
               matches, ~   Does the string match the given case-insensitive
                            Perl-compatible regular expression
    
           The "contains" operator allows a filter to search for a sequence
           of characters, expressed as a string, or bytes, expressed as a
           byte array. The type of the left hand side of the "contains"
           operator must be comparable to that of the right hand side after
           any implicit or explicit conversions.
    
           For example, to search for a given HTTP URL in a capture, the
           following filter can be used:
    
               http contains "https://www.wireshark.org"
    
           The "contains" operator cannot be used on atomic fields, such as
           numbers or IP addresses.
    
           The "matches" or "~" operator allows a filter to apply to a
           specified Perl-compatible regular expression (PCRE2). The regular
           expression must be a double quoted string. The left hand side of
           the "matches" operator must be a string, which can be a
           non-stringlike field implicitly or explicitly converted to a
           string. Matches are case-insensitive by default. For example, to
           search for a given WAP WSP User-Agent, you can write:
    
               wsp.header.user_agent matches "cldc"
    
           This would match "cldc", "CLDC", "cLdC" or any other combination
           of upper and lower case letters.
    
           You can force case sensitivity using
    
               wsp.header.user_agent matches "(?-i)cldc"
    
           This is an example of PCRE2’s **(?** option**)** construct. **(?-i)** performs
           a case-sensitive pattern match but other options can be specified
           as well. More information can be found in the
           pcre2pattern(3)|https://www.pcre.org/current/doc/html/pcre2pattern.html
           man page.
    
       **Functions**
           The filter language has the following functions:
    
               upper(string-field) - converts a string field to uppercase
               lower(string-field) - converts a string field to lowercase
               len(field)          - returns the byte length of a string or bytes field
               count(field)        - returns the number of field occurrences in a frame
               string(field)       - converts a non-string field to string
               vals(field)         - converts a field value to its value string
               dec(field)          - converts an unsigned integer to a decimal string
               hex(field)          - converts an unsigned integer to a hexadecimal string
               float(field)        - converts a field to single precision floating point
               double(field)       - converts a field to double precision floating point
               max(f1,...,fn)      - return the maximum value
               min(f1,...,fn)      - return the minimum value
               abs(field)          - return the absolute value of numeric fields
    
           upper() and lower() are useful for performing case-insensitive
           string comparisons. For example:
    
               upper(ncp.nds_stream_name) contains "MACRO"
               lower(mount.dump.hostname) == "angel"
    
           string() converts a field value to a string, suitable for use with
           operators like "matches" or "contains". Integer fields are
           converted to their decimal representation. It can be used with
           IP/Ethernet addresses (as well as others), but not with string or
           byte fields. For example:
    
               string(frame.number) matches "[13579]$"
    
           gives you all the odd packets. Note that the "matches" operator
           implicitly converts types of their value string representation; to
           match against the decimal representation of an integer field use
           string().
    
           vals() converts an integer or boolean field value to a string
           using the field’s associated value string, if it has one. This
           produces strings similar to those seen in custom columns. The
           resultant string can also be used with other operators. E.g.:
    
               vals(pfcp.msg_type) contains "Request"
    
           would match all packets which have a PFCP request, even if that
           request is not matched with a response.
    
           dec() and hex() convert unsigned integer fields to decimal or
           hexadecimal representation. Currently dec() and string() give same
           result for an unsigned integer, but it is possible that in the
           future string() will use the native base of the field.
    
           max() and min() take any number of arguments and returns one
           value, respectively the largest/smallest. The arguments must all
           have the same type.
    
           There is also a set of functions to test IP addresses:
    
               ip_special_name(ip)       - Returns the IP special-purpose block name as a string
               ip_special_mask(ip)       - Returns the IP special-purpose block flags as a mask. The bits are:
                                               4 3 2 1 0
                                               ---------
                                               S D F G R
                                           S = Source, D = Destination, F = Forwardable, G = Globally-reachable, R = Reserved-by-protocol
    
               ip_linklocal(ip)          - true if the IPv4 or IPv6 address is link-local
               ip_multicast(ip)          - true if the IPv4 or IPv6 address is multicast
               ip_rfc1918(ipv4)          - true if the IPv4 address is private-use (from the allocation in RFC 1918)
               ip_ula(ipv6)              - true if the IPv6 address is unique-local (ULA) as in RFC 4193
    
       **Macros**
           It is possible to define display filter macros. Macro are names
           that are replaced with the associated expression, possibly
           performing argument substitution. Macro expansions are purely
           textual replacements and performed recursively before compilation.
           They allow replacing long and often used expressions with easy to
           use names.
    
           Macros are defined using the GUI or directly in the "dmacros"
           configuration file. For example the definition
    
               "addplusone" {$1 + $2 + 1}
    
           creates a macro called addplusone that takes two arguments and
           expands to the given expression. Arguments in the replacement
           expression are given using the dollar sign.
    
           Macros are invoked like function but preceded with a dollar sign
           (sometimes also called a sigil):
    
               $addplusone(udp.src_port,udp.dst_port)
    
           results in the expression
    
               {udp.src_port + udp.dst_port + 1}
    
           after argument substitution. There is an older alternative
           notation to invoke macros:
    
               ${addplusone:udp.src_port;udp.dst_port}
    
           or
    
               ${addplusone;udp.src_port;udp.dst_port}
    
           Both forms are equivalent and can be used interchangibly as a
           matter of preference.
    
       **Protocol field types**
           Each protocol field is typed. The types are:
    
               ASN.1 object identifier, plain or relative
               AX.25 address
               Boolean
               Byte sequence
               Character string
               Character, 1 byte
               Date and time
               Ethernet or other MAC address
               EUI64 address
               Fibre Channel WWN
               Floating point, single or double precision
               Frame number
               Globally Unique Identifier
               IEEE-11073 floating point, 16 or 32 bits
               IPv4 address
               IPv6 address
               IPX network number
               Label
               OSI System-ID
               Protocol
               Signed integer, 1, 2, 3, 4, or 8 bytes
               Time offset
               Unsigned integer, 1, 2, 3, 4, or 8 bytes
               VINES address
    
           An integer may be expressed in decimal, octal, hexadecimal or
           binary notation, or as a C-style character constant. The following
           seven display filters are equivalent:
    
               frame.len > 10
               frame.len > 012
               frame.len > 0xa
               frame.len > 0b1010
               frame.len > '\n'
               frame.len > '\x0a'
               frame.len > '\012'
    
           Boolean values are either true or false. In a display filter
           expression testing the value of a Boolean field, true is expressed
           as the word true (case-insensitive) or any non-zero number. False
           is expressed as false (case-insensitive) or the number zero. For
           example, a token-ring packet’s source route field is Boolean. To
           find any source-routed packets, a display filter would be any of
           the following:
    
               tr.sr == 1
               tr.sr == true
               tr.sr == TRUE
    
           Non source-routed packets can be found with:
    
               tr.sr == 0
               tr.sr == false
               tr.sr == FALSE
    
           Ethernet addresses and byte arrays are represented by hex digits.
           The hex digits may be separated by colons, periods, or hyphens:
    
               eth.dst eq ff:ff:ff:ff:ff:ff
               aim.data == 0.1.0.d
               fddi.src == aa-aa-aa-aa-aa-aa
               echo.data == 7a
    
           IPv4 addresses can be represented in either dotted decimal
           notation or by using the hostname:
    
               ip.src == 192.168.1.1
               ip.dst eq www.mit.edu
    
           IPv4 addresses can be compared with the same logical relations as
           numbers: eq, ne, gt, ge, lt, and le. The IPv4 address is stored in
           host order, so you do not have to worry about the endianness of an
           IPv4 address when using it in a display filter.
    
           Classless Inter-Domain Routing (CIDR) notation can be used to test
           if an IPv4 address is in a certain subnet. For example, this
           display filter will find all packets in the 129.111 network:
    
               ip.addr == 129.111.0.0/16
    
           Remember, the number after the slash represents the number of bits
           used to represent the network. CIDR notation can also be used with
           hostnames, as in this example of finding IP addresses on the same
           network as 'sneezy' (requires that 'sneezy' resolve to an IP
           address for filter to be valid):
    
               ip.addr eq sneezy/24
    
           The CIDR notation can only be used on IP addresses or hostnames,
           not in variable names. So, a display filter like "ip.src/24 ==
           ip.dst/24" is not valid (yet).
    
           Transaction and other IDs are often represented by unsigned 16 or
           32 bit integers and formatted as a hexadecimal string with "0x"
           prefix:
    
               (dhcp.id == 0xfe089c15) || (ip.id == 0x0373)
    
           Strings are enclosed in double quotes:
    
               http.request.method == "POST"
    
           Inside double quotes, you may use a backslash to embed a double
           quote or an arbitrary byte represented in either octal or
           hexadecimal.
    
               browser.comment == "An embedded \" double-quote"
    
           Use of hexadecimal to look for "HEAD":
    
               http.request.method == "\x48EAD"
    
           Use of octal to look for "HEAD":
    
               http.request.method == "\110EAD"
    
           This means that you must escape backslashes with backslashes
           inside double quotes.
    
               smb.path contains "\\\\SERVER\\SHARE"
    
           looks for \\SERVER\SHARE in "smb.path". This may be more
           conveniently written as
    
               smb.path contains r"\\SERVER\SHARE"
    
           String literals prefixed with 'r' are called "raw strings". Such
           strings treat backslash as a literal character. Double quotes may
           still be escaped with backslash but note that backslashes are
           always preserved in the result.
    
           The following table lists all escape sequences supported with
           strings and character constants:
    
               \'          single quote
               \"          double quote
               \\          backslash
               \a          audible bell
               \b          backspace
               \f          form feed
               \n          line feed
               \r          carriage return
               \t          horizontal tab
               \v          vertical tab
               \NNN        arbitrary octal value
               \xNN        arbitrary hexadecimal value
               \uNNNN      Unicode codepoint U+NNNN
               \UNNNNNNNN  Unicode codepoint U+NNNNNNNN
    
           Date and time values can be given in ISO 8601 format or using a
           legacy month-year-time format:
    
               "2020-07-04T12:34:56"
               "Sep 26, 2004 23:18:04.954975"
    
           The 'T' separator in ISO 8601 can be omitted. The timezone can be
           given as "Z" or an offset from UTC.
    
           When not using ISO 8601 the timezone can be given as the strings
           "UTC", "GMT" or "UT" for UTC or also given as an offset from UTC,
           plus some North American and Nautical/Military designations (see
           the specification for %z in strptime(3)
           <https://man.netbsd.org/strptime.3>). Note that arbitrary timezone
           names are not supported however.
    
           If the timezone is omitted then date and time values are
           interpreted as local time.
    
       **The slice operator**
           You can take a slice of a field if the field base type is a text
           string or a byte array (the base type of most network address
           fields is bytes). For example, you can filter on the vendor
           portion of an ethernet address (the first three bytes) like this:
    
               eth.src[0:3] == 00:00:83
    
           Another example is:
    
               http.content_type[0:4] == "text"
    
           You can use the slice operator on a protocol name, too. The
           "frame" protocol can be useful, encompassing all the data captured
           by **Wireshark** or **TShark**.
    
               token[0:5] ne 0.0.0.1.1
               llc[0] eq aa
               frame[100-199] contains "wireshark"
    
           The following syntax governs slices:
    
               [i:j]    i = start_offset, j = length
               [i-j]    i = start_offset, j = end_offset, inclusive.
               [i]      i = start_offset, length = 1
               [:j]     start_offset = 0, length = j
               [i:]     start_offset = i, end_offset = end_of_field
    
           Slice indexes are zero-based. Offsets can be negative, in which
           case they indicate the offset from the **end** of the field. The last
           byte of the field is at offset -1, the last but one byte is at
           offset -2, and so on. Here’s how to check the last four bytes of a
           frame:
    
               frame[-4:4] == 0.1.2.3
    
           or
    
               frame[-4:] == 0.1.2.3
    
           As mentioned above the slice operator can be used on string and
           byte fields and will respectively produce string or byte slices.
           String slices are indexed on UTF-8 codepoint boundaries (i.e:
           internationalized characters), so the following comparison is
           true:
    
               "touché"[5] == "é"
    
           The example above generates an error because the compiler rejects
           constant expressions but is otherwise syntactically correct and
           exemplifies the behaviour of string slices.
    
           To obtain a byte slice of the same string the raw (@) operator can
           be used:
    
               @"touché"[5-6] == c3:a9
    
           A slice can always be compared against either a string or a byte
           sequence.
    
           Slices can be combined. You can concatenate them using the comma
           operator:
    
               ftp[1,3-5,9:] == 01:03:04:05:09:0a:0b
    
           This concatenates offset 1, offsets 3-5, and offset 9 to the end
           of the ftp data.
    
       **The layer operator**
           A field can be restricted to a certain layer in the protocol stack
           using the layer operator (#), followed by a decimal number:
    
               ip.addr#2 == 192.168.30.40
    
           matches only the inner (second) layer in the packet. Layers use
           simple stacking semantics and protocol layers are counted
           sequentially starting from 1. For example, in a packet that
           contains two IPv4 headers, the outer (first) source address can be
           matched with "ip.src#1" and the inner (second) source address can
           be matched with "ip.src#2".
    
           For more complicated ranges the same syntax used with slices is
           valid:
    
               tcp.port#[2-4]
    
           means layers number 2, 3 or 4 inclusive. The hash symbol is
           required to distinguish a layer range from a slice.
    
       **The at operator**
           By prefixing the field name with an at sign (@) the comparison is
           done against the raw packet data for the field.
    
           A character string must be decoded from a source encoding during
           dissection. If there are decoding errors the resulting string will
           usually contain replacement characters:
    
               browser.comment == "string is &#xFFFD;&#xFFFD;&#xFFFD;&#xFFFD;"
    
           The at operator allows testing the raw undecoded data:
    
               @browser.comment == 73:74:72:69:6e:67:20:69:73:20:aa:aa:aa:aa
    
           The syntactical rules for a bytes field type apply to the second
           example.
    
       **The membership operator**
           A field may be checked for matches against a set of values simply
           with the membership operator. For instance, you may find traffic
           on common HTTP/HTTPS ports with the following filter:
    
               tcp.port in {80,443,8080}
    
           as opposed to the more verbose:
    
               tcp.port == 80 or tcp.port == 443 or tcp.port == 8080
    
           To find HTTP requests using the HEAD or GET methods:
    
               http.request.method in {"HEAD", "GET"}
    
           The set of values can also contain ranges:
    
               tcp.port in {443, 4430..4434}
               ip.addr in {10.0.0.5 .. 10.0.0.9, 192.168.1.1..192.168.1.9}
               frame.time_delta in {10 .. 10.5}
    
       **Implicit type conversions**
           When fields which are sequences of bytes, including protocols, are
           compared with (double quoted) literal strings and raw strings, the
           literals are converted to their byte representation using the
           UTF-8 encoding. (To be precise, the original byte sequence is
           used, not the canonical normalized forms, so the precomposed é
           (U+00E9) and decomposed é (U+0065 U+0301) can match differently.)
    
           So, for instance, the following filters are equivalent:
    
               tcp.payload contains "GET"
               tcp.payload contains 47.45.54
    
           As noted above, a slice can also be compared in either way:
    
               frame[60:2] gt 50.51
               frame[60:2] gt "PQ"
    
           The inverse does not occur; stringlike fields are not implicitly
           converted to byte arrays. (Some operators allow stringlike fields
           to be compared with unquoted literals, which are then treated as
           strings; this is deprecated in general and specifically disallowed
           by the "matches" operator. Literal strings should be double quoted
           for clarity.)
    
           A hex integer that is 0xff or less (which means it fits inside one
           byte) can be implicitly converted to a byte string. This is not
           allowed for hex integers greater than one byte, because then one
           would need to specify the endianness of the multi-byte integer.
           Also, this is not allowed for decimal or octal numbers, since they
           would be confused with the hex numbers that make up byte string
           literals. Nevertheless, single-byte hex integers can be
           convenient:
    
               frame[4] == 0xff
               frame[1:4] contains 0x02
    
           An integer or boolean field that has a value string can be
           compared to to one of the strings that corresponds with a value.
           As with stringlike fields and comparisons, it is possible to
           perform the comparison with an unquoted literal, though this is
           deprecated and will not work if the literal contains a space (as
           with "Modify Bearer Response" above). Double quotes are
           recommended.
    
           If there is a unique reverse mapping from the string literal into
           a numeric value, the string is converted into that number and the
           comparison function is applied using arithmetic rules. If the
           mapping is not unique, then equality and inequality can be tested,
           but not the ordered comparisons.
    
           This is in contrast with the string() and vals() functions, which
           convert the field value to a string and applies string
           (lexicographic) comparisons, as well as work with all operators
           that take strings. Therefore the following two filters give the
           same result:
    
               gtpv2.message_type <= 35
               gtpv2.message_type <= "Modify Bearer Response"
    
           whereas
    
               vals(gtpv2.message_type) <= "Modify Bearer Response"
    
           matches all messages whose value string precedes "Modify Bearer
           Response" in lexicographical order, and
    
               string(gtpv2.message_type) <= "35"
    
           matches all messages such that the message type comes before "35"
           in lexicographical order, i.e. would also match "170" (the message
           type for "Release Access Bearers Request.")
    
           For the "contains" and "matches" operators, which operate on
           strings (or byte arrays in the case of "contains"), fields on the
           left hand side are implicitly converted to their value strings for
           comparison. (To compare a field with a byte array, use the raw/at
           (@) operator.)
    
       **Bitwise operators**
           It is also possible to define tests with bitwise operations.
           Currently the following bitwise operator is supported:
    
               bitand, bitwise_and, &        Bitwise AND
    
           The bitwise AND operation allows masking bits and testing to see
           if one or more bits are set. Bitwise AND operates on integer
           protocol fields and slices.
    
           When testing for TCP SYN packets, you can write:
    
               tcp.flags & 0x02
    
           That expression will match all packets that contain a "tcp.flags"
           field with the 0x02 bit, i.e. the SYN bit, set.
    
           To match locally administered unicast ethernet addresses you can
           use:
    
               eth.addr[0] & 0x0f == 2
    
           When using slices, the bit mask must be specified as a byte
           string, and it must have the same number of bytes as the slice
           itself, as in:
    
               ip[42:2] & 40:ff
    
       **Arithmetic operators**
           Arithmetic expressions are supported with the usual operators:
    
               +   Addition
               -   Subtraction
               *   Multiplication
               /   Division
               %   Modulo (integer remainder)
    
           Arithmetic operations can be performed on numeric types. Numeric
           types are integers, floating point numbers and date and time
           values.
    
           Date and time values can only be multiplied by integers or
           floating point numbers (i.e: scalars) and furthermore the scalar
           multiplier must appear on the right-hand side of the arithmetic
           operation.
    
           For example it is possible to filter for UDP destination ports
           greater or equal by one to the source port with the expression:
    
               udp.dstport >= udp.srcport + 1
    
           It is possible to group arithmetic expressions using curly
           brackets (parenthesis will not work for this):
    
               tcp.dstport >= 4 * {tcp.srcport + 3}
    
           Do not confuse this usage of curly brackets with set membership.
    
           An unfortunate quirk in the filter syntax is that the subtraction
           operator must be preceded by a space character, so "A-B" must be
           written as "A -B" or "A - B".
    
       **Protocol field references**
           A variable using a sigil with the form $some.proto.field or
           ${some.proto.field} is called a field reference. A field reference
           is a field value read from the currently selected frame in the
           GUI. This is useful to build dynamic filters such as, frames since
           the last five minutes to the selected frame:
    
               frame.time_relative >= ${frame.time_relative} - 300
    
           or more simply
    
               frame.time_relative >= $frame.time_relative - 300
    
           Field references share a similar notation to macros but are
           distinct syntactical elements in the filter language.
    
       **Logical expressions**
           Tests can be combined using logical expressions. These too are
           expressible in C-like syntax or with English-like abbreviations.
           The following table lists the logical operators from highest to
           lowest precedence:
    
               not, ! Logical NOT   (right-associative)
               and, &&   Logical AND   (left-associative)
               xor, ^^   Logical XOR   (left-associative)
               or,  ||   Logical OR    (left-associative)
    
           The evaluation is always performed left to right. Expressions can
           be grouped by parentheses as well. The expression "A and B or not
           C or D and not E or F" is read:
    
               (A and B) or (not C) or (D and (not E)) or F
    
           It’s usually better to be explicit about grouping using
           parenthesis. The following are all valid display filter
           expressions:
    
               tcp.port == 80 and ip.src == 192.168.2.1
               not llc
               http and frame[100-199] contains "wireshark"
               (ipx.src.net == 0xbad && ipx.src.node == 0.0.0.0.0.1) || ip
    
           Remember that whenever a protocol or field name occurs in an
           expression, the "exists" operator is implicitly called. The
           "exists" operator has the highest priority. This means that the
           first filter expression must be read as "show me the packets for
           which tcp.port exists and equals 80, and ip.src exists and equals
           192.168.2.1". The second filter expression means "show me the
           packets where not exists llc", or in other words "where llc does
           not exist" and hence will match all packets that do not contain
           the llc protocol. The third filter expression includes the
           constraint that offset 199 in the frame exists, in other words the
           length of the frame is at least 200.
    
           Because each comparison has an implicit exists test for field
           values care must be taken when using the display filter to remove
           noise from the packet trace. If, for example, you want to filter
           out all IP multicast packets to address 224.1.2.3, then using:
    
               ip.dst ne 224.1.2.3
    
           may be too restrictive. This is the same as writing:
    
               ip.dst and ip.dst ne 224.1.2.3
    
           The filter selects only frames that have the "ip.dst" field. Any
           other frames, including all non-IP packets, will not be displayed.
           To display the non-IP packets as well, you can use one of the
           following two expressions:
    
               not ip.dst or ip.dst ne 224.1.2.3
               not ip.dst eq 224.1.2.3
    
           The first filter uses "not ip.dst" to include all non-IP packets
           and then lets "ip.dst ne 224.1.2.3" filter out the unwanted IP
           packets. The second filter also negates the implicit existence
           test and so is a shorter way to write the first.
    


## FILTER FIELD REFERENCE



           The entire list of display filters is too large to list here. You
           can can find references and examples at the following locations:
    
           •   The online Display Filter Reference:
               https://www.wireshark.org/docs/dfref/
    
           •   _View:Internals:Supported Protocols_ in Wireshark
    
           •   tshark -G fields on the command line
    
           •   The Wireshark wiki: https://wiki.wireshark.org/DisplayFilters
    


## NOTES



           The wireshark-filter(4) manpage is part of the **Wireshark**
           distribution. The latest version of **Wireshark** can be found at
           https://www.wireshark.org.
    
           Regular expressions in the "matches" operator are provided by the
           PCRE2 library. See https://www.pcre.org/ for more information.
    
           This manpage does not describe the capture filter syntax, which is
           different. See the manual page of pcap-filter(7) or, if that
           doesn’t exist, tcpdump(8), or, if that doesn’t exist,
           https://wiki.wireshark.org/CaptureFilters for a description of
           capture filters.
    
           Display Filters are also described in the Wireshark User’s Guide
           <https://www.wireshark.org/docs/wsug_html_chunked/ChWorkBuildDisplayFilterSection.html>.
    


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