ranonymize.conf - ranonymize(1) configuration file.
Copyright (c) 2000-2002 QoSient. All rights reserved.
This configuration file provides the ability to specify options for
argus data anoymization.
The anonymization clients have a small number of options for
controlling specific aspects of the anonymization function and its
Timestamps, Reference and Sequence Numbers
Ranonymize anonymizes various fields in Argus records, such as the
network addresses, protocol specific port numbers, timestamps,
transaction reference numbers, and the sequence numbers.
For some fields, specifically the timestamps, transaction reference
numbers and the sequence numbers, which are generally monotonically
increasing counters, a good anonymization technique is to shift the
values by a constant, so that the sequential relationships between
values is preserved.
The configuration provides some flexibility here, so that the user can
control fixed offset shifting anonymization. The constant value can be
generated by the anonymization client at "random", which is the default
behavior, or the user can provide a "fixed:x", where x is the fixed
offset. Of course, the keyword "none" can be used to turn off the
default anonymization for these values.
Ethernet Address Vendor Codes
When anonymizing ethernet addresses, ranonymize has the option to
preserve the vendor portion, if desired. This allows analytical
programs to differentiate anonymized data by vendor type. This feature
is turned off by default.
Ranonymize has the option to preserve the semantic that an address is a
broadcast address. This is very important when doing flow analysis for
either operational or performance managment tasks, using anonymized
IPv4 Address Anonymization
IPv4 address are composed of two parts, a network part and a host part.
Because the addressing strategy of a site may have integrated semantics
that would want to be retained in the anonymized addresses, IPv4
address anonymization involves specifying a one-to-one translation
table for both the network and host address spaces in an IPv4 address.
Once a new network address has been allocated, every occurence of that
network address will be substituted in the anonymizers output stream.
The host address space is anonymized in an independent but similar
Ranonymize allows you to specify the type of anonymization method used
in a number of categories. For network and host address conversion,
ranonymize can support "sequential", "random" or "no" anonymization.
Sequential anonymization involves allocating new addresses in a
monotonically increasing fashion on a first come first serve basis.
Random anonymization allocates random addresses from the working pool
of addresses, and "no" anonymization preserves the address type,
whether its network, host or both.
The default working pool of network addresses contains only non-
routable addresses, and starts with 10.0.0.0. All anonymized addresses
are treated as Class C network addresses, in order to conserve the
anonymization allocation demands.
As an example, if the first Argus record contained the addresses
22.214.171.124 and 126.96.36.199 as the source and destination, sequential
anonymization would generate the addresses 10.0.0.1 and 10.0.1.1 as the
new source and destination addresses. This is because, the two
addresses have differing network parts, 128.64.2 and 132.243.2, these
would be allocated 10.0.0 and 10.0.1 respectively (sequential
allocation). Because these are the first hosts to be allocated, the
host parts are both 1.
Random anonymization could generate 10.24.31.203 and 10.1.34.18 as
possible addresses, as both the Class C network address would be
allocated randomly from the 10 network space, and the host address part
would be allocated randomly from the possible host addresses.
Sequential randomization uses the least amount of memory and minimizes
anonymization processing time, while random provides better address
Implemenation note: currently only supporting sequential
Ranonymize has the option to preserve the network address hierarchy at
various levels of granularity. This allows you to preserve the
addressing relationships between addresses. The options are "cidr",
"class", "subnet" and "no".
Class network adddress heirarchy preservation, causes ranonymize() to
allocate new network addresses base on the address class. All CLASSA
network addresses will be allocated new addresses from the Class A
network pool. Network addresses will be allocated as 24 bit CIDR
addresses, in that the first 24 bits will map to a unique 24 network
address, and host addresses will be allocated from the 254 address pool
(0 and 255 can be preserved, see below).
Specific Network Address Aliasing
Ranonymize can be configured to perform specific network address
translation. These must be specified as 24 bit CIDR addresses.
RANON_PRESERVE_NET_ADDRESS_HIERARCHY must be set to "cidr", for this
feature to work.
Examples would be:
Specific Host Address Aliasing
Ranonymize can be configured to perform specific host address
translation. These addresses are allocated prior to reading any data,
and are removed from the potential network address pool, regardless of
the anonymization strategy. Feel free to list as many addresses that
you would like.
Examples would be:
Transport SAP Aliasing
Ranonymize can be configured to preserve specific ranges of port
numbers. For convenience, ranonymize() can be configured to preserve
the IANA well known port allocation range (0-1023), the registered
ports (1024-49151) and/or the private port range (49152 - 65535).
Also, ranonymize() can be configured to preserve specific port numbers.
These numbers are independent of protocol type, so if port 23461 is to
be preserved, it will be preserved for both tcp and udp based flows.
14 November 2001 RANONYMIZE.CONF(5)