Network Working Group                                    Brooks Hickman
Internet-Draft                                   Spirent Communications
Expiration Date: December 2001                             David Newman
                                                           Network Test
                                                           Terry Martin
                                                          M2networx INC
                                                              June 2001

          Benchmarking Methodology for Firewall Performance
              <draft-ietf-bmwg-firewall-02.txt>

Status of this Memo

   This document is an Internet-Draft and is in full conformance with
   all provisions of Section 10 of RFC2026.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF), its areas, and its working groups.  Note that
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   Drafts.

   Internet-Drafts are draft documents valid for a maximum of six
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   at any time.  It is inappropriate to use Internet-Drafts as
   reference material or to cite them other than as "work in progress."

   The list of current Internet-Drafts can be accessed at
   http://www.ietf.org/ietf/1id-abstracts.txt

   The list of Internet-Draft Shadow Directories can be accessed at
   http://www.ietf.org/shadow.html.

Table of Contents

   1. Introduction . . . . . . . . . . . . . . . . . . . . . . . .  2
   2. Requirements . . . . . . . . . . . . . . . . . . . . . . . .  2
   3. Scope  . . . . . . . . . . . . . . . . . . . . . . . . . . .  2
   4. Test setup . . . . . . . . . . . . . . . . . . . . . . . . .  2
     4.1 Test Considerations   . . . . . . . . . . . . . . . . . .  3
     4.2 Virtual Client/Servers  . . . . . . . . . . . . . . . . .  3
     4.3 Test Traffic Requirements . . . . . . . . . . . . . . . .  4
     4.4 DUT/SUT Traffic Flows . . . . . . . . . . . . . . . . . .  4
     4.5 Multiple Client/Server Testing  . . . . . . . . . . . . .  5
     4.6 NAT(Network Address Translation)  . . . . . . . . . . . .  5
     4.7 Rule Sets . . . . . . . . . . . . . . . . . . . . . . . .  5
     4.8 Web Caching . . . . . . . . . . . . . . . . . . . . . . .  5
     4.9 Authentication  . . . . . . . . . . . . . . . . . . . . .  6
   5. Benchmarking Tests . . . . . . . . . . . . . . . . . . . . .  6
     5.1 Concurrent Connection Capacity  . . . . . . . . . . . . .  6
     5.2 Maximum Connection Setup Rate . . . . . . . . . . . . . .  7
     5.3 Connection Establishment Time . . . . . . . . . . . . . .  9
     5.4 Connection Teardown Time  . . . . . . . . . . . . . . . . 11
     5.5 Denial Of Service Handling  . . . . . . . . . . . . . . . 13

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     5.6 HTTP  . . . . . . . . . . . . . . . . . . . . . . . . . . 14
     5.7 IP Fragmentation Handling . . . . . . . . . . . . . . . . 16
     5.8 Illegal Traffic Handling  . . . . . . . . . . . . . . . . 18
     5.9 Latency . . . . . . . . . . . . . . . . . . . . . . . . . 19
   Appendices  . . . . . . . . . . . . . . . . . . . . . . . . . . 22
     A. HyperText Transfer Protocol(HTTP)  . . . . . . . . . . . . 22
     B. References . . . . . . . . . . . . . . . . . . . . . . . . 23

1. Introduction

   This document provides methodologies for the performance
   benchmarking of firewalls. It provides methodologies in four areas:
   forwarding, connection, latency and filtering. In addition to
   defining the tests, this document also describes specific formats
   for reporting the results of the tests.

   A previous document, "Benchmarking Terminology for Firewall
   Performance" [1], defines many of the terms that are used in this
   document. The terminology document SHOULD be consulted before
   attempting to make use of this document.

2. Requirements

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED",  "MAY", and "OPTIONAL" in
   this document are to be interpreted as described in RFC 2119.

3. Scope

   Firewalls can provide a single point of defense between networks.
   Usually, a firewall protects private networks from the public or
   shared networks to which it is connected. A firewall can be as
   simple as a device that filters different packets or as complex
   as a group of devices that combine packet filtering and
   application-level proxy or network translation services. This RFC
   will focus on developing benchmark testing of DUT/SUTs, wherever
   possible, independent of their implementation.

4. Test Setup

   Test configurations defined in this document will be confined to
   dual-homed and tri-homed as shown in figure 1 and figure 2
   respectively.

   Firewalls employing dual-homed configurations connect two networks.
   One interface of the firewall is attached to the unprotected
   network, typically the public network(Internet). The other interface
   is connected to the protected network, typically the internal LAN.






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   In the case of dual-homed configurations, servers which are made
   accessible to the public(Unprotected) network are attached to the
   private(Protected) network.

      +----------+                                       +----------+
      |          |    |       +----------+        |      |          |
      | Servers/ |----|       |          |        |------| Servers/ |
      | Clients  |    |       |          |        |      | Clients  |
      |          |    |-------|  DUT/SUT |--------|      |          |
      +----------+    |       |          |        |      +----------+
                      |       +----------+        |
           Protected  |                           | Unprotected
            Network                                   Network
                           Figure 1(Dual-Homed)

   Tri-homed[1] configurations employ a third segment called a DMZ.
   With tri-homed configurations, servers accessible to the public
   network are attached to the DMZ. Tri-Homed configurations offer
   additional security by separating server accessible to the public
   network from internal hosts.


      +----------+                                       +----------+
      |          |    |       +----------+        |      |          |
      | Clients  |----|       |          |        |------| Servers/ |
      |          |    |       |          |        |      | Clients  |
      +----------+    |-------|  DUT/SUT |--------|      |          |
                      |       |          |        |      +----------+
                      |       +----------+        |
            Protected |            |              | Unprotected
             Network               |                   Network
                                   |
                                   |
                           -----------------
                                       |    DMZ
                                       |
                                       |
                                +-----------+
                                |           |
                                | Servers   |
                                |           |
                                +-----------+

                             Figure 2(Tri-Homed)

4.1 Test Considerations

4.2 Virtual Clients/Servers

   Since firewall testing may involve data sources which emulate
   multiple users or hosts, the methodology uses the terms virtual
   clients/servers. For these firewall tests, virtual clients/servers
   specify application layer entities which may not be associated with

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   a unique physical interface. For example, four virtual clients may
   originate from the same data source[1]. The test report SHOULD
   indicate the number of virtual clients and virtual servers
   participating in the test on a per interface(See 4.1.3) basis.

   Testers MUST synchronize all data sources participating in a test.

4.3 Test Traffic Requirements

   While the function of a firewall is to enforce access control
   policies, the criteria by which those policies are defined vary
   depending on the implementation. Firewalls may use network layer,
   transport layer or, in many cases, application-layer criteria to
   make access-control decisions. Therefore, the test equipment used to
   benchmark the DUT/SUT performance MUST consist of real clients and
   servers generating legitimate layer seven conversations.

   For the purposes of benchmarking firewall performance, HTTP 1.1
   will be referenced in this document, although the methodologies
   may be used as a template for benchmarking with other applications.
   Since testing may involve proxy based DUT/SUTs, HTTP version
   considerations are discussed in appendix A.

4.4 DUT/SUT Traffic Flows

   Since the number of interfaces are not fixed, the traffic flows will
   be dependent upon the configuration used in benchmarking the
   DUT/SUT. Note that the term "traffic flows" is associated with
   client-to- server requests.

   For Dual-Homed configurations, there are two unique traffic flows:

      Client           Server
      ------         ------
      Protected   -> Unprotected
      Unprotected -> Protected

   For Tri-Homed configurations, there are three unique traffic flows:

      Client          Server
      ------         ------
      Protected ->   Unprotected
      Protected ->   DMZ
      Unprotected -> DMZ










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4.5 Multiple Client/Server Testing

   One or more clients may target multiple servers for a given
   application. Each virtual client MUST initiate requests(Connection,
   object transfers, etc.) in a round-robin fashion. For example, if
   the test consisted of six virtual clients targeting three servers,
   the pattern would be as follows:


      Client          Target Server(In order of request)
      #1              1     2     3     1...
        #2              2     3     1     2...
        #3              3     1     2     3...
        #4              1     2     3     1...
        #5              2     3     1     2...
        #6              3     1     2     3...

4.6 NAT(Network Address Translation)

   Many firewalls implement network address translation(NAT), a
   function which translates internal host IP addresses attached to
   the protected network to a virtual IP address for communicating
   across the unprotected network(Internet). This involves additional
   processing on the part of the DUT/SUT and may impact performance.
   Therefore, tests SHOULD be ran with NAT disabled and NAT enabled
   to determine the performance differentials. The test report SHOULD
   indicate whether NAT was enabled or disabled.

4.7 Rule Sets

   Rule sets[1] are a collection of access control policies that
   determines which packets the DUT/SUT will forward and which it will
   reject. The criteria by which these access control policies may be
   defined will vary depending on the capabilities of the DUT/SUT. The
   scope of this document is limited to how the rule sets should be
   applied when testing the DUT/SUT.

   The firewall monitors the incoming traffic and checks to make sure
   that the traffic meets one of the defined rules before allowing it
   to be forwarded. It is RECOMMENDED that a rule be entered for each
   host(Virtual client). Although many firewalls permit groups of IP
   addresses to be defined for a given rule, tests SHOULD be performed
   with large rule sets, which are more stressful to the DUT/SUT.

   The DUT/SUT SHOULD be configured to denies access to all traffic
   which was not previously defined in the rule set.

4.7 Web Caching

   Some firewalls include caching agents in order to reduce network
   load. When making a request through a caching agent, the caching
   agent attempts to service the response from its internal memory.


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   The cache itself saves responses it receives, such as responses
   for HTTP GET requests. The report SHOULD indicate whether caching
   was enabled or disabled on the DUT/SUT.

4.8 Authentication

   Access control may involve authentication processes such as user,
   client or session authentication. Authentication is usually
   performed by devices external to the firewall itself, such as an
   authentication servers and may add to the latency of the system.
   Any authentication processes MUST be included as part of connection
   setup process.

5. Benchmarking Tests

5.1 Concurrent Connection Capacity

5.1.1 Objective

   To determine the maximum number of concurrent connections through
   or with the DUT/SUT, as defined in RFC2647[1]. This test will employ
   a step algorithm to obtain the maximum number of concurrent TCP
   connections that the DUT/SUT can maintain.

5.1.2 Setup Parameters

   The following parameters MUST be defined for all tests.

   Connection Attempt Rate - The rate, expressed in connections per
   second, at which new TCP connection requests are attempted. The
   rate SHOULD be set lower than maximum rate at which the DUT/SUT can
   accept connection requests.

   Connection Step Count - Defines the number of additional TCP
   connections attempted for each iteration of the step search
   algorithm.

   Object Size - Defines the number of bytes to be transferred in
   response to a HTTP 1.1 GET request . It is RECOMMENDED to use the
   minimum object size supported by the media.

5.1.3 Procedure

   Each virtual client will attempt to establish TCP connections to its
   target server(s), using either the target server's IP address or NAT
   proxy address, at a fixed rate in a round robin fashion. Each
   iteration will involve the virtual clients attempting to establish a
   fixed number of additional TCP connections. This search algorithm
   will be repeated until either:

      - One or more of the additional connection attempts fail to
        complete.
      - One or more of the previously established connections fail.

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   The test MUST also include application layer data transfers in
   order to validate the TCP connections since, in the case of proxy
   based DUT/SUTs, the tester does not own both sides of the
   connection. For the purposes of validation, the virtual client(s)
   will request an object from its target server(s) using an HTTP 1.1
   GET request, with both the client request and server response
   excluding the connection-token close in the connection header. In
   addition, periodic HTTP GET requests MAY be required to keep the
   underlying TCP connection open(See Appendix A).

5.1.4 Measurements

   Maximum concurrent connections - Total number of TCP connections
   open for the last successful iteration performed in the search
   algorithm.

5.1.5 Reporting Format

   5.1.5.1 Transport-Layer Reporting:

   The test report MUST note the connection attempt rate, connection
   step count and maximum concurrent connections measured.

   5.1.5.2 Application-Layer Reporting:

   The test report MUST note the object size(s) and the use of
   HTTP 1.1 client and server.

   5.1.5.3 Log Files

   A log file MAY be generated which includes the TCP connection
   attempt rate, HTTP object size and for each iteration:

      - Step Iteration
        - Pass/Fail Status.
      - Total TCP connections established.
      - Number of previously established TCP connections dropped.
      - Number of the additional TCP connections that failed to
        complete.

5.2 Maximum Connection Setup Rate

5.2.1 Objective

   To determine the maximum TCP connection setup rate through or with
   the DUT/SUT, as defined by RFC2647[1]. This test will employ a
   search algorithm to obtain the maximum rate at which TCP connections
   can be established through or with the DUT/SUT.






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5.2.2 Setup Parameters

   The following parameters MUST be defined.

   Initial Attempt Rate - The rate, expressed in connections per
   second, at which the initial TCP connection requests are attempted.

   Number of Connections - Defines the number of TCP connections that
   must be established. The number MUST be between the number of
   participating virtual clients and the maximum number supported by
   the DUT/SUT. It is RECOMMENDED not to exceed the concurrent
   connection capacity found in section 5.1.

   Connection Teardown Rate - The rate, expressed in connections per
   second, at which the tester will attempt to teardown TCP connections
   between each iteration. The connection teardown rate SHOULD be set
   lower than rate at which the DUT/SUT can teardown TCP connections.

   Age Time - The time, expressed in seconds, the DUT/SUT will keep a
   connection in it's state table after receiving a TCP FIN or RST
   packet.

   Object Size - Defines the number of bytes to be transferred in
   response to a HTTP 1.1 GET request . It is RECOMMENDED to use the
   minimum object size supported by the media.

5.2.3 Procedure

   An iterative search algorithm will be used to determine the maximum
   connection rate. This test iterates through different connection rates
   with a fixed number of connections attempted by the virtual clients to
   their associated server(s).

   Each iteration will use the same connection establishment and
   connection validation algorithms defined in the concurrent capacity
   test(See section 5.1).

   Between each iteration of the test, the tester must close all
   connections completed for the previous iteration. In addition,
   it is RECOMMENDED to abort all unsuccessful connections attempted.
   The tester will wait for the period of time, specified by age time,
   before continuing to the next iteration.

5.2.4 Measurements

   Highest connection rate - Highest rate, in connections per second,
   for which all TCP connections completed successfully.







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5.2.5 Reporting Format

   5.2.5.1 Transport-Layer Reporting:

   The test report MUST note the number of connections attempted,
   connection teardown rate, age time,  and highest connection rate
   measured.

   5.1.5.2 Application-Layer Reporting:

   The test report MUST note the object size(s) and the use of
   HTTP 1.1 client and server.
   5.1.5.3 Log Files

   A log file MAY be generated which includes the total TCP connections
   attempt, TCP connection teardown rate, age time, HTTP object size and
   for each iteration:

      - Step Iteration
        - Pass/Fail Status.
      - Total TCP connections established.
      - Number of TCP connections that failed to complete.

5.3 Connection Establishment Time

5.3.1 Objective

  To determine the connection establishment times[1] through or with
  the DUT/SUT as a function of the number of open connections.

  A connection for a client/server application is not atomic, in that
  it not only involves transactions at the application layer, but
  involves first establishing a connection using one or more underlying
  connection oriented protocols(TCP, ATM, etc). Therefore, it is
  encouraged to make separate measurements for each connection oriented
  protocol required in order to perform the application layer
  transaction.

5.3.2 Setup Parameters

   The following parameters MUST be defined.

   Connection Attempt Rate - The rate, expressed in connections per
   second, at which new TCP connection requests are attempted. It is
   RECOMMENDED not to exceed the maximum connection rate found in
   section 5.2.

   Connection Attempt Step count - Defines the number of additional
   TCP connections attempted for each iteration of the step algorithm.

   Maximum Attempt Connection Count - Defines the maximum number of
   TCP connections attempted in the test. It is RECOMMENDED not to
   exceed the concurrent connection capacity found in section 5.1.

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   Object Size - Defines the number of bytes to be transferred in
   response to a HTTP 1.1 GET request.

   Number of requests - Defines the number of HTTP 1.1 GET requests
   per connection. Note that connection, in this case, refers to the
   underlying transport protocol.

5.3.3 Procedure

   Each virtual client will attempt to establish TCP connections to its
   target server(s) at a fixed rate in a round robin fashion. Each
   iteration will involve the virtual clients attempting to establish
   a fixed number of additional connections until the maximum attempt
   connection count is reached.

   As with the concurrent capacity tests, application layer data
   transfers will be performed. Each virtual client(s) will request
   one or more objects from its target server(s) using one or more
   HTTP 1.1 GET request, with both the client request and server
   response excluding the connection-token close in the connection
   header. In addition, periodic HTTP GET requests MAY be required to
   keep the underlying TCP connection open(See appendix A).

   Since testing may involve proxy based DUT/SUTs, which terminates the
   TCP connection, making a direct measurement of the TCP connection
   establishment time is not possible since the protocol involves an
   odd number of messages in establishing a connection. Therefore, when
   testing with proxy based firewalls, the datagram following the final
   ACK on the three-way handshake will be used in determining the
   connection setup time.

   The following shows the timeline for the TCP connection setup
   involving a proxy DUT/SUT and is referenced in the measurement
   section. Note that this method may be applied when measuring other
   connection oriented protocols involving an odd number of messages
   in establishing a connection.

      t0: Client sends a SYN.
      t1: Proxy sends a SYN/ACK.
      t2: Client sends the final ACK.
      t3: Proxy establishes separate connection with server.
      t4: Client sends TCP datagram to server.
      *t5: Proxy sends ACK of the datagram to client.


   * While t5 is not considered part of the TCP connection establishment,
     acknowledgement of t4 must be received for the connection to be
     considered successful.






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5.3.4 Measurements
  For each iteration of the test, the tester MUST measure the minimum,
  maximum and average TCP connection establishment times. Measuring TCP
  connection establishment times will be made two different ways,
  depending on whether or not the DUT/SUT is proxy based. If proxy
  based, the connection establishment time is considered to be from the
  time the first bit of the SYN packet is transmitted by the client to
  the time the client transmits the first bit of the TCP datagram,
  provided that the TCP datagram gets acknowledged(t4-t0 in the above
  timeline). For DUT/SUTs that are not proxy based, the establishment
  time shall be directly measured and is considered to be from the time
  the first bit of the SYN packet is transmitted by the client to the
  time the last bit of the final ACK in the three-way handshake is
  received by the target server.

  In addition, the tester SHOULD measure the minimum, maximum and
  average connection establishment times for all other underlying
  connection oriented protocols which are required to be established
  for the client/server application to transfer an object. Each
  connection oriented protocol has its own set of transactions
  required for establishing a connection between two hosts or a host
  and DUT/SUT. For purposes of benchmarking firewall performance, the
  connection establishment time will be considered the interval
  between the transmission of the first bit of the first octet of the
  packet carrying the connection request to receipt of the last bit of
  the last octet of the last packet of the connection setup traffic
  received on the client or server, depending on whether a given
  connection requires an even or odd number of messages, respectfully.

5.3.5 Reporting Format

   The test report MUST note the TCP connection attempt rate, TCP
   connection attempt step count and maximum TCP connections attempted,
   HTTP object size and number of requests per connection.

   For each connection oriented protocol the tester measured, the
   connection establishment time results SHOULD be in tabular form
   with a row for each iteration of the test. There SHOULD be a column
   for the iteration count, minimum connection establishment time,
   average connection establishment time, maximum connection
   establishment time, attempted connections completed, attempted
   connections failed.

5.4 Connection Teardown Time

5.4.1 Objective

   To determine the connection teardown time[1] through or with the
   DUT/SUT as a function of the number of open connections. As with the
   connection establishment time, separate measurements will be taken
   for each connection oriented protocol involved in closing a
   connection.

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5.4.2 Setup Parameters

   The following parameters MUST be defined. Each parameters is
   configured with the following considerations.

   Initial connections - Defines the number of TCP connections to
   initialize the test with. It is RECOMMENDED not to exceed the
   concurrent connection capacity found in section 5.1.

   Initial connection rate - Defines the rate, in connections per
   second, at which the initial TCP connections are attempted. It is
   RECOMMENDED not to exceed the maximum Connection setup rate found
   in section 5.2.

   Teardown attempt rate - The rate at which the tester will attempt
   to teardown TCP connections.

   Teardown step count - Defines the number of TCP connections the
   tester will attempt to teardown for each iteration of the step
   algorithm.

   Object size - Defines the number of bytes to be transferred across
   each connection in response to an HTTP 1.1 GET request during the
   initialization phase of the test as well as periodic GET requests,
   if required.

5.4.3 Procedure

   Prior to beginning a step algorithm, the tester will initialize
   the test by establishing connections defined by initial connections.
   The test will use the same algorithm for establishing the connection
   as described in the connection capacity test(Section 5.1).

   For each iteration of the step algorithm, the tester will attempt
   teardown the number of connections defined by teardown step count
   at a rate defined by teardown attempt rate. This will be repeated
   until the tester has attempted to teardown all of the connections.

5.4.4 Measurements

   For each iteration of the test, the tester MUST measure the minimum,
   average and maximum connection teardown times. As with the
   connection establishment time test, the tester SHOULD measure all
   connection oriented protocols which are being torn down.

5.4.5 Reporting Format

   The test report MUST note the initial connections, initial
   connection rate, teardown attempt rate, teardown step count and
   object size.




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   For each connection oriented protocol the tester measured, the
   connection teardown time results SHOULD be in tabular form
   with a row for each iteration of the test. There SHOULD be a column
   for the iteration count, minimum connection teardown time,
   average connection teardown time, maximum connection teardown
   time, attempted teardowns completed, attempted teardown failed.

5.5 Denial Of Service Handling

5.5.1 Objective

   To determine the effect of a denial of service attack on a DUT/SUTs
   connection establishment rates and/or goodput. The Denial Of Service
   Handling test MUST be run after obtaining baseline measurements
   from sections 5.2 and/or 5.6.

   The TCP SYN flood attack exploits TCP's three-way handshake mechanism
   by having an attacking source host generate TCP SYN packets with
   random source addresses towards a victim host, thereby consuming that
   host's resources.

   Some firewalls employ mechanisms to guard against SYN attacks. If such
   mechanisms exist on the DUT/SUT, tests SHOULD be run with these
   mechanisms enabled to determine how well the DUT/SUT can maintain,
   under such attacks, the baseline connection rates and goodput determined
   in section 5.2 and section 5.6, respectively.

5.5.2 Setup Parameters

   Use the same setup parameters as defined in section 5.2.2 or 5.6.2,
   depending on whether testing against the baseline connection setup
   rate test or goodput test, respectfully.

   In addition, the following setup parameters MUST be defined.

   SYN Attack Rate - Defines the rate, in packets per second at which
   the server(s) are targeted with TCP SYN packets.

5.5.3 Procedure

   Use the same procedure as defined in section 5.2.3 or 5.6.3, depending
   on whether testing against the baseline connection setup rate test or
   goodput test, respectfully. In addition, the tester will generate TCP
   SYN packets targeting the server(s) IP address or NAT proxy address at
   a rate defined by SYN attack rate.

   The tester originating the TCP SYN attack MUST be attached to the
   unprotected network. In addition, the tester MUST not respond to the
   SYN/ACK packets sent by target server in response to the SYN packet.





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5.5.4 Measurements
   Perform the same measurements as defined in section 5.2.4 or 5.6.4,
   depending on whether testing against the baseline connection setup
   rate test or goodput test, respectfully.

   In addition, the tester SHOULD track SYN packets associated with the
   SYN attack which the DUT/SUT forwards on the protected or DMZ
   interface(s).

5.5.5 Reporting Format

   The test SHOULD use the same reporting format as described in
   section 5.2.5 or 5.6.5, depending on whether testing against
   baseline throughput rates or goodput, respectively.

   In addition, the report MUST indicate a denial of service handling
   test, SYN attack rate, number SYN attack packets transmitted and
   number of SYN attack packets received and whether or not the DUT
   has any SYN attack mechanisms enabled.

5.6 HTTP

5.6.1 Objective

   To determine the goodput, as defined by RFC2647, of the DUT/SUT
   when presented with HTTP traffic flows. The goodput measurement
   will be based on HTTP objects forwarded to the correct destination
   interface of the DUT/SUT.

5.6.2 Setup Parameters

   The following parameters MUST be defined.

   Number of sessions - Defines the number of HTTP 1.1 sessions to be
   attempted for transferring an HTTP object(s). Number MUST be equal
   or greater than the number of virtual clients participating in the
   test. The number SHOULD be a multiple of the virtual clients
   participating in the test. Note that each session will use one
   underlying transport layer connection.
   Session rate - Defines the rate, in sessions per second, that the
   HTTP sessions are attempted.

   Requests per session - Defines the number of HTTP GET requests per
   session.

   Object Size - Defines the number of bytes to be transferred in
   response to an HTTP GET request.







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5.6.3 HTTP Procedure

   Each HTTP 1.1 virtual client will attempt to establish sessions
   to its HTTP 1.1 target server(s), using either the target server's
   IP address or NAT proxy address, at a fixed rate in a round robin
   fashion.

   Baseline measurements SHOULD be performed using a single GET request
   per HTTP session with the minimal object size supported by the media.
   If the tester makes multiple HTTP GET requests per session, it MUST
   request the same-sized object each time. Testers may run multiple
   iterations of this test with objects of different sizes. See
   appendix A when testing proxy based DUT/SUT regarding HTTP version
   considerations. 5.6.4 Measurement

   Aggregate Goodput - The aggregate bit forwarding rate of the
   requested HTTP objects. The measurement will start on receipt of the
   first bit of the first packet containing a requested object which
   has been successfully transferred and end on receipt of the last
   packet containing the last requested object that has been
   successfully transferred. The goodput, in bits per second, can be
   calculated using the following formula:

                  OBJECTS * OBJECTSIZE * 8
      Goodput =  --------------------------
                       DURATION

   OBJECTS - Objects successfully transferred

   OBJECTSIZE - Object size in bytes

   DURATION - Aggregate transfer time based on aforementioned time
              references.

5.6.5 Reporting Format

   The test report MUST note the object size(s), number of sessions,
   session rate and requests per session.

   The goodput results SHOULD be reported in tabular form with a row
   for each of the object sizes. There SHOULD be columns for the object
   size, measured goodput and number of successfully transferred
   objects.

   Failure analysis:

   The test report SHOULD indicate the number and percentage of HTTP
   sessions that failed to complete the requested number of
   transactions, with a transaction being the GET request and
   successfully returned object.




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   Version information:

   The test report MUST note the use of an HTTP 1.1 client and server.

5.7 IP Fragmentation

5.7.1 Objective

   To determine the performance impact when the DUT/SUT is presented
   with IP fragmented[5] traffic. IP datagrams which have been
   fragmented, due to crossing a network that supports a smaller
   MTU(Maximum Transmission Unit) than the actual datagram, may
   require the firewall to perform re-assembly prior to the datagram
   being applied to the rule set.

   While IP fragmentation is a common form of attack, either on the
   firewall itself or on internal hosts, this test will focus on
   determining how the additional processing associated with the
   re-assembly of the datagrams has on the goodput of the DUT/SUT.

5.7.2 Setup Parameters

   The following parameters MUST be defined.

   Trial duration - Trial duration SHOULD be set for 30 seconds.

   5.7.2.1 Non-Fragmented Traffic Parameters

   Session rate - Defines the rate, in sessions per second, that the
   HTTP sessions are attempted.

   Requests per session - Defines the number of HTTP GET requests per
   session.

   Object Size - Defines the number of bytes to be transferred in
   response to an HTTP GET request.

   5.7.2.1 Fragmented Traffic Parameters

   Packet size, expressed as the number of bytes in the IP/UDP packet,
   exclusive of link-layer headers and checksums.

   Fragmentation Length - Defines the length of the data portion of the
   IP datagram and MUST be multiple of 8. Testers SHOULD use the minimum
   value, but MAY use other sizes as well.

   Intended Load -  Intended load, expressed as percentage of media
   utilization.






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5.7.3 Procedure

   Each HTTP 1.1 virtual client will attempt to establish sessions
   to its HTTP 1.1 target server(s), using either the target server's
   IP address or NAT proxy address, at a fixed rate in a round robin
   fashion. At the same time, a client attached to the unprotected side
   of the network will offer a unidirectional stream of unicast UDP/IP
   packets to a server connected to the protected side of the network.
   The tester MUST offer IP/UDP packets in a steady state.

   Baseline measurements SHOULD be performed with a deny rule(s) that
   filters the fragmented traffic. If the DUT/SUT has logging
   capability, the log SHOULD be checked to determine if it contains
   the correct information regarding the fragmented traffic.

   The test SHOULD be repeated with the DUT/SUT rule set changed to
   allow the fragmented traffic through. When running multiple
   iterations of the test, it is RECOMMENDED to vary the fragment
   length while keeping all other parameters constant.

5.7.4 Measurements

   Aggregate Goodput - The aggregate bit forwarding rate of the
   requested HTTP objects.(See section 5.6). Only objects which have
   successfully completed transferring within the trial duration are
   to be included in the goodput measurement.

   Transmitted UDP/IP Packets - Number of UDP packets transmitted by
   client.

   Received UDP/IP Packets - Number of UDP/IP Packets received by
   server.

5.7.5 Reporting Format

   The test report MUST note the test duration.

   The test report MUST note the packet size(s), offered load(s) and
   IP fragmentation length of the UDP/IP traffic. It SHOULD also note
   whether the DUT/SUT egresses the offered UDP/IP traffic fragmented
   or not.

   The test report MUST note the object size(s), session rate and
   requests per session.

   The results SHOULD be reported in the format of a table with a
   row for each of the fragmentation lengths.  There SHOULD be columns
   for the fragmentation length, IP/UDP packets transmitted by client,
   IP/UDP packets received by server, HTTP object size, and measured
   goodput.




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5.8 Illegal Traffic Handling

5.8.1 Objective

   To determine the behavior of the DUT/SUT when presented with a
   combination of both legal and Illegal traffic flows. Note that
   Illegal traffic does not refer to an attack, but to traffic which
   has been explicitly defined by a rule(s) to drop.

5.8.2 Setup Parameters

   The following parameters MUST be defined.

   Number of sessions - Defines the number of HTTP 1.1 sessions to be
   attempted for transferring an HTTP object(s). Number MUST be equal
   or greater than the number of virtual clients participating in the
   test. The number SHOULD be a multiple of the virtual clients
   participating in the test. Note that each session will use one
   underlying transport layer connection.
   Session rate - Defines the rate, in sessions per second, that the
   HTTP sessions are attempted.

   Requests per session - Defines the number of HTTP GET requests per
   session.

   Object size - Defines the number of bytes to be transferred in
   response to an HTTP GET request.

   Illegal traffic percentage - Percentage of HTTP 1.1 sessions which
   have been explicitly defined in a rule(s) to drop.

5.8.3 Procedure

   Each HTTP 1.1 virtual client will attempt to establish sessions
   to its HTTP 1.1 target server(s), using either the target server's
   IP address or NAT proxy address, at a fixed rate in a round robin
   fashion.

   The tester MUST present the connection requests, both legal and
   illegal, in an evenly distributed manner. Many firewalls have
   the capability to filter on different traffic criteria( IP
   addresses, Port numbers, etc). Testers may run multiple
   iterations of this test with the DUT/SUT configured to filter
   on different traffic criteria.

5.8.4 Measurements

   Legal sessions allowed - Number and percentage of legal HTTP
   sessions which completed.

   Illegal session allowed - Number and percentage of illegal HTTP
   session which completed.


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5.8.5 Reporting Format

   The test report MUST note the number of sessions, session rate,
   requests per session, percentage of illegal sessions and measurement
   results.   The results SHOULD be reported in the form of a table with a row
   for each of the object sizes.  There SHOULD be columns for the
   object size, number of legal sessions attempted, number of legal
   sessions successful, number of illegal sessions attempted and number
   of illegal sessions successful.

5.9 Latency

5.9.1 Objective

   To determine the latency of network-layer or application-layer data
   traversing the DUT/SUT. RFC 1242 [3] defines latency.

5.9.2 Setup Parameters

   The following parameters MUST be defined:

   5.9.2.1 Network-layer Measurements

      Packet size, expressed as the number of bytes in the IP packet,
      exclusive of link-layer headers and checksums.

      Intended load, expressed as percentage of media utilization.

      Offered load, expressed as percentage of media utilization.

      Test duration, expressed in seconds.

      Test instruments MUST generate packets with unique timestamp signatures.

   5.9.2.2 Application-layer Measurements

      Object size, expressed as the number of bytes to be transferred across a
      connection in response to an HTTP GET request. Testers SHOULD use the
      minimum object size supported by the media, but MAY use other object
      sizes as well.

      Connection type. The tester MUST use one HTTP 1.1 connection for latency
      measurements.

      Number of objects requested.

      Number of objects transferred.

      Test duration, expressed in seconds.

      Test instruments MUST generate packets with unique timestamp signatures.



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5.9.3 Network-layer procedure

   A client will offer a unidirectional stream of unicast packets to a server.
   The packets MUST use a connectionless protocol like IP or UDP/IP.

   The tester MUST offer packets in a steady state. As noted in the latency
   discussion in RFC 2544 [4], latency measurements MUST be taken at the
   throughput level -- that is, at the highest offered load with zero packet
   loss. Measurements taken at the throughput level are the only ones that can
   legitimately be termed latency.

   It is RECOMMENDED that implementers use offered loads not only at the
   throughput level, but also at load levels that are less than or greater
   than the throughput level. To avoid confusion with existing terminology,
   measurements from such tests MUST be labeled as delay rather than latency.
   If desired, the tester MAY use a step test in which offered loads increment
   or decrement through a range of load levels.

   The duration of the test portion of each trial MUST be at least 30 seconds.

5.9.4 Application layer procedure

   An HTTP 1.1 client will request one or more objects from an HTTP 1.1 server
   using one or more HTTP GET requests. If the tester makes multiple HTTP GET
   requests, it MUST request the same-sized object each time. Testers may run
   multiple iterations of this test with objects of different sizes.

   Implementers MAY configure the tester to run for a fixed duration. In this
   case, the tester MUST report the number of objects requested and returned
   for the duration of the test. For fixed-duration tests it is RECOMMENDED
   that the duration be at least 30 seconds.

5.9.5 Measurements

   Minimum delay - The smallest delay incurred by data traversing the DUT/SUT
   at the network layer or application layer, as appropriate.

   Maximum delay - The largest delay incurred by data traversing the DUT/SUT
   at the network layer or application layer, as appropriate.

   Average delay - The mean of all measurements of delay incurred by data
   traversing the DUT/SUT at the network layer or application layer, as
   appropriate.

   Delay distribution - A set of histograms of all delay measurements observed
   for data traversing the DUT/SUT at the network layer or application layer,
   as appropriate.

5.9.6 Network-layer reporting format

   The test report MUST note the packet size(s), offered load(s) and test
   duration used.


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   The latency results SHOULD be reported in the format of a table with a row
   for each of the tested packet sizes.  There SHOULD be columns for the
   packet size, the intended rate, the offered rate, and the resultant latency
   or delay values for each test.

5.9.7 Application-layer reporting format

   The test report MUST note the object size(s) and number of requests and
   responses completed. If applicable, the report MUST note the test duration
   if a fixed duration was used.

   The latency results SHOULD be reported in the format of a table with a row
   for each of the object sizes.  There SHOULD be columns for the object size,
   the number of completed requests, the number of completed responses, and the
   resultant latency or delay values for each test.

   Failure analysis:

   The test report SHOULD indicate the number and percentage of HTTP GET
   request or responses that failed to complete within the test duration.

   Version information:

   The test report MUST note the use of an HTTP 1.1 client and server.






























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APPENDICES

APPENDIX A: HTTP(HyperText Transfer Protocol)

   The most common versions of HTTP in use today are HTTP/1.0 and
   HTTP/1.1 with the main difference being in regard to persistent
   connections.  HTTP 1.0, by default, does not support persistent
   connections. A separate TCP connection is opened up for each
   GET request the client wants to initiate and closed after the
   requested object transfer is completed. Some implementations of
   HTTP/1.0 supports persistence by adding an additional header
   to the request/response:

      Connection: Keep-Alive

   However, under HTTP 1.0, there is no official specification for
   how the keep-alive operates. In addition, HTTP 1.0 proxies do
   support persistent connection as they do not recognize the
   connection header.

   HTTP/1.1, by default, does support persistent connection and
   is therefore the version that is referenced in this methodology.
   When HTTP/1.1 entities want the underlying transport layer
   connection closed after a transaction has completed, the
   request/response will include a connection-token close in the
   connection header:

      Connection: close

   If no such connection-token is present, the connection remains
   open after the transaction is completed. In addition, proxy
   based DUT/SUTs may monitor the TCP connection and after a
   timeout, close the connection if no activity is detected. The
   duration of this timeout is not defined in the HTTP/1.1
   specification and will vary between DUT/SUTs. When performing
   concurrent connection testing, GET requests MAY need to be
   issued at a periodic rate so that the proxy does not close the
   TCP connection.

   While this document cannot foresee future changes to HTTP
   and it's impact on the methodologies defined herein, such
   changes should be accommodated for so that newer versions of
   HTTP may be used in benchmarking firewall performance.











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Appendix B.  References

  [1] D. Newman, "Benchmarking Terminology for Firewall Devices", RFC 2647,
           August 1999.

  [2] R. Fielding, J. Gettys, J. Mogul, H Frystyk, L.Masinter, P. Leach,
      T. Berners-Lee , "Hypertext Transfer Protocol -- HTTP/1.1",
      RFC 2616 June 1999

  [3] S. Bradner, editor. "Benchmarking Terminology for Network
      Interconnection Devices," RFC 1242, July 1991.

  [4] S. Bradner, J. McQuaid, "Benchmarking Methodology for Network
      Interconnect Devices," RFC 2544, March 1999.


  [5] David C. Clark, "IP Datagram Reassembly Algorithm", RFC 815 ,
      July 1982.


































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