draft-ietf-bmwg-firewall-07.txt   draft-ietf-bmwg-firewall-08.txt 
Benchmarking Working Group Brooks Hickman A new Request for Comments is now available in online RFC libraries.
Internet-Draft Spirent Communications
Expiration Date: April 2003 David Newman
Network Test
Saldju Tadjudin
Spirent Communications
Terry Martin
GVNW Consulting Inc
October 2002
Benchmarking Methodology for Firewall Performance
<draft-ietf-bmwg-firewall-07.txt>
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Copyright Notice
Copyright (C) The Internet Society (2002). All Rights Reserved.
Abstract
This document discusses and defines a number of tests that may be
used to describe the performance characteristics of firewalls. In
addition to defining the tests, this document also describes
specific formats for reporting the results of the tests.
This document is a product of the Benchmarking Methodology Working RFC 3511
Group (BMWG) of the Internet Engineering Task Force (IETF).
Table of Contents Title: Benchmarking Methodology for Firewall Performance
Author(s): B. Hickman, D. Newman, S. Tadjudin, T. Martin
Status: Informational
Date: April 2003
Mailbox: brooks.hickman@spirentcom.com,
dnewman@networktest.com,
Saldju.Tadjudin@spirentcom.com, tmartin@gvnw.com
Pages: 34
Characters: 67916
Updates/Obsoletes/SeeAlso: None
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 I-D Tag: draft-ietf-bmwg-firewall-08.txt
2. Requirements . . . . . . . . . . . . . . . . . . . . . . . . 2
3. Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
4. Test setup . . . . . . . . . . . . . . . . . . . . . . . . . 3
4.1 Test Considerations . . . . . . . . . . . . . . . . . . . 4
4.2 Virtual Client/Servers . . . . . . . . . . . . . . . . . 4
4.3 Test Traffic Requirements . . . . . . . . . . . . . . . . 4
4.4 DUT/SUT Traffic Flows . . . . . . . . . . . . . . . . . . 5
4.5 Multiple Client/Server Testing . . . . . . . . . . . . . 5
4.6 NAT(Network Address Translation) . . . . . . . . . . . . 5
4.7 Rule Sets . . . . . . . . . . . . . . . . . . . . . . . . 5
4.8 Web Caching . . . . . . . . . . . . . . . . . . . . . . . 6
4.9 Authentication . . . . . . . . . . . . . . . . . . . . . 6
4.10 TCP Stack Considerations . . . . . . . . . . . . . . . . 6
5. Benchmarking Tests . . . . . . . . . . . . . . . . . . . . . 6
5.1 IP throughput . . . . . . . . . . . . . . . . . . . . . . 6
5.2 Concurrent TCP Connection Capacity . . . . . . . . . . . 8
5.3 Maximum TCP Connection Establishment Rate . . . . . . . . 10
5.4 Maximum TCP Connection Tear Down Rate . . . . . . . . . . 12
5.5 Denial Of Service Handling . . . . . . . . . . . . . . . 14
5.6 HTTP Transfer Rate . . . . . . . . . . . . . . . . . . . 15
5.7 Maximum HTTP Transaction Rate . . . . . . . . . . . . . . 18
5.8 Illegal Traffic Handling . . . . . . . . . . . . . . . . 20
5.9 IP Fragmentation Handling . . . . . . . . . . . . . . . . 21
5.10 Latency . . . . . . . . . . . . . . . . . . . . . . . . 23
6. References . . . . . . . . . . . . . . . . . . . . . . . . . 25
7. Security Consideration . . . . . . . . . . . . . . . . . . . 26
8. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . 26
9. Authors' Addresses . . . . . . . . . . . . . . . . . . . . . 27
Appendix A - HyperText Transfer Protocol(HTTP) . . . . . . . . 28
Appendix B - Connection Establishment Time Measurements . . . . 28
Appendix C - Connection Tear Down Time Measurements . . . . . . 29
Full Copy Statement . . . . . . . . . . . . . . . . . . . . . . 30
1. Introduction URL: ftp://ftp.rfc-editor.org/in-notes/rfc3511.txt
This document provides methodologies for the performance This document discusses and defines a number of tests that may be used
benchmarking of firewalls. It provides methodologies in four areas: to describe the performance characteristics of firewalls. In addition
forwarding, connection, latency and filtering. In addition to to defining the tests, this document also describes specific formats
defining the tests, this document also describes specific formats
for reporting the results of the tests. for reporting the results of the tests.
A previous document, "Benchmarking Terminology for Firewall This document is a product of the Benchmarking Methodology Working
Performance" [1], defines many of the terms that are used in this Group IETF.
document. The terminology document SHOULD be consulted before
attempting to make use of this document.
2. Requirements
In this document, the words that are used to define the significance
of each particular requirement are capitalized. These words are:
* "MUST" This word, or the words "REQUIRED" and "SHALL" mean that
the item is an absolute requirement of the specification.
* "SHOULD" This word or the adjective "RECOMMENDED" means that
there may exist valid reasons in particular circumstances to
ignore this item, but the full implications should be understood
and the case carefully weighed before choosing a different
course.
* "MAY" This word or the adjective "OPTIONAL" means that this item
is truly optional. One vendor may choose to include the item
because a particular marketplace requires it or because it
enhances the product, for example; another vendor may omit the
same item.
An implementation is not compliant if it fails to satisfy one or more
of the MUST requirements. An implementation that satisfies all the
MUST and all the SHOULD requirements is said to be "unconditionally
compliant"; one that satisfies all the MUST requirements but not all
the SHOULD requirements is said to be "conditionally compliant".
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[1], typically the public network(Internet). The other
interface is connected to the protected network[1], typically the
internal LAN.
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
Demilitarized Zone(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(s)
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
a unique physical interface. For example, four virtual clients may
originate from the same data source[1]. The test report MUST
indicate the number of virtual clients and virtual servers
participating in the 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.
For the purposes of benchmarking firewall performance, this document
references HTTP 1.1 or higher as the application layer entity. 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
4.5 Multiple Client/Server Testing
One or more clients may target multiple servers for a given
application. Each virtual client MUST initiate connections 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 Network Address Translation(NAT)
Many firewalls implement network address translation(NAT)[1], a
function which translates private internet addresses to public
internet addresses. 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 differential, if any. The test report MUST indicate
whether NAT was enabled or disabled.
4.7 Rule Sets
Rule sets[1] are a collection of access control policies that
determine which packets the DUT/SUT will forward and which it will
reject[1]. Since criteria by which these access control policies may
be defined will vary depending on the capabilities of the DUT/SUT,
the following is limited to providing guidelines for configuring
rule sets when benchmarking the performance of the DUT/SUT.
It is RECOMMENDED that a rule be entered for each host(Virtual
client). In addition, testing SHOULD be performed using different
size rule sets to determine its impact on the performance of the
DUT/SUT. Rule sets MUST be configured in a manner, such that, rules
associated with actual test traffic are configured at the end of the
rule set and not the beginning.
The DUT/SUT SHOULD be configured to deny access to all traffic which
was not previously defined in the rule set. The test report SHOULD
include the DUT/SUT configured rule set(s).
4.8 Web Caching
Some firewalls include caching agents to reduce network load. When
making a request through a caching agent, the caching agent attempts
to service the response from its internal memory. The cache itself
saves responses it receives, such as responses for HTTP GET
requests. Testing SHOULD be performed with any caching agents on the
DUT/SUT disabled.
4.9 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 server(s) and may add to the latency of the system.
Any authentication processes MUST be included as part of connection
setup process.
4.10 TCP Stack Considerations
Some test instruments allow configuration of one or more TCP stack
parameters, thereby influencing the traffic flows which will be
offered and impacting performance measurements. While this document
does not attempt to specify which TCP parameters should be
configurable, any such TCP parameter(s) MUST be noted in the test
report. In addition, when comparing multiple DUT/SUTs, the same TCP
parameters MUST be used.
5. Benchmarking Tests
5.1 IP Throughput
5.1.1 Objective
To determine the throughput of network-layer data transversing the
DUT/SUT, as defined in RFC1242[1]. Note that while RFC1242 uses the
term frames, which is associated with the link layer, the procedure
uses the term packets, since it is referencing the network layer.
5.1.2 Setup Parameters
The following parameters MUST be defined:
Packet size - Number of bytes in the IP packet, exclusive of any
link layer header or checksums.
Test Duration - Duration of the test, expressed in seconds.
5.1.3 Procedure
The tester MUST offer unicast IP packets traffic to the DUT/SUT at a
constant rate. The test MAY consist of either bi-directional or
unidirectional traffic; for example, an emulated client may offer a
unicast stream of packets to an emulated server, or the tester may
simulate a client/server exchange by offering bidirectional traffic.
The test MAY employ an iterative search algorithm. Each iteration
will involve the tester varying the intended load until the maximum
rate, at which no packet loss occurs, is found. Since backpressure
mechanisms may be employed, resulting in the intended load and
offered load being different, the test SHOULD be performed in either
a packet based or time based manner as described in RFC2889[7]. As
with RFC1242, the term packet is used in place of frame. The
duration of the test portion of each trial MUST be at least 30
seconds.
It is RECOMMENDED to perform the throughput measurements with
different packet sizes. When testing with different packet sizes the
DUT/SUT configuration MUST remain the same.
5.1.4 Measurement
5.1.4.1 Network Layer
Throughput - Maximum offered load, expressed in either bits per
second or packets per second, at which no packet loss is detected.
The bits to be counted are in the IP packet (header plus payload);
other fields, such as link-layer headers and trailers, MUST NOT be
included in the measurement.
Forwarding Rate - Forwarding rate, expressed in either bits per
second or packets per second, the device is observed to successfully
forward to the correct destination interface in response to a
specified offered load. The bits to be counted are in the IP packet
(header plus payload); other fields, such as link-layer headers and
trailers, MUST NOT be included in the measurement.
5.1.4 Reporting Format
The test report MUST note the packet size(s), test duration,
throughput and forwarding rate. If the test involved offering
packets which target more than one segment(Protected, Unprotected
or DMZ), the report MUST identify the results as an aggregate
throughput measurement.
The throughput 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 load, the offered load,
resultant throughput and forwarding rate for each test.
The intermediate results of the search algorithm MAY be saved in log
file which includes the packet size, test duration and for each
iteration:
- Step Iteration
- Pass/Fail Status
- Total packets offered
- Total packets forwarded
- Intended load
- Offered load(If applicable)
- Forwarding rate
5.2 Concurrent TCP Connection Capacity
5.2.1 Objective
To determine the maximum number of concurrent TCP connections
supported through or with the DUT/SUT, as defined in RFC2647[1].
This test is intended to find the maximum number of entries the
DUT/SUT can store in its connection table.
5.2.2 Setup Parameters
The following parameters MUST be defined for all tests:
5.2.2.1 Transport-Layer Setup Parameters
Connection Attempt Rate - The aggregate rate, expressed in
connections per second, at which TCP connection requests are
attempted. The rate SHOULD be set at or lower than the maximum
rate at which the DUT/SUT can accept connection requests.
Aging Time - The time, expressed in seconds, the DUT/SUT will
keep a connection in its connection table after receiving a TCP
FIN or RST packet.
5.2.2.2 Application-Layer Setup Parameters
Validation Method - HTTP 1.1 or higher MUST be used for this
test.
Object Size - Defines the number of bytes, excluding any bytes
associated with the HTTP header, to be transferred in response to
an HTTP 1.1 or higher GET request.
5.2.3 Procedure
An iterative search algorithm MAY be used to determine the maximum
number of concurrent TCP connections supported through or with the
DUT/SUT.
For each iteration, the aggregate number of concurrent TCP
connections attempted by the virtual client(s) will be varied. The
destination address will be that of the server or that of the NAT
proxy. The aggregate rate will be defined by connection attempt
rate, and will be attempted in a round-robin fashion(See 4.5).
To validate all connections, the virtual client(s) MUST request an
object using an HTTP 1.1 or higher GET request. The requests MUST be
initiated on each connection after all of the TCP connections have
been established.
When testing proxy-based DUT/SUTs, the virtual client(s) MUST
request two objects using HTTP 1.1 or higher GET requests. The first
GET request is required for connection time establishment[1]
measurements as specified in appendix B. The second request is used
for validation as previously mentioned. When comparing proxy and
non-proxy based DUT/SUTs, the test MUST be performed in the same
manner.
Between each iteration, it is RECOMMENDED that the tester issue a
TCP RST referencing each connection attempted for the previous
iteration, regardless of whether or not the connection attempt was
successful. The tester will wait for aging time before continuing to
the next iteration.
5.2.4 Measurements
5.2.4.1 Application-Layer measurements
Number of objects requested
Number of objects returned
5.2.4.2 Transport-Layer measurements
Maximum concurrent connections - Total number of TCP connections
open for the last successful iteration performed in the search
algorithm.
Minimum connection establishment time - Lowest TCP connection
establishment time measured as defined in appendix B.
Maximum connection establishment time - Highest TCP connection
establishment time measured as defined in appendix B.
Average connection establishment time - The mean of all
measurements of connection establishment times.
Aggregate connection establishment time - The total of all
measurements of connection establishment times.
5.2.5 Reporting Format
5.2.5.1 Application-Layer Reporting:
The test report MUST note the object size, number of completed
requests and number of completed responses.
The intermediate results of the search algorithm MAY be reported
in a tabular format with a column for each iteration. There
SHOULD be rows for the number of requests attempted, number and
percentage requests completed, number of responses attempted,
number and percentage of responses completed. The table MAY be
combined with the transport-layer reporting, provided that the
table identify this as an application layer measurement.
Version information:
The test report MUST note the version of HTTP client(s) and
server(s).
5.2.5.2 Transport-Layer Reporting:
The test report MUST note the connection attempt rate, aging time,
minimum TCP connection establishment time, maximum TCP connection
establishment time, average connection establishment time, aggregate
connection establishment time and maximum concurrent connections
measured.
The intermediate results of the search algorithm MAY be reported in
the format of a table with a column for each iteration. There SHOULD
be rows for the total number of TCP connections attempted, number
and percentage of TCP connections completed, minimum TCP connection
establishment time, maximum TCP connection establishment time,
average connection establishment time and the aggregate connection
establishment time.
5.3 Maximum TCP Connection Establishment Rate
5.3.1 Objective
To determine the maximum TCP connection establishment rate through
or with the DUT/SUT, as defined by RFC2647[1]. This test is intended
to find the maximum rate the DUT/SUT can update its connection
table.
5.3.2 Setup Parameters
The following parameters MUST be defined for all tests:
5.3.2.1 Transport-Layer Setup Parameters
Number of Connections - Defines the aggregate number of TCP
connections that must be established.
Aging 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.
5.3.2.2 Application-Layer Setup Parameters
Validation Method - HTTP 1.1 or higher MUST be used for this
test.
Object Size - Defines the number of bytes, excluding any bytes
associated with the HTTP header, to be transferred in response to
an HTTP 1.1 or higher GET request.
5.3.3 Procedure
An iterative search algorithm MAY be used to determine the maximum
rate at which the DUT/SUT can accept TCP connection requests.
For each iteration, the aggregate rate at which TCP connection
requests are attempted by the virtual client(s) will be varied. The
destination address will be that of the server or that of the NAT
proxy. The aggregate number of connections, defined by number of
connections, will be attempted in a round-robin fashion(See 4.5).
The same application-layer object transfers required for validation
and establishment time measurements as described in the concurrent
TCP connection capacity test MUST be performed.
Between each iteration, it is RECOMMENDED that the tester issue a
TCP RST referencing each connection attempted for the previous
iteration, regardless of whether or not the connection attempt was
successful. The tester will wait for aging time before continuing to
the next iteration.
5.3.4 Measurements
5.3.4.1 Application-Layer measurements
Number of objects requested
Number of objects returned
5.3.4.2 Transport-Layer measurements
Highest connection rate - Highest rate, in connections per
second, for which all connections successfully opened in the
search algorithm.
Minimum connection establishment time - Lowest TCP connection
establishment time measured as defined in appendix B.
Maximum connection establishment time - Highest TCP connection
establishment time measured as defined in appendix B.
Average connection establishment time - The mean of all
measurements of connection establishment times.
Aggregate connection establishment time - The total of all
measurements of connection establishment times.
5.3.5 Reporting Format
5.3.5.1 Application-Layer Reporting:
The test report MUST note object size(s), number of completed
requests and number of completed responses.
The intermediate results of the search algorithm MAY be reported
in a tabular format with a column for each iteration. There
SHOULD be rows for the number of requests attempted, number and
percentage requests completed, number of responses attempted,
number and percentage of responses completed. The table MAY be
combined with the transport-layer reporting, provided that the
table identify this as an application layer measurement.
Version information:
The test report MUST note the version of HTTP client(s) and
server(s).
5.3.5.2 Transport-Layer Reporting:
The test report MUST note the number of connections, aging time,
minimum TCP connection establishment time, maximum TCP connection
establishment time, average connection establishment time,
aggregate connection establishment time and highest connection
rate measured.
The intermediate results of the search algorithm MAY be reported
in the format of a table with a column for each iteration. There
SHOULD be rows for the connection attempt rate, total number of
TCP connections attempted, total number of TCP connections
completed, minimum TCP connection establishment time, maximum TCP
connection establishment time, average connection establishment
time and the aggregate connection establishment time.
5.4 Maximum TCP Connection Tear Down Rate
5.4.1 Objective
To determine the maximum TCP connection tear down rate through or
with the DUT/SUT, as defined by RFC2647[1].
5.4.2 Setup Parameters
Number of Connections - Defines the number of TCP connections that
will be attempted to be torn down.
Aging 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.
Close Method - Defines method for closing TCP connections. The test
MUST be performed with either a three-way or four-way handshake. In
a four-way handshake, each side sends separate FIN and ACK messages.
In a three-way handshake, one side sends a combined FIN/ACK message
upon receipt of a FIN.
Close Direction - Defines whether closing of connections are to be
initiated from the client or from the server.
5.4.3 Procedure
An iterative search algorithm MAY be used to determine the maximum
TCP connection tear down rate. The test iterates through different
TCP connection tear down rates with a fixed number of TCP
connections.
In the case of proxy based DUT/SUTs, the DUT/SUT will itself receive
the ACK in response to issuing a FIN packet to close its side of the
TCP connection. For validation purposes, the virtual client or
server, whichever is applicable, MAY verify that the DUT/SUT
received the final ACK by re-transmitting the final ACK. A TCP RST
should be received in response to the retransmitted ACK.
Between each iteration, it is RECOMMENDED that the virtual client(s)
or server(s), whichever is applicable, issue a TCP RST referencing
each connection which was attempted to be torn down, regardless of
whether or not the connection tear down attempt was successful. The
test will wait for aging time before continuing to the next
iteration.
5.4.4 Measurements
Highest connection tear down rate - Highest rate, in connections per
second, for which all TCP connections were successfully torn down in
the search algorithm.
The following tear down time[1] measurements MUST only include
connections for which both sides of the connection were successfully
torn down. For example, tear down times for connections which are
left in a FINWAIT-2[8] state should not be included:
Minimum connection tear down time - Lowest TCP connection tear down
time measured as defined in appendix C.
Maximum connection tear down time - Highest TCP connection tear down
time measured as defined in appendix C.
Average connection tear down time - The mean of all measurements of
connection tear down times.
Aggregate connection tear down time - The total of all measurements
of connection tear down times.
5.4.5 Reporting Format
The test report MUST note the number of connections, aging time,
close method, close direction, minimum TCP connection tear down
time, maximum TCP connection tear down time, average TCP connection
tear down time and the aggregate TCP connection tear down time and
highest connection tear down rate measured.
The intermediate results of the search algorithm MAY be reported in
the format of a table with a column for each iteration. There SHOULD
be rows for the number of TCP tear downs attempted, number and
percentage of TCP connection tear downs completed, minimum TCP
connection tear down time, maximum TCP connection tear down time,
average TCP connection tear down time, aggregate TCP connection tear
down time and validation failures, if required.
5.5 Denial Of Service Handling
5.5.1 Objective
To determine the effect of a denial of service attack on a DUT/SUT
TCP connection establishment and/or HTTP transfer rates. The denial
of service handling test MUST be run after obtaining baseline
measurements from sections 5.3 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.
5.5.2 Setup Parameters
Use the same setup parameters as defined in section 5.3.2 or 5.6.2,
depending on whether testing against the baseline TCP connection
establishment rate test or HTTP transfer rate test, respectfully.
In addition, the following setup parameters MUST be defined:
SYN attack rate - Rate, expressed in packets per second, at which
the server(s) or NAT proxy address is targeted with TCP SYN packets.
5.5.3 Procedure
Use the same procedure as defined in section 5.3.3 or 5.6.3,
depending on whether testing against the baseline TCP connection
establishment rate or HTTP transfer rate 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 or NAT proxy in response to
the SYN packet.
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 and disabled to determine how well the DUT/SUT
can maintain, under such attacks, the baseline connection
establishment rates and HTTP transfer rates determined in section
5.3 and section 5.6, respectively.
5.5.4 Measurements
Perform the same measurements as defined in section 5.3.4 or 5.6.4,
depending on whether testing against the baseline TCP connection
establishment rate test or HTTP transfer rate, respectfully.
In addition, the tester SHOULD track TCP 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 5.3.5 or 5.6.5, depending on whether testing against the
baseline TCP connection establishment rate test or HTTP transfer
rate, respectfully.
In addition, the report MUST indicate a denial of service handling
test, SYN attack rate, number TCP SYN attack packets transmitted
and the number of TCP SYN attack packets forwarded by the DUT/SUT.
The report MUST indicate whether or not the DUT has any SYN attack
mechanisms enabled.
5.6 HTTP Transfer Rate
5.6.1 Objective
To determine the transfer rate of HTTP requested object transversing
the DUT/SUT.
5.6.2 Setup Parameters
The following parameters MUST be defined for all tests:
5.6.2.1 Transport-Layer Setup Parameters
Number of connections - Defines the aggregate number of
connections attempted. The number SHOULD be a multiple of the
number of virtual clients participating in the test.
Close Method - Defines method for closing TCP connections. The
test MUST be performed with either a three-way or four-way
handshake. In a four-way handshake, each side sends separate FIN
and ACK messages. In a three-way handshake, one side sends a
combined FIN/ACK message upon receipt of a FIN.
Close Direction - Defines whether closing of connections are to
be initiated from the client or from the server.
5.6.2.2 Application-Layer Setup Parameters
Session Type - The virtual clients/servers MUST use HTTP 1.1 or
higher.
GET requests per connection - Defines the number of HTTP 1.1 or
higher GET requests attempted per connection.
Object Size - Defines the number of bytes, excluding any bytes
associated with the HTTP header, to be transferred in response to
an HTTP 1.1 or higher GET request.
5.6.3 Procedure
Each HTTP 1.1 or higher virtual client will request one or more
objects from an HTTP 1.1 or higher server using one or more HTTP
GET requests over each connection. The aggregate number of
connections attempted, defined by number of connections, MUST be
evenly divided among all of the participating virtual clients.
If the virtual client(s) make multiple HTTP GET requests per
connection, it MUST request the same object size for each GET
request. Multiple iterations of this test may be run with objects
of different sizes.
5.6.4 Measurements
5.6.4.1 Application-Layer measurements
Average Transfer Rate - The average transfer rate of the DUT/SUT
MUST be measured and shall be referenced to the requested
object(s). The measurement will start on transmission of the
first bit of the first requested object and end on transmission
of the last bit of the last requested object. The average
transfer rate, in bits per second, will be calculated using the
following formula:
OBJECTS * OBJECTSIZE * 8
TRANSFER RATE(bit/s) = --------------------------
DURATION
OBJECTS - Total number of objects successfully transferred across
all connections.
OBJECTSIZE - Object size in bytes
DURATION - Aggregate transfer time based on aforementioned time
references.
5.6.4.2 Measurements at or below the Transport-Layer
The following measurements SHOULD be performed for each
connection-oriented protocol:
Goodput[1] - Goodput as defined in section 3.17 of RFC2647.
Measurements MUST only reference the protocol payload, excluding
any of the protocol header. In addition, the tester MUST exclude
any bits associated with the connection establishment, connection
tear down, security associations[1] or connection maintenance[1].
Since connection-oriented protocols require that data be
acknowledged, the offered load[6] will be varying. Therefore, the
tester should measure the average forwarding rate over the
duration of the test. Measurement should start on transmission of
the first bit of the payload of the first datagram and end on
transmission of the last bit of the payload of the last datagram.
Number of bytes transferred - Total payload bytes transferred.
Number of Timeouts - Total number of timeout events.
Retransmitted bytes - Total number of retransmitted bytes.
5.6.5 Reporting Format
5.6.5.1 Application-Layer reporting
The test report MUST note number of GET requests per connection
and object size(s).
The transfer rate results SHOULD be reported in tabular form with
a column for each of the object sizes tested. There SHOULD be a
row for the object size, number and percentage of completed
requests, number and percentage of completed responses, and the
resultant transfer rate for each iteration of the test.
Failure analysis:
The test report SHOULD indicate the number and percentage of HTTP
GET request and responses that failed to complete.
Version information:
The test report MUST note the version of HTTP client(s) and
server(s).
5.6.5.2 Transport-Layer and below reporting
The test report MUST note the number of connections, close
method, close direction and the protocol for which the
measurement was made.
The results SHOULD be reported in tabular form for each of the
HTTP object sizes tested. There SHOULD be a row for the HTTP
object size, resultant goodput, total timeouts, total
retransmitted bytes and total bytes transferred. Note that total
bytes refers to total datagram payload bytes transferred. The
table MAY be combined with the application layer reporting,
provided the table clearly identify the protocol for which the
measurement was made.
Failure analysis:
The test report SHOULD indicate the number and percentage of
connection establishment failures as well as number and
percentage of TCP tear down failures.
It is RECOMMENDED that the report include a graph to plot the
distribution of both connection establishment failures and
connection tear down failures. The x coordinate SHOULD be the
elapsed test time, the y coordinate SHOULD be the number of
failures for a given sampling period. There SHOULD be two lines
on the graph, one for connection failures and one for tear down
failures. The graph MUST note the sampling period.
5.7 Maximum HTTP Transaction Rate
5.7.1 Objective
Determine the maximum transaction rate the DUT/SUT can sustain. This
test is intended to find the maximum rate at which users can access
objects.
5.7.2 Setup Parameters
5.7.2.1 Transport-Layer Setup Parameters
Close Method - Defines method for closing TCP connections. The
test MUST be performed with either a three-way or four-way
handshake. In a four-way handshake, each side sends separate FIN
and ACK messages. In a three-way handshake, one side sends a
combined FIN/ACK message upon receipt of a FIN.
Close Direction - Defines whether closing of connections are to
be initiated from the client or from the server.
5.7.2.2 Application-Layer Setup Parameters
Session Type - HTTP 1.1 or higher MUST be used for this test.
Test Duration - Time, expressed in seconds, for which the
virtual client(s) will sustain the attempted GET request rate.
It is RECOMMENDED that the duration be at least 30 seconds.
Requests per connection - Number of object requests per
connection.
Object Size - Defines the number of bytes, excluding any bytes
associated with the HTTP header, to be transferred in response to
an HTTP 1.1 or higher GET request.
5.7.3 Procedure
An iterative search algorithm MAY be used to determine the maximum
transaction rate that the DUT/SUT can sustain.
For each iteration, HTTP 1.1 or higher virtual client(s) will vary
the aggregate GET request rate offered to HTTP 1.1 or higher
server(s). The virtual client(s) will maintain the offered request
rate for the defined test duration.
If the virtual client(s) make multiple HTTP GET requests per
connection, it MUST request the same object size for each GET
request. Multiple tests MAY be performed with different object
sizes.
5.7.4 Measurements
Maximum Transaction Rate - The maximum rate at which all
transactions -- that is all requests/responses cycles -- are
completed.
Transaction Time - The tester SHOULD measure minimum, maximum and
average transaction times. The transaction time will start when the
virtual client issues the GET request and end when the requesting
virtual client receives the last bit of the requested object.
5.7.5 Reporting Format
5.7.5.1 Application-Layer reporting
The test report MUST note the test duration, object size,
requests per connection and the measured minimum, maximum and
average transaction rate.
The intermediate results of the search algorithm MAY be reported
in a table format with a column for each iteration. There SHOULD
be rows for the GET request attempt rate, number of requests
attempted, number and percentage of requests completed, number of
responses attempted, number and percentage of responses
completed, minimum transaction time, average transaction time and
maximum transaction time.
Version information:
The test report MUST note the version of HTTP client(s) and
server(s).
5.7.5.2 Transport-Layer
The test report MUST note the close method, close direction,
number of connections established and number of connections torn
down.
The intermediate results of the search algorithm MAY be reported
in a table format with a column for each iteration. There SHOULD
be rows for the number of connections attempted, number and
percentage of connections completed, number and percentage of
connection tear downs completed. The table MAY be combined with
the application layer reporting, provided the table identify this
as transport layer measurement.
5.8 Illegal Traffic Handling
5.8.1 Objective
To character the behavior of the DUT/SUT when presented with a
combination of both legal and Illegal[1] traffic. Note that Illegal
traffic does not refer to an attack, but traffic which has been
explicitly defined by a rule(s) to drop.
5.8.2 Setup Parameters
Setup parameters will use the same parameters as specified in the
HTTP transfer rate test(Section 5.6.2). In addition, the following
setup parameters MUST be defined:
Illegal traffic percentage - Percentage of HTTP 1.1 or higher
connections which have been explicitly defined in a rule(s) to drop.
5.8.3 Procedure
Each HTTP 1.1 or higher client will request one or more objects from
an HTTP 1.1 or higher server using one or more HTTP GET requests
over each connection. The aggregate number of connections attempted,
defined by number of connections, MUST be evenly divided among all
of the participating virtual clients.
The virtual client(s) MUST offer 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). Multiple iterations of this test MAY
be run with the DUT/SUT configured to filter on different traffic
criteria.
5.8.4 Measurements
The same measurements as defined in HTTP transfer rate test(Section
5.6.4) SHOULD be performed. Any forwarding rate measurements MUST
only include bits which are associated with legal traffic.
5.8.5 Reporting Format
Test reporting format SHOULD be the same as specified in the HTTP
transfer rate test(Section 5.6.5).
In addition, the report MUST note the percentage of illegal HTTP
connections.
Failure analysis:
Test report MUST note the number and percentage of illegal
connections that were allowed by the DUT/SUT.
5.9 IP Fragmentation Handling
5.9.1 Objective
To determine the performance impact when the DUT/SUT is presented
with IP fragmented[5] traffic. IP packets which have been
fragmented, due to crossing a network that supports a smaller
MTU(Maximum Transmission Unit) than the actual IP packet, may
require the firewall to perform re-assembly prior to the rule set
being applied.
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 packets have on the forwarding rate of the
DUT/SUT. RFC 1858 addresses some fragmentation attacks that
get around IP filtering processes used in routers and hosts.
5.9.2 Setup Parameters
The following parameters MUST be defined.
5.9.2.1 Non-Fragmented Traffic Parameters
Setup parameters will be the same as defined in the HTTP transfer
rate test(Sections 5.6.2.1 and 5.6.2.2).
5.9.2.2 Fragmented Traffic Parameters
Packet size - Number of bytes in the IP/UDP packet, exclusive of
link-layer headers and checksums, prior to fragmentation.
MTU - Maximum transmission unit, expressed in bytes. For testing
purposes, this MAY be configured to values smaller than the MTU
supported by the link layer.
Intended Load - Intended load, expressed as percentage of media
utilization.
5.9.3 Procedure
Each HTTP 1.1 or higher client will request one or more objects from
an HTTP 1.1 or higher server using one or more HTTP GET requests
over each connection. The aggregate number of connections attempted,
defined by number of connections, MUST be evenly divided among all
of the participating virtual clients. If the virtual client(s) make
multiple HTTP GET requests per connection, it MUST request the same
object size for each GET request.
A tester attached to the unprotected side of the network, will offer
a unidirectional stream of unicast fragmented IP/UDP traffic,
targeting a server attached to either the protected or DMZ segment.
The tester MUST offer the unidirectional stream over the duration of
the test -- that is, duration over which the HTTP traffic is being
offered.
Baseline measurements SHOULD be performed with IP filtering deny
rule(s) to filter 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 MTU while
keeping all other parameters constant.
Then setup the DUT/SUT to the policy or rule set the manufacturer
required to be defined to protect against fragmentation attacks and
repeat the measurements outlined in the baseline procedures.
5.9.4 Measurements
Tester SHOULD perform the same measurements as defined in HTTP
test(Section 5.6.4).
Transmitted UDP/IP Packets - Number of UDP packets transmitted by
client.
Received UDP/IP Packets - Number of UDP/IP Packets received by
server.
5.9.5 Reporting Format
5.10.1 Non-Fragmented Traffic
The test report SHOULD be the same as described in section 5.6.5.
Note that any forwarding rate measurements for the HTTP traffic
excludes any bits associated with the fragmented traffic which
may be forward by the DUT/SUT.
5.9.2 Fragmented Traffic
The test report MUST note the packet size, MTU size, intended
load, number of UDP/IP packets transmitted and number of UDP/IP
packets forwarded. The test report SHOULD also note whether or
not the DUT/SUT forwarded the offered UDP/IP traffic fragmented.
5.10 Latency
5.10.1 Objective
To determine the latency of network-layer or application-layer data
traversing the DUT/SUT. RFC 1242 [3] defines latency.
5.10.2 Setup Parameters
The following parameters MUST be defined:
5.10.2.1 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.
Test duration, expressed in seconds.
Test instruments MUST generate packets with unique timestamp
signatures.
5.10.2.2 Application-layer Measurements
Object Size - Defines the number of bytes, excluding any bytes
associated with the HTTP header, to be transferred in response to
an HTTP 1.1 or higher 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 or higher
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.
5.10.3 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.
It is RECOMMENDED to perform the latency measurements with
different packet sizes. When testing with different packet sizes
the DUT/SUT configuration MUST remain the same.
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.
5.10.4 Application layer procedure
An HTTP 1.1 or higher client will request one or more objects from
an HTTP 1.1 or higher 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.
5.10.5 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.
5.10.6 Network-layer reporting format
The test report MUST note the packet size(s), offered load(s) and
test duration used.
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.
5.10.7 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 version of HTTP client and server.
6. 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.
[6] Mandeville, R., "Benchmarking Terminology for LAN Switching
Devices", RFC 2285, February 1998.
[7] Mandeville, R., Perser,J., "Benchmarking Methodology for LAN
Switching Devices", RFC 2889, August 2000.
[8] Postel, J. (ed.), "Internet Protocol - DARPA Internet Program
Protocol Specification", RFC 793, USC/Information Sciences
Institute, September 1981.
7. Security Considerations
The primary goal of this document is to provide methodologies in
benchmarking firewall performance. While there is some overlap
between performance and security issues, assessment of firewall
security is outside the scope of this document.
8. Acknowledgement
Funding for the RFC Editor function is currently provided by the
Internet Society.
9. Authors' Addresses
Brooks Hickman
Spirent Communications
26750 Agoura Road
Calabasas, CA 91302
USA
Phone: + 1 818 676 2412
Email: brooks.hickman@spirentcom.com
David Newman
Network Test Inc.
31324 Via Colinas, Suite 113
Westlake Village, CA 91362-6761
USA
Phone: + 1 818 889-0011
Email: dnewman@networktest.com
Saldju Tadjudin
Spirent Communications
26750 Agoura Road
Calabasas, CA 91302
USA
Phone: + 1 818 676 2468
Email: Saldju.Tadjudin@spirentcom.com
Terry Martin
GVNW Consulting Inc.
8050 SW Warm Springs Road
Tualatin Or. 97062
USA
Phone: + 1 503 612 4422
Email: tmartin@gvnw.com
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. While some implementations
HTTP/1.0 supports persistence through the use of a keep-alive,
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.
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. If the DUT/SUT
closes inactive connections, the aging timer on the DUT SHOULD
be configured for a duration that exceeds the test time.
While this document cannot foresee future changes to HTTP
and it 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.
APPENDIX B: Connection Establishment Time Measurements
Some connection oriented protocols, such as TCP, involve an odd
number of messages when establishing a connection. In the case of
proxy based DUT/SUTs, the DUT/SUT will terminate the connection,
setting up a separate connection to the server. Since, in such
cases, the tester does not own both sides of the connection,
measurements will be made two different ways. While the following
describes the measurements with reference to TCP, the methodology
may be used with other connection oriented protocols which involve
an odd number of messages.
When testing non-proxy based DUT/SUTs , the establishment time shall
be directly measured and is considered to be from the time the first
bit of the first 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.
If the DUT/SUT is proxy based, the connection establishment time is
considered to be from the time the first bit of the first SYN packet
is transmitted by the client to the time the client transmits the
first bit of the first acknowledged TCP datagram(t4-t0 in the
following timeline).
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.
APPENDIX C: Connection Tear Time Measurements This memo provides information for the Internet community. It does
not specify an Internet standard of any kind. Distribution of this
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The connection tear down will be considered the interval between the
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by the virtual client or server, whichever is applicable, requesting
a connection tear down to receipt of the last bit of the
corresponding ACK packet on the same virtual client/server interface.
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