Network Working Group E. Abdo
Internet-Draft M. Boucadair
Intended status: Informational J. Queiroz
Expires: May 3, 2012 France Telecom
October 31, 2011
HOST_ID TCP Options: Implementation & Preliminary Test Results
draft-abdo-hostid-tcpopt-implementation-01
Abstract
This memo documents the implementation of the HOST_ID TCP Options.
It also discusses the preliminary results of the tests that have been
conducted to assess the technical feasibility of the approach as well
as its scalability. Several HOST_ID TCP options have been
implemented and tested.
Status of this Memo
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provisions of BCP 78 and BCP 79.
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This Internet-Draft will expire on May 3, 2012.
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Copyright (c) 2011 IETF Trust and the persons identified as the
document authors. All rights reserved.
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described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . 3
3. NAT Reveal TCP Options: Overview . . . . . . . . . . . . . . . 3
3.1. HOST_ID_WING TCP Option . . . . . . . . . . . . . . . . . 4
3.2. HOST_ID_BOUCADAIR TCP Option . . . . . . . . . . . . . . . 4
3.2.1. SYN Mode . . . . . . . . . . . . . . . . . . . . . . . 5
3.2.2. ACK Mode . . . . . . . . . . . . . . . . . . . . . . . 5
4. Overview of the Linux Kernel Modifications . . . . . . . . . . 6
5. Testbed Setup & Configuration . . . . . . . . . . . . . . . . 7
5.1. Automated TCP Traffic Generator . . . . . . . . . . . . . 8
5.2. Testing Methodology and Procedure . . . . . . . . . . . . 9
5.3. Check HOST_ID TCP Options are Correctely Injected . . . . 9
5.4. Top Site List . . . . . . . . . . . . . . . . . . . . . . 10
6. Experimentation Results . . . . . . . . . . . . . . . . . . . 10
6.1. HTTP Experimentation Results . . . . . . . . . . . . . . . 10
6.1.1. Proxy . . . . . . . . . . . . . . . . . . . . . . . . 14
6.1.2. Anomalies . . . . . . . . . . . . . . . . . . . . . . 14
6.1.3. CPEs Behaviour . . . . . . . . . . . . . . . . . . . . 16
6.2. FTP . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
6.3. SSH . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
6.4. Telnet . . . . . . . . . . . . . . . . . . . . . . . . . . 18
7. Next Steps . . . . . . . . . . . . . . . . . . . . . . . . . . 18
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 18
9. Security Considerations . . . . . . . . . . . . . . . . . . . 18
10. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 18
11. References . . . . . . . . . . . . . . . . . . . . . . . . . . 19
11.1. Normative References . . . . . . . . . . . . . . . . . . . 19
11.2. Informative References . . . . . . . . . . . . . . . . . . 19
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 19
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1. Introduction
To ensure IPv4 service continuity, service providers will need to
deploy IPv4 address sharing techniques. Several issues are likely to
be encountered (refer to [RFC6269] for a detailed survey of the
issues) and they may affect the delivery of services that depends on
the enforcement of policies based upon the source IPv4 address.
Some of these issues may be mitigated owing to the activation of
advanced features. Among the solutions analyzed in
[I-D.boucadair-intarea-nat-reveal-analysis], the use of a new TCP
option to convey a HOST_ID seems to be a promising solution.
This memo documents some implementation and experimentation efforts
that have been conducted to assess the viability of using Host_ID TCP
options at large scale. In particular, this document provides
experimentation results related to the support of the HOST_ID TCP
Options, the behavior of legacy TCP servers when receiving the
HOST_ID TCP option. This draft also discusses the impact of using a
Host_ID TCP option on the time it takes to establish a connection.
2. Objectives
The implementation of several HOST_ID TCP options is primarily meant
to:
o Assess the validity of the HOST_ID TCP option approach
o Evaluate the impact on a TCP stack to support the HOST_ID TCP
options
o Improve filtering and logging capabilities based upon the contents
of the HOST_ID TCP option. This means the enforcement of various
policies based upon the content of the HOST_ID TCP option at the
server side: Log, Deny, Accept, etc.
o Assess the behavior of legacy TCP servers when receiving a HOST_ID
TCP option
o Assess the success ratio of TCP communications when a HOST_ID TCP
option is received
o Assess the impact of injecting a HOST_ID TCP option on the time it
takes to establish a connection
o Assess the performance impact on the CGN device that has been
configured to inject the HOST_ID option
3. NAT Reveal TCP Options: Overview
The original idea of defining a TCP option is documented in
[I-D.wing-nat-reveal-option] (denoted as HOST_ID_WING).
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An additional TCP option format to convey a HOST_ID has been also
considered (denoted as HOST_ID_BOUCADAIR). The main motivation is to
cover also the load-balancer use case and provide richer
functionality as Forwarded-For HTTP header
[I-D.petersson-forwarded-for].
The following sub-sections provide an overview of these HOST_ID TCP
options.
3.1. HOST_ID_WING TCP Option
HOST_ID_WING is defined in [I-D.wing-nat-reveal-option]. Figure 1
shows the format of this option.
+--------+--------+-----------------------+
|Kind=TBD|Length=4| USER_ID Data |
+--------+--------+-----------------------+
Figure 1: Format of HOST_ID_WING TCP Option
Figure 2 shows an example of using HOST_ID_WING TCP option.
+------------+ +------------+ +------------+
| TCP CLIENT | | CGN | | TCP SERVER |
+------------+ +------------+ +------------+
| | |
|---TCP SYN---------->| |
| |---TCP SYN, HOST_ID=12345---->|
| | |
Figure 2: HOST_ID_WING TCP Option: Flow example
3.2. HOST_ID_BOUCADAIR TCP Option
As mentioned above, the HOST_ID_BOUCADAIR TCP Option is inspired form
HOST_ID_WING and XFF. Figure 3 shows the format of HOST_ID_BOUCADAIR
TCP Option.
+--------+---------+---+---+--------..-------+
|Kind=TBD|Length=10| L | O |HOST_ID data | HOST_ID
+--------+---------+---+---+--------..-------+
Figure 3: Format of HOST_ID_BOUCADAIR TCP option
o L: Indicates the validity lifetime of the enclosed data (in the
spirit of [RFC6250]). The following values are supported:
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0: Permanent;
>0:Dynamic; this value indicates the validity time.
o Origin: Indicates the origin of the data conveyed in the data
field. The following values are supported:
0: Internal Port
1: Internal IPv4 address
2: Internal Port: Internal IPv4 address
3: IPv6 Prefix
>3: No particular semantic
o HOST_ID: depends on the content of the Origin field; padding is
required.
Two modes are described below: the SYN mode (Section 3.2.1) and the
ACK mode. (Section 3.2.2).
If the ACK mode is used (Section 3.2.2), Figure 4 shows the
HOST_ID_ENABLED option to be included in the SYN.
+--------+---------+
|Kind=TBD|Length=2 | HOST_ID_ENABLED
+--------+---------+
Figure 4: Format of HOST_ID_ENABLED
3.2.1. SYN Mode
This mode is similar to Section 3.1. In this mode, HOST_ID_BOUCADAIR
is sent in SYN packets.
+------------+ +------------+ +------------+
| TCP CLIENT | | CGN | | TCP SERVER |
+------------+ +------------+ +------------+
| | |
|---TCP SYN-------->| |
| |--TCP SYN, HOST_ID=2001:db8::/5482->|
| | |
Figure 5: HOST_ID_BOUCADAIR: SYN Mode
3.2.2. ACK Mode
The ACK Mode is as follows (see Figure 6):
o Send HOST_ID_ENABLED (Figure 4) in SYN
o If the remote TCP server supports that option, it must return it
in SYNACK
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o Then the TCP Client sends HOST_ID_BOUCADAIR (Figure 3) in ACK
+------------+ +------------+ +------------+
| TCP CLIENT | | CGN | | TCP SERVER |
+------------+ +------------+ +------------+
| | |
|---TCP SYN---------->| |
| |--TCP SYN, HOSTID_ENABLED=OK-->|
| |<-TCP SYNACK,HOSTID_ENABLED=OK-|
|<--TCP SYNACK--------| |
|---TCP ACK---------->| |
| |--TCP ACK, USER_ID=2001:db8::->|
| | |
Figure 6
4. Overview of the Linux Kernel Modifications
At this stage, only the SYN mode has been implemented for both
HOST_ID_WING and HOST_ID_BOUCADAIR TCP options.
In order to support the injection of the HOST_ID TCP options
presented in Section 3, some modifications were applied to the Linux
Kernel (more precisely to the TCP stack). Major modifications have
been made in the tcp_output.c file (file responsible for building and
transmitting all TCP packets). New variables have been defined and
functions manipulating the TCP options in SYN packets have been
modified to inject the configured TCP option in the corresponding SYN
packet.
Since different options can be injected, they have to be easily
configurable. System control variables (a.k.a., sysctl variables)
are defined for this purpose.
The Kernel must be recompiled so that the new TCP options are taken
into account.
Kernel modifications and recompilation have been done and tested
successfully on Fedora and Debian Linux distributions, on different
kernel versions.
The following configuration options are supported:
o Enable/Disable injecting the TCP Option
o Support HOST_ID WING and HOST_ID BOUCADAIR
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o When the HOST_ID TCP option is supported, the information to be
injected is configurable:
* Source IPv6 address or the first 64 bits of the address
* Source IPv4 address
* Source port number
* Source IPv4 address and Source port
* IPv6 address or the first 64 bits of the B4 when DS-Lite is
activated
o When the HOST_ID TCP option is enabled, stripping any existing
HOST_ID TCP option is enabled by default.
5. Testbed Setup & Configuration
The setup of three testbed configurations have been considered:
1. HOST_ID TCP option is injected by the host itself. No CGN is
present in the communication path (Figure 7)
2. HOST_ID TCP option is injected by hosts deployed behind a HTTP
proxy. No CGN is present in the communication path (Figure 8)
3. HOST_ID TCP option is injected by the DS-Lite AFTR element
(Figure 9).
+-----------+
| HOST_1 |----+
| NO-Option | |
+-----------+ | +--------------------+ +------------+
| | |--------| server 1 |
+-----------+ | | | +------------+
| HOST_2 |----|------| INTERNET | ::
| (HOST_ID) | | | | +------------+
+-----------+ | | |--------| server n |
| +--------------------+ +------------+
+-----------+ |
| Local |----+
| Server |
+-----------+
Figure 7: Testbed setup: No Proxy and no CGN
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+-----------+
| HOST_1 |----+
| NO-Option | |
+-----------+ | +--------------------+ +------------+
| | |------| server 1 |
+-----------+ +-----+ | | +------------+
| HOST_2 |--|PROXY|----| INTERNET | ::
| (HOST_ID) | +-----+ | | | +------------+
+-----------+ | | |------| server n |
| +--------------------+ +------------+
+-----------+ |
| Local |-----------+
| Server |
+-----------+
Figure 8: Testbed setup: HTTP Proxy
+----...----+ +----------+
+----+ | | | |---| server 1 |
|HOST|---| +----+ | +------+ | | | +----------+
+----+ |--| B4 |---|---| AFTR |---|---| INTERNET | ::
+----+ | +------+ | | | +----------+
| | |---| server n |
+----...----+ +----------+
Figure 9: DS-Lite CGN Environment
Figure 7 and Figure 8 are used to assess the behavior of the top 1000
sites when a HOST_ID option is enabled and to evaluate the impact of
the option on both the session establishment delay and the success
ratio.
On the other hand, the configuration shown in Figure 9 will be used
to evaluate the impact on the CGN performances when HOST_ID TCP
option is injected by the CGN.
5.1. Automated TCP Traffic Generator
A Python-coded robot has been used as the traffic generator. The
robot automates the retrieval of HTTP pages identified by URLs, and
returns different connection information. The web pages retrieval is
based on Pycurl, a Python interface of libcurl. Libcurl is an URL
transfer library that supports different protocols (e.g., HTTP, FTP).
The robot consists of two programs:
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1. The first one takes an URL as a input parameter, performs the DNS
lookup and then tries to connect to the corresponding machine.
It returns either different time values and connection status or
an error message with the source of the error in case of
connection failure (e.g., DNS error). The TCP connection
establishment time is calculated as the difference between the
CONNECT_TIME and NAMELOOKUP_TIME where:
* NAMELOOKUP_TIME is the time it took from the start until the
name resolution is completed.
* CONNECT_TIME is the time it took from the start until the
connection to the remote host (or proxy) is completed.
2. The second program aims to increase efficiency and speed of the
testing by using a multi-thread technique. It takes the number
of threads and an input file listing URLs as parameters. This
program prints URLs to an output file with the corresponding
connection time. If something wrong happened so that the
connection failed, the program returns an error message with the
corresponding error type.
5.2. Testing Methodology and Procedure
The testing is done using two machines, one that supports the HOST_ID
TCP options and the other that does not. The second machine is used
as a reference for the measurements. Testing is performed in
parallel on the two machines that are directly connected to the
Internet. For each HOST_ID TCP option, the test is performed 10
times. The cycle is repeated in different days. Then results are
grouped into tables where averages are calculated. The comparison
between the different HOST_ID options results is made by using the
no-option testing results as a reference.
Testing was also performed behind a proxy (Figure 8) to evaluate the
impact of embedding the HOST_ID TCP options on the connection
establishment time when a proxy is in the path. When a proxy is
present, the connection delay is impacted.
Tests have been conducted from hosts:
1. Connected to two (2) commercial ISP networks
2. Connected to an enterprise network
3. In a lab behind a firewall
5.3. Check HOST_ID TCP Options are Correctely Injected
To check whether the HOST_ID TCP options are correctly injected, the
local server in Figure 7 is configured to be reachable from Internet.
Packets conveying the HOST_ID TCP options are sent from a host
supporting the options. These packets are used without alteration by
the local server.
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This configuration confirms the packets sent to remote servers
conveys HOST_ID TCP options.
5.4. Top Site List
The Alexa top sites list has been used to conduct the HTTP tests.
Anonymous FTP sites list from ftp-sites.org has been used to conduct
the FTP tests.
6. Experimentation Results
6.1. HTTP Experimentation Results
Various combinations of the HOST_ID TCP options have been tested:
1. HOST_ID_WING
HOST_ID_WING has also been adapted to include 32 bits and 64
bits values. No particular impact on session establishment
has been observed.
2. HOST_ID_BOUCADAIR (source port)
3. HOST_ID_BOUCADAIR (IPv4 address)
4. HOST_ID_BOUCADAIR (source port:IPv4 address)
5. HOST_ID_BOUCADAIR (IPv6 Prefix)
Both the success ratio and the average time to establish the TCP
session are reported below.
The results show that the success ratio for establishing TCP
connection with legacy servers, is almost the same for all the
HOST_ID options Figure 10 Figure 11 and Figure 12.
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+-----------+-----------+--------------+
| NO_OPTION | WING | Failure Ratio|
---------+-----------+-----------+--------------+
Top10 |100,00000% |100,00000% | 0,00000% |
Top100 |100,00000% |100,00000% | 0,00000% |
Top200 |100,00000% |100,00000% | 0,00000% |
Top300 | 99,66667% | 99,66667% | 0,00000% |
Top400 | 99,50000% | 99,50000% | 0,00000% |
Top500 | 99,40000% | 99,40000% | 0,00000% |
Top600 | 99,33333% | 99,33333% | 0,00000% |
Top700 | 99,42857% | 99,42857% | 0,00000% |
Top800 | 99,37500% | 99,37500% | 0,00000% |
Top900 | 99,33333% | 99,33333% | 0,00000% |
Top1000 | 99,40000% | 99,40000% | 0,00000% |
Top2000 | 99,25000% | 99,20000% | 0,05000% |
Top3000 | 99,13333% | 99,10000% | 0,03333% |
Top4000 | 99,10000% | 99,05000% | 0,05000% |
Top5000 | 99,08000% | 99,04000% | 0,04000% |
Top6000 | 99,18333% | 99,15000% | 0,03333% |
Top7000 | 99,21429% | 99,15714% | 0,05714% |
Top8000 | 99,11250% | 99,05000% | 0,06250% |
Top9000 | 99,11111% | 99,05556% | 0,05556% |
Top10000 | 99,12000% | 99,07000% | 0,05000% |
---------+-----------+-----------+--------------+
Figure 10: Cumulated Success Ratio (HOST_ID_WING)
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+------+-------+--------------+
| NOP | WING | Failure Ratio|
----------+------+-------+--------------+
1-100 | 100% | 100% | 0,00% |
101-200 | 100% | 100% | 0,00% |
201-300 | 100% | 100% | 0,00% |
301-400 | 99% | 99% | 0,00% |
401-500 | 100% | 100% | 0,00% |
501-600 | 100% | 100% | 0,00% |
601-700 | 100% | 100% | 0,00% |
701-800 | 99% | 99% | 0,00% |
801-900 | 99% | 99% | 0,00% |
901-1000 | 100% | 100% | 0,00% |
0-1000 |99,4% | 99,4% | 0,00% |
1001-2000 |99,1% | 99,0% | 0,10% |
2001-3000 |98,9% | 98,9% | 0,00% |
3001-4000 |99,0% | 98,9% | 0,10% |
4001-5000 |99,0% | 99,0% | 0,00% |
5001-6000 |99,7% | 99,7% | 0,00% |
6001-7000 |99,4% | 99,2% | 0,20% |
7001-8000 |98,4% | 98,3% | 0,10% |
8001-9000 |99,1% | 99,1% | 0,00% |
9001-10000|99,3% | 99,3% | 0,00% |
----------+------+-------+--------------+
Figure 11: TopX000 Success Ratio (HOST_ID_WING)
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+------+-------+--------------+
| NOP | OB | Failure Ratio|
----------+------+-------+--------------+
1-100 | 100% | 100% | 0,00% |
101-200 | 100% | 100% | 0,00% |
201-300 | 100% | 100% | 0,00% |
301-400 | 99% | 99% | 0,00% |
401-500 | 100% | 100% | 0,00% |
501-600 | 100% | 100% | 0,00% |
601-700 | 100% | 100% | 0,00% |
701-800 | 99% | 99% | 0,00% |
801-900 | 99% | 99% | 0,00% |
901-1000 | 100% | 100% | 0,00% |
0-1000 |99,4% | 99,4% | 0,00% |
1001-2000 |99,1% | 99,0% | 0,10% |
2001-3000 |98,9% | 98,9% | 0,00% |
3001-4000 |99,0% | 98,9% | 0,10% |
4001-5000 |99,0% | 99,0% | 0,00% |
5001-6000 |99,7% | 99,7% | 0,00% |
6001-7000 |99,4% | 99,2% | 0,20% |
7001-8000 |98,4% | 98,3% | 0,10% |
8001-9000 |99,1% | 99,0% | 0,10% |
9001-10000|99,3% | 99,3% | 0,00% |
----------+------+-------+--------------+
Figure 12: TopX000 Success Ratio (HOST_ID_BOUCADAIR)
+------+-----------+---------------+
| NOP | OPT_WING | OPT_BOUCADAIR |
------------+------+-----------+---------------+
Timeout | 44 | 48 | 49 |
------------+------+-----------+---------------+
DNS Failure | 26 | 26 | 26 |
------------+------+-----------+---------------+
Figure 13: Failure Distribution
The above tables (Figure 10Figure 11 and Figure 12) show that only
very few servers are impacted by the injection of the HOST_ID option.
For the top10000, the main cause of failure is DNS (see Figure 13)
For the Top10000 websites, 5 servers do not reply when a HOST_ID TCP
option is included:
www.barclays.co.uk
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www.carrefour.fr
www.morguefile.com
www.gamespress.com
www.mymovies.it
When HOST_ID_BOUCADAIR is used, an additional server does not reply:
www.lawyers.com
These results show that including a HOST_ID TCP option does not
systematically imply an extra delay for the establishment of the TCP
session. Based upon the average of the session establishment with
the top10000 sites, the following results have been obtained:
o delay(HOST_ID_WING) < delay(NO_OPTION): 47,85 %
o delay(HOST_ID_BOUCADAIR (source port:IPv4 address)) <
delay(NO_OPTION): 47,06 %
o delay(HOST_ID_BOUCADAIR (source port)) < delay(NO_OPTION): 54,9 %
6.1.1. Proxy
When a HTTP proxy is in the path, the injection of HSOT_ID TCP option
does not impact the success ratio. This is because the HTTP proxy
strips the HOST_ID TCP options; these options are not leaked to
remote Internet servers.
6.1.2. Anomalies
Tests have been conducted from hosts:
1. Connected to two commercial ISP networks (using two CPEs each
connected to an ISP network)
2. Connected to an enterprise network
3. In a lab behind a firewall
The results for HOST_ID_WING for all three configurations are the
same as Section 6. Surprisingly, results obtained for
HOST_ID_BOUCADAIR are not the same. Indeed, (1) and (2)
configurations lead to the results documented in Section 6 but
failures have been observed for configuration (3). Figure 14 and
Figure 15 shows the observed results. Note that failures are
encountered for the same set of servers.
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+-----------+-----------+--------------+
| NOB | OB | Failure Ratio|
--------+-----------+-----------+--------------+
Top10 |100,00000% |100,00000% | 0,00000% |
Top100 |100,00000% |100,00000% | 0,00000% |
Top200 |100,00000% |100,00000% | 0,00000% |
Top300 |100,00000% | 99,66667% | 0,33333% |
Top400 | 99,75000% | 99,00000% | 0,75000% |
Top500 | 99,80000% | 99,00000% | 0,80000% |
Top600 | 99,83333% | 98,66667% | 1,16667% |
Top700 | 99,85714% | 98,14286% | 1,71429% |
Top800 | 99,75000% | 98,00000% | 1,75000% |
Top900 | 99.66667% | 97,33333% | 2,33333% |
Top1000 | 99,70000% | 97,10000% | 2,60000% |
-------+-----------+------------+--------------+
Figure 14: Cumulated success ratio
+------+-------+--------------+
| NOB |HOST_ID| Failure Ratio|
--------+------+-------+--------------+
1-100 | 100% | 100% | 0,00% |
101-200 | 100% | 100% | 0,00% |
201-300 | 100% | 99% | 1,00% |
301-400 | 99% | 97% | 2,00% |
401-500 | 100% | 99% | 1,00% |
501-600 | 100% | 97% | 3,00% |
601-700 | 100% | 95% | 5,00% |
701-800 | 99% | 97% | 2,00% |
801-900 | 99% | 92% | 7,00% |
901-1000| 100% | 95% | 5,00% |
--------+------+-------+--------------+
Total | 997 | 971 | 2,60% |
--------+--------------+--------------+
Figure 15: TopX00 Success Ratio
After investigation, it has been concluded that the failure cause is
due to padding bits Section 3.2. Indeed, if the padding is encoded
as a prefix, failures are observed. These failures are not observed
when the padding bits are encoded as a suffix. The main conclusions
of this testing shows that:
2,6% of servers which do not support the HOST_ID TCP option
proceed to some parsing validation.
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6.1.3. CPEs Behaviour
Tests have been also conducted behind two branded CPEs connected to
distinct ISP networks. The main conclusions of these tests are:
1. One commercial CPE discard all connections when HOST_ID_BOUCADAIR
option is conveyed. This CPE proceeds to some parsing function
before relaying TCP packets to Internet.
2. For the second CPE, the same results (for the first top1000) as
Section 6.1 have been obtained even with the padding encoded as a
suffix.
3. After modifying the implementation (Section 4), the same results
(for the first top1000) as Section 6.1 have been obtained for
both branded CPEs.
6.2. FTP
Various combinations of the HOST_ID TCP options have been tested:
1. HOST_ID_WING
2. HOST_ID_BOUCADAIR (source port)
3. HOST_ID_BOUCADAIR (source port:IPv4 address)
A list of 5591 FTP servers has been used to conduct these testings.
Among this list, only 2050 was reachable:
o Failure to reach 937 FTP servers due to connection timeout.
o Failure to reach 1286 FTP servers due to DNS errors.
o Failure to reach 717 FTP servers because access was denied.
o Could not connect to 500 FTP servers
o Etc.
5 errors are experienced to reach the 2050 FTP servers with/without
HOST_ID TCP options (connection timeout). When HOST_ID TCP options
are injected, 9 errors are observed (connection timeout).
Figure 16 and Figure 17 provides more data about the error
distribution.
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+-----------+-----------+--------------+
| NOB | HOST_ID | Failure Ratio|
---------+-----------+-----------+--------------+
1-100 | 100% | 100% | 0,00000% |
101-200 | 100% | 99% | 1,00000% |
201-300 | 100% | 99% | 1,00000% |
301-400 | 99% | 99% | 0,00000% |
401-500 | 100% | 100% | 0,00000% |
501-600 | 100% | 100% | 0,00000% |
601-700 | 99% | 99% | 0,00000% |
701-800 | 100% | 100% | 0,00000% |
801-900 | 100% | 99% | 1,00000% |
901-1000 | 100% | 99% | 1,00000% |
1001-2000| 99,7% | 99,2% | 0,50000% |
2000-2050| 100% | 100% | 0,00000% |
---------+-----------+-----------+--------------+
Figure 16: Cumulated Success Ratio (FTP)
+-----------+-----------+--------------+
| NOB | HOST_ID | Failure Ratio|
----------+-----------+-----------+--------------+
first 10 | 100,0000% | 100,00000%| 0,00000% |
first 100 | 100,0000% | 100,00000%| 0,00000% |
first 200 | 100,0000% | 99,50000% | 0,50000% |
first 300 | 100,0000% | 99,33333% | 0,66667% |
first 400 | 99,75000% | 99,25000% | 0,50000% |
first 500 | 99,80000% | 99,40000% | 0,40000% |
first 600 | 99,83333% | 99,50000% | 0,33333% |
first 700 | 99,71429% | 99,42857% | 0,28571% |
first 800 | 99,75000% | 99,50000% | 0,25000% |
first 900 | 99,77778% | 99,44444% | 0,33333% |
first 1000| 99,80000% | 99,40000% | 0,40000% |
first 2000| 99,75000% | 99,30000% | 0,45000% |
first 2050| 99,75610% | 99,31707% | 0,43902% |
----------+-----------+-----------+--------------+
Figure 17: FirstXXX FTP Servers
The results show that including a HOST_ID TCP option does not
systematically imply an extra delay for the establishment of the TCP
session with remote FTP servers. Based upon the average of the
session establishment with the top10000 sites, the following results
have been obtained:
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o delay(HOST_ID_WING) < delay(NO_OPTION): 48,43902 %
o delay(HOST_ID_BOUCADAIR (source port:IPv4 address)) <
delay(NO_OPTION): 47,41463 %
o delay(HOST_ID_BOUCADAIR (source port)) < delay(NO_OPTION):
48,43902 %
6.3. SSH
The secure shell service has been tested between a host and a ssh
server located in the same network.
SSH connections have been successfully established with the server
for all the HOST_ID TCP options.
6.4. Telnet
Telnet sessions have been successfully initiated for all HOST_ID TCP
options with a server (the CGN used in Figure 9).
7. Next Steps
o Support the HOST_ID Injection in ACK mode
o Support TCP options injection by the CGN and drive the appropriate
testing to conclude about impact of using these options on the CGN
performances
o Update the iptables module to enforce policies based upon the
content of the HOST_ID TCP option
o Test for top1million websites
8. IANA Considerations
This document makes no request of IANA.
9. Security Considerations
Security considerations discussed in [I-D.wing-nat-reveal-option]
should be taken into account.
10. Acknowledgments
Many thanks to M. Meulle, P. Ng Tung and L. Valeyre for their help
and review. Special thanks to C. Jacquenet for his careful review
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and to D. Wing for providing a pointer to FTP sites list.
11. References
11.1. Normative References
[I-D.wing-nat-reveal-option]
Yourtchenko, A. and D. Wing, "Revealing hosts sharing an
IP address using TCP option",
draft-wing-nat-reveal-option-02 (work in progress),
June 2011.
[RFC6250] Thaler, D., "Evolution of the IP Model", RFC 6250,
May 2011.
11.2. Informative References
[I-D.boucadair-intarea-nat-reveal-analysis]
Boucadair, M., Touch, J., Levis, P., and R. Penno,
"Analysis of Solution Candidates to Reveal a Host
Identifier in Shared Address Deployments",
draft-boucadair-intarea-nat-reveal-analysis-04 (work in
progress), September 2011.
[]
Petersson, A. and M. Nilsson, "Forwarded HTTP Extension",
draft-petersson-forwarded-for-01 (work in progress),
October 2011.
[RFC6269] Ford, M., Boucadair, M., Durand, A., Levis, P., and P.
Roberts, "Issues with IP Address Sharing", RFC 6269,
June 2011.
Authors' Addresses
Elie Abdo
France Telecom
Issy Les Moulineaux
Email: elie.abdo@orange.com
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Mohamed Boucadair
France Telecom
Email: mohamed.boucadair@orange.com
Jaqueline Queiroz
France Telecom
Issy Les Moulineaux
Email: jaqueline.queiroz@orange.com
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