Security implications arising from the non-modification of protocol header fields by Network Address Translators (NATs)
draft-gont-behave-nat-security-00.txt

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Abstract

This document analizes the security implications arising from the non-modification of some TCP and IP protocol header fields by Network Address Translators (NATs).

Table of Contents

1.  Introduction
2.  Internet Protocol version 4 (IPv4) header fields
    2.1.  Version
    2.2.  IHL
    2.3.  Type of Service
    2.4.  Total Length
    2.5.  Identification
    2.6.  Flags
    2.7.  Fragment Offset
    2.8.  Time to Live
    2.9.  Protocol
    2.10.  Header Checksum
    2.11.  Source Address
    2.12.  Destination Address
    2.13.  Options
    2.14.  Padding
3.  Transmission Control Protocol (TCP) header fields
    3.1.  Source Port
    3.2.  Destination Port
    3.3.  Sequence Number
    3.4.  Acknowledgment Number
    3.5.  Data Offset
    3.6.  Reserved
    3.7.  Flags
    3.8.  Window
    3.9.  Checksum
    3.10.  Urgent Pointer
    3.11.  Options
    3.12.  Padding
4.  Security Considerations
5.  IANA Considerations
6.  Acknowledgements
7.  References
    7.1.  Normative References
    7.2.  Informative References
§  Author's Address
§  Intellectual Property and Copyright Statements

1.  Introduction

This document analizes the security implications arising from the non-modification of some TCP and IP protocol header fields by Network Address Translators (NATs).

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 [RFC2119] (Bradner, S., “Key words for use in RFCs to Indicate Requirement Levels,” March 1997.).

2.  Internet Protocol version 4 (IPv4) header fields

2.1.  Version

2.2.  IHL

2.3.  Type of Service

2.4.  Total Length

2.5.  Identification

2.6.  Flags

2.7.  Fragment Offset

2.8.  Time to Live

2.9.  Protocol

2.10.  Header Checksum

2.11.  Source Address

2.12.  Destination Address

2.13.  Options

2.14.  Padding

3.  Transmission Control Protocol (TCP) header fields

3.1.  Source Port

3.2.  Destination Port

3.3.  Sequence Number

3.4.  Acknowledgment Number

3.5.  Data Offset

3.6.  Reserved

3.7.  Flags

3.8.  Window

3.9.  Checksum

3.10.  Urgent Pointer

3.11.  Options

3.12.  Padding

4.  Security Considerations

5.  IANA Considerations

This document has no actions for IANA.

6.  Acknowledgements

7.  References

7.1. Normative References

7.2. Informative References

Author's Address

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