Internet Engineering Task Force (IETF) C. Huitema
Request for Comments: 7844 Microsoft
Category: Standards Track T. Mrugalski
ISSN: 2070-1721 ISC
S. Krishnan
Ericsson
May 2016
Internet Engineering Task Force (IETF) C. Huitema
Request for Comments: 7844 Microsoft
Category: Standards Track T. Mrugalski
ISSN: 2070-1721 ISC
S. Krishnan
Ericsson
May 2016
Anonymity Profiles for DHCP Clients
DHCP客户端的匿名配置文件
Abstract
摘要
Some DHCP options carry unique identifiers. These identifiers can enable device tracking even if the device administrator takes care of randomizing other potential identifications like link-layer addresses or IPv6 addresses. The anonymity profiles are designed for clients that wish to remain anonymous to the visited network. The profiles provide guidelines on the composition of DHCP or DHCPv6 messages, designed to minimize disclosure of identifying information.
有些DHCP选项带有唯一标识符。即使设备管理员负责将其他潜在标识（如链路层地址或IPv6地址）随机化，这些标识符也可以启用设备跟踪。匿名配置文件是为希望对访问的网络保持匿名的客户端设计的。配置文件提供了有关DHCP或DHCPv6消息组成的指南，旨在最大限度地减少识别信息的泄露。
Status of This Memo
关于下段备忘
This is an Internet Standards Track document.
这是一份互联网标准跟踪文件。
This document is a product of the Internet Engineering Task Force (IETF). It represents the consensus of the IETF community. It has received public review and has been approved for publication by the Internet Engineering Steering Group (IESG). Further information on Internet Standards is available in Section 2 of RFC 5741.
本文件是互联网工程任务组（IETF）的产品。它代表了IETF社区的共识。它已经接受了公众审查，并已被互联网工程指导小组（IESG）批准出版。有关互联网标准的更多信息，请参见RFC 5741第2节。
Information about the current status of this document, any errata, and how to provide feedback on it may be obtained at http://www.rfc-editor.org/info/rfc7844.
有关本文件当前状态、任何勘误表以及如何提供反馈的信息，请访问http://www.rfc-editor.org/info/rfc7844.
Copyright Notice
版权公告
Copyright (c) 2016 IETF Trust and the persons identified as the document authors. All rights reserved.
版权所有（c）2016 IETF信托基金和确定为文件作者的人员。版权所有。
This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License.
本文件受BCP 78和IETF信托有关IETF文件的法律规定的约束(http://trustee.ietf.org/license-info)自本文件出版之日起生效。请仔细阅读这些文件，因为它们描述了您对本文件的权利和限制。从本文件中提取的代码组件必须包括信托法律条款第4.e节中所述的简化BSD许可证文本，并提供简化BSD许可证中所述的无担保。
Table of Contents
目录
1. Introduction ....................................................4
1.1. Requirements ...............................................4
2. Application Domain ..............................................4
2.1. MAC Address Randomization Hypotheses .......................5
2.2. MAC Address Randomization and DHCP .........................6
2.3. Radio Fingerprinting .......................................6
2.4. Operating System Fingerprinting ............................7
2.5. No Anonymity Profile Identification ........................7
2.6. Using the Anonymity Profiles ...............................8
2.7. What about privacy for DHCP servers? .......................9
3. Anonymity Profile for DHCPv4 ....................................9
3.1. Avoiding Fingerprinting ...................................10
3.2. Client IP Address Field ...................................10
3.3. Requested IP Address Option ...............................11
3.4. Client Hardware Address Field .............................12
3.5. Client Identifier Option ..................................12
3.6. Parameter Request List Option .............................13
3.7. Host Name Option ..........................................13
3.8. Client FQDN Option ........................................14
3.9. UUID/GUID-Based Client Machine Identifier Option ..........15
3.10. User and Vendor Class DHCP Options .......................15
4. Anonymity Profile for DHCPv6 ...................................15
4.1. Avoiding Fingerprinting ...................................16
4.2. Do not send Confirm messages, unless really sure about
the location ..............................................17
4.3. Client Identifier DHCPv6 Option ...........................17
4.3.1. Anonymous Information-request ......................18
4.4. Server Identifier Option ..................................18
4.5. Address Assignment Options ................................18
4.5.1. Obtain Temporary Addresses .........................19
4.5.2. Prefix Delegation ..................................20
4.6. Option Request Option .....................................20
4.6.1. Previous Option Values .............................20
4.7. Authentication Option .....................................21
4.8. User and Vendor Class DHCPv6 Options ......................21
4.9. Client FQDN DHCPv6 Option .................................21
5. Operational Considerations .....................................21
6. Security Considerations ........................................22
7. References .....................................................22
7.1. Normative References ......................................22
7.2. Informative References ....................................23
Acknowledgments ...................................................26
Authors' Addresses ................................................26
1. Introduction ....................................................4
1.1. Requirements ...............................................4
2. Application Domain ..............................................4
2.1. MAC Address Randomization Hypotheses .......................5
2.2. MAC Address Randomization and DHCP .........................6
2.3. Radio Fingerprinting .......................................6
2.4. Operating System Fingerprinting ............................7
2.5. No Anonymity Profile Identification ........................7
2.6. Using the Anonymity Profiles ...............................8
2.7. What about privacy for DHCP servers? .......................9
3. Anonymity Profile for DHCPv4 ....................................9
3.1. Avoiding Fingerprinting ...................................10
3.2. Client IP Address Field ...................................10
3.3. Requested IP Address Option ...............................11
3.4. Client Hardware Address Field .............................12
3.5. Client Identifier Option ..................................12
3.6. Parameter Request List Option .............................13
3.7. Host Name Option ..........................................13
3.8. Client FQDN Option ........................................14
3.9. UUID/GUID-Based Client Machine Identifier Option ..........15
3.10. User and Vendor Class DHCP Options .......................15
4. Anonymity Profile for DHCPv6 ...................................15
4.1. Avoiding Fingerprinting ...................................16
4.2. Do not send Confirm messages, unless really sure about
the location ..............................................17
4.3. Client Identifier DHCPv6 Option ...........................17
4.3.1. Anonymous Information-request ......................18
4.4. Server Identifier Option ..................................18
4.5. Address Assignment Options ................................18
4.5.1. Obtain Temporary Addresses .........................19
4.5.2. Prefix Delegation ..................................20
4.6. Option Request Option .....................................20
4.6.1. Previous Option Values .............................20
4.7. Authentication Option .....................................21
4.8. User and Vendor Class DHCPv6 Options ......................21
4.9. Client FQDN DHCPv6 Option .................................21
5. Operational Considerations .....................................21
6. Security Considerations ........................................22
7. References .....................................................22
7.1. Normative References ......................................22
7.2. Informative References ....................................23
Acknowledgments ...................................................26
Authors' Addresses ................................................26
There have been reports of systems that would monitor the wireless connections of passengers at Canadian airports [CNBC]. We can assume that these are either fragments or trial runs of a wider system that would attempt to monitor Internet users as they roam through wireless access points and other temporary network attachments. We can also assume that privacy-conscious users will attempt to evade this monitoring -- for example, by ensuring that low-level identifiers such as link-layer addresses are "randomized", so that the devices do not broadcast the same unique identifier in every location that they visit.
有报道称，加拿大机场（CNBC）的无线连接监控系统将用于监控乘客的无线连接。我们可以假设这些都是一个更广泛系统的片段或试运行，该系统将尝试在互联网用户通过无线接入点和其他临时网络附件漫游时监控他们。我们还可以假设，关注隐私的用户会试图逃避这种监控——例如，通过确保诸如链路层地址之类的低级标识符是“随机的”，这样设备就不会在他们访问的每个位置广播相同的唯一标识符。
Of course, link-layer MAC (Media Access Control) addresses are not the only way to identify a device. As soon as it connects to a remote network, the device may use DHCP and DHCPv6 to obtain network parameters. The analysis of DHCP and DHCPv6 options shows that parameters of these protocols can reveal identifiers of the device, negating the benefits of link-layer address randomization. This is documented in detail in [RFC7819] and [RFC7824]. The natural reaction is to restrict the number and values of such parameters in order to minimize disclosure.
当然，链路层MAC（媒体访问控制）地址不是识别设备的唯一方法。一旦连接到远程网络，设备就可以使用DHCP和DHCPv6获取网络参数。对DHCP和DHCPv6选项的分析表明，这些协议的参数可以显示设备的标识符，从而否定了链路层地址随机化的好处。这在[RFC7819]和[RFC7824]中有详细记录。自然反应是限制此类参数的数量和值，以尽量减少披露。
In the absence of a common standard, different system developers are likely to implement this minimization of disclosure in different ways. Monitoring entities could then use the differences to identify the software version running on the device. The proposed anonymity profiles provide a common standard that minimizes information disclosure, including the disclosure of implementation identifiers.
在缺乏共同标准的情况下，不同的系统开发人员可能会以不同的方式实现这种披露最小化。然后，监控实体可以使用这些差异来识别设备上运行的软件版本。提议的匿名性配置文件提供了一个通用标准，可最大限度地减少信息披露，包括实施标识符的披露。
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 [RFC2119].
本文件中的关键词“必须”、“不得”、“必需”、“应”、“不应”、“应”、“不应”、“建议”、“可”和“可选”应按照[RFC2119]中所述进行解释。
Mobile nodes can be tracked using multiple identifiers, the most prominent being link-layer addresses, a.k.a. MAC addresses. For example, when devices use Wi-Fi connectivity, they place the MAC address in the header of all the packets that they transmit. Standard implementations of Wi-Fi use unique 48-bit link-layer addresses, assigned to the devices according to procedures defined by IEEE 802. Even when the Wi-Fi packets are encrypted, the portion of the header containing the addresses will be sent in cleartext. Tracking devices can "listen to the airwaves" to find out what devices are transmitting near them.
可以使用多个标识符跟踪移动节点，其中最突出的是链路层地址，即MAC地址。例如，当设备使用Wi-Fi连接时，它们会将MAC地址放在它们传输的所有数据包的报头中。Wi-Fi的标准实现使用唯一的48位链路层地址，根据IEEE 802定义的程序分配给设备。即使对Wi-Fi数据包进行加密，包含地址的报头部分也将以明文形式发送。跟踪设备可以“收听电波”，以了解在其附近传输的设备。
We can easily imagine that the MAC addresses can be correlated with other data, e.g., cleartext names and cookies, to build a registry linking MAC addresses to the identity of devices' owners. Once that correlation is done, tracking the MAC address is sufficient to track individual people, even when all application data sent from the devices is encrypted. Link-layer addresses can also be correlated with IP addresses of devices, negating the potential privacy benefits of IPv6 "privacy" addresses. Privacy advocates have reasons to be concerned.
我们可以很容易地想象，MAC地址可以与其他数据关联，例如明文名称和cookie，以建立一个注册表，将MAC地址与设备所有者的身份联系起来。一旦关联完成，跟踪MAC地址就足以跟踪个人，即使从设备发送的所有应用程序数据都已加密。链路层地址还可以与设备的IP地址相关联，从而否定IPv6“隐私”地址的潜在隐私优势。隐私权倡导者有理由担心。
The obvious solution is to "randomize" the MAC address. Before connecting to a particular network, the device replaces the MAC address with a randomly drawn 48-bit value. Link-layer address randomization was successfully tried at the IETF meeting in Honolulu in November 2014 [IETFMACRandom] and in subsequent meetings [IETFTrialsAndMore]; it is studied in the IEEE 802 EC Privacy Recommendation Study Group [IEEE802PRSG]. However, we have to consider the linkage between link-layer addresses, DHCP identifiers, and IP addresses.
显而易见的解决方案是“随机”MAC地址。在连接到特定网络之前，设备将用随机抽取的48位值替换MAC地址。2014年11月在檀香山举行的IETF会议[IETFMACRandom]和随后的会议[IETFTrialsAndMore]上成功尝试了链路层地址随机化；IEEE 802 EC隐私建议研究组[IEEE802PRSG]对此进行了研究。然而，我们必须考虑链路层地址、DHCP标识符和IP地址之间的链接。
There is not yet an established standard for randomizing link-layer addresses. Various prototypes have tried different strategies, such as:
目前还没有一个确定的随机链路层地址的标准。不同的原型尝试了不同的策略，例如：
Per connection: Configure a random link-layer address at the time of connecting to a network, e.g., to a specific Wi-Fi SSID (Service Set Identifier), and keep it for the duration of the connection.
每个连接：在连接到网络时配置随机链路层地址，例如连接到特定的Wi-Fi SSID（服务集标识符），并在连接期间保留该地址。
Per network: Same as "per connection", but always use the same link-layer address for the same network -- different, of course, from the addresses used in other networks.
每个网络：与“每个连接”相同，但始终为同一网络使用相同的链路层地址——当然，与其他网络中使用的地址不同。
Time interval: Change the link-layer address at regular time intervals.
时间间隔：以固定的时间间隔更改链路层地址。
In practice, there are many reasons to keep the link-layer address constant for the duration of a link-layer connection, as in the "per connection" or "per network" variants. In Wi-Fi networks, changing the link-layer address requires dropping the existing Wi-Fi connection and then re-establishing it, which implies repeating the connection process and associated procedures. The IP addresses will change, which means that all required TCP connections will have to be re-established. If the network access is provided through a NAT, changing IP addresses also means that the NAT traversal procedures will have to be restarted. This means a lot of disruption. At the same time, an observer on the network will easily notice that a
实际上，在链路层连接期间保持链路层地址不变有很多原因，如“每个连接”或“每个网络”变体。在Wi-Fi网络中，更改链路层地址需要断开现有Wi-Fi连接，然后重新建立连接，这意味着重复连接过程和相关过程。IP地址将发生变化，这意味着必须重新建立所有必需的TCP连接。如果通过NAT提供网络访问，更改IP地址也意味着必须重新启动NAT遍历过程。这意味着大量的破坏。同时，网络上的观察者很容易注意到
station left, another came in just after that, and the new one appears to be communicating with the same set of IP addresses as the old one. This provides for easy correlation.
站离开后，紧接着又进来了一个，新的站似乎与旧站使用相同的IP地址进行通信。这提供了容易的关联。
The anonymity profiles pretty much assume that the link-layer address randomization follows the "per connection" or "per network" strategies, or a variant of the "time interval" strategy in which the interval has about the same duration as the average connection.
匿名配置文件几乎假设链路层地址随机化遵循“每个连接”或“每个网络”策略，或“时间间隔”策略的变体，其中间隔的持续时间与平均连接的持续时间大致相同。
From a privacy point of view, it is clear that the link-layer address, IP address, and DHCP identifier shall evolve in synchrony. For example, if the link-layer address changes and the DHCP identifier stays constant, then it is really easy to correlate old and new link-layer addresses, either by listening to DHCP traffic or by observing that the IP address remains constant, since it is tied to the DHCP identifier. Conversely, if the DHCP identifier changes but the link-layer address remains constant, the old and new identifiers and addresses can be correlated by listening to L2 traffic. The procedures documented in the following sections construct DHCP identifiers from the current link-layer address, automatically providing for this synchronization.
从隐私的角度来看，很明显，链路层地址、IP地址和DHCP标识符应该同步发展。例如，如果链路层地址发生变化且DHCP标识符保持不变，则很容易通过侦听DHCP通信量或观察IP地址保持不变来关联新旧链路层地址，因为它与DHCP标识符相关联。相反，如果DHCP标识符改变，但链路层地址保持不变，则可以通过侦听L2通信来关联新旧标识符和地址。以下各节中记录的过程从当前链路层地址构造DHCP标识符，自动提供此同步。
The proposed anonymity profiles solve this synchronization issue by deriving most identifiers from the link-layer address and by generally making sure that DHCP parameter values do not remain constant after an address change.
建议的匿名性配置文件通过从链路层地址派生大多数标识符，并通过通常确保DHCP参数值在地址更改后不会保持不变，来解决此同步问题。
MAC address randomization solves the trivial monitoring problem in which someone just uses a Wi-Fi scanner and records the MAC addresses seen on the air. DHCP anonymity solves the more elaborate scenario in which someone monitors link-layer addresses and identities used in DHCP at the access point or DHCP server. But these are not the only ways to track a mobile device.
MAC地址随机化解决了一个琐碎的监控问题，即某人只需使用Wi-Fi扫描仪并记录在广播中看到的MAC地址。DHCP匿名性解决了更复杂的情况，即有人在访问点或DHCP服务器上监视DHCP中使用的链路层地址和身份。但这些并不是跟踪移动设备的唯一方法。
Radio fingerprinting is a process that identifies a radio transmitter by the unique "fingerprint" of its signal transmission, i.e., the tiny differences caused by minute imperfections of the radio transmission hardware. This can be applied to diverse types of radios, including Wi-Fi as described, for example, in [WiFiRadioFingerprinting]. No amount of link-layer address randomization will protect against such techniques. Protections may exist, but they are outside the scope of the present document.
无线电指纹识别是一种通过其信号传输的唯一“指纹”（即无线电传输硬件的微小缺陷引起的微小差异）来识别无线电发射机的过程。这可以应用于各种类型的无线电，包括Wi-Fi，如[WiFiRadioFingerprinting]中所述。再多的链路层地址随机化也不能防止这种技术。保护措施可能存在，但不在本文件的范围之内。
On the other hand, we should not renounce randomization just because radio fingerprinting exists. The radio fingerprinting techniques are harder to deploy than just recording link-layer addresses with a scanner. Such techniques can only track devices for which the fingerprints are known and thus have a narrower scope of application than mass monitoring of addresses and DHCP parameters.
另一方面，我们不应该仅仅因为存在无线电指纹就放弃随机化。无线电指纹识别技术比仅仅用扫描仪记录链路层地址更难部署。这种技术只能跟踪已知指纹的设备，因此比大规模监控地址和DHCP参数的应用范围更窄。
When a standard like DHCP allows for multiple options, different implementers will make different choices for the options that they support or the values they choose for the options. Conversely, monitoring the options and values present in DHCP messages reveals these differences and allows for "operating system fingerprinting", i.e., finding the type and version of software that a particular device is running. Finding these versions provides some information about the device's identity and thus goes against the goal of anonymity.
当DHCP这样的标准允许多个选项时，不同的实现者将对其支持的选项或为选项选择的值做出不同的选择。相反，监视DHCP消息中的选项和值会揭示这些差异，并允许“操作系统指纹”，即查找特定设备正在运行的软件的类型和版本。查找这些版本提供了有关设备身份的一些信息，因此不符合匿名性的目标。
The design of the anonymity profiles attempts to minimize the number of options and the choice of values, in order to reduce the possibilities of operating system fingerprinting.
匿名配置文件的设计试图最小化选项的数量和值的选择，以减少操作系统指纹识别的可能性。
Reviewers of the anonymity profiles have sometimes suggested adding an option to explicitly identify the profiles as "using the anonymity option". One suggestion is that the client tell the server about its desire to remain anonymous, so that a willing server could cooperate and protect the client's privacy. Another possibility would be to use a specific privacy-oriented construct, such as, for example, a new type of DHCP Unique Identifier (DUID) for a temporary DUID that would be changing over time.
匿名配置文件的审阅者有时建议添加一个选项，将配置文件明确标识为“使用匿名选项”。一个建议是，客户机告诉服务器其保持匿名的愿望，以便有意愿的服务器可以合作并保护客户机的隐私。另一种可能是使用特定的面向隐私的构造，例如，一种新类型的DHCP唯一标识符（DUID），用于将随时间变化的临时DUID。
This is not workable in a large number of cases, as it is possible that the network operator (or other entities that have access to the operator's network) might be actively participating in surveillance and anti-privacy, willingly or not. Declaring a preference for anonymity is a bit like walking around with a Guy Fawkes mask. (See [GuyFawkesMask] for an explanation of this usage.) When anonymity is required, it is generally not a good idea to stick out of the crowd. Simply revealing the desire for privacy could cause the attacker to react by triggering additional surveillance or monitoring mechanisms. Therefore, we feel that it is preferable to not disclose one's desire for privacy.
这在很多情况下都是不可行的，因为网络运营商（或有权访问运营商网络的其他实体）可能会主动参与监视和反隐私，不管是否愿意。宣称喜欢匿名有点像戴着盖伊·福克斯面具四处走动。（有关此用法的解释，请参见[GuyFawkesMask]）当需要匿名时，通常不适合站在人群之外。仅仅透露对隐私的渴望可能会导致攻击者通过触发额外的监视或监视机制做出反应。因此，我们认为最好不要透露个人对隐私的渴望。
This preference leads to some important implications. In particular, we make an effort to make the mitigation techniques difficult to distinguish from regular client behaviors, if at all possible.
这种偏好导致了一些重要的影响。特别是，如果可能的话，我们努力使缓解技术难以与常规客户行为区分开来。
There are downsides to randomizing link-layer addresses and DHCP identifiers. By definition, randomization will break management procedures that rely on tracking link-layer addresses. Even if this is not too much of a concern, we have to be worried about the frequency of link-layer address randomization. Suppose, for example, that many devices would get new random link-layer addresses at short intervals, maybe every few minutes. This would generate new DHCP requests in rapid succession, with a high risk of exhausting DHCPv4 address pools. Even with IPv6, there would still be a risk of increased neighbor discovery traffic and bloating of various address tables. Implementers will have to be cautious when programming devices to use randomized MAC addresses. They will have to carefully choose the frequency with which such addresses will be renewed.
将链路层地址和DHCP标识符随机化有缺点。根据定义，随机化将打破依赖于跟踪链路层地址的管理程序。即使这不是一个太大的问题，我们也必须担心链路层地址随机化的频率。例如，假设许多设备以很短的间隔（可能每隔几分钟）获得新的随机链路层地址。这将快速连续生成新的DHCP请求，很有可能耗尽DHCPv4地址池。即使使用IPv6，仍然存在邻居发现流量增加和各种地址表膨胀的风险。当编程设备使用随机MAC地址时，实现者必须谨慎。他们必须仔细选择更新这些地址的频率。
This document only provides guidelines for using DHCP when clients care about privacy. We assume that the request for anonymity is materialized by the assignment of a randomized link-layer address to the network interface. Once that decision is made, the following guidelines will avoid leakage of identity in DHCP parameters or in assigned addresses.
本文档仅提供在客户端关心隐私时使用DHCP的指南。我们假设匿名请求通过向网络接口分配随机链路层地址来实现。一旦做出决定，以下准则将避免DHCP参数或分配地址中的身份泄漏。
There may be rare situations where the clients want to remain anonymous to attackers but not to the DHCP server. These clients should still use link-layer address randomization to hide from observers, as well as some form of encrypted communication to the DHCP server. This scenario is out of scope for this document.
在很少的情况下，客户端希望对攻击者保持匿名，而不是对DHCP服务器保持匿名。这些客户端仍然应该使用链路层地址随机化来隐藏观察者，以及某种形式的到DHCP服务器的加密通信。此场景超出了本文档的范围。
To preserve anonymity, the clients need to not use stable values for the client identifiers. This is clearly a trade-off, because a stable client identifier guarantees that the client will receive consistent parameters over time. An example is given in [RFC7618], where the client identifier is used to guarantee that the same client will always get the same combination of IP address and port range. Static clients benefit most from stable parameters and often can already be identified by physical-connection-layer parameters. These static clients will normally not use the anonymity profiles. Mobile clients, in contrast, have the option of using the anonymity profiles in conjunction with [RFC7618] if they are more concerned with privacy protection than with stable parameters.
为了保持匿名性，客户端不需要为客户端标识符使用稳定的值。这显然是一种权衡，因为稳定的客户机标识符保证客户机将随时间接收到一致的参数。[RFC7618]中给出了一个示例，其中客户端标识符用于确保同一客户端始终获得相同的IP地址和端口范围组合。静态客户端从稳定的参数中获益最多，并且通常已经可以通过物理连接层参数来识别。这些静态客户端通常不会使用匿名配置文件。相反，如果移动客户端更关心隐私保护而不是稳定参数，则可以选择将匿名配置文件与[RFC7618]结合使用。
This document only provides recommendations for DHCP clients. The main targets are DHCP clients used in mobile devices. Such devices are tempting targets for various monitoring systems, so there is an urgent need to provide them with a simple anonymity solution. We can argue that some mobile devices embed DHCP servers and that providing solutions for such devices is also quite important. Two plausible examples would be a DHCP server for a car network and a DHCP server for a mobile hot spot. However, mobile servers get a lot of privacy protection through the use of access control and link-layer encryption. Servers may disclose information to clients through DHCP, but they normally only do that to clients that have passed the link-layer access control and have been authorized to use the network services. This arguably makes solving the server problem less urgent than solving the client problem.
本文档仅为DHCP客户端提供建议。主要目标是移动设备中使用的DHCP客户端。这些设备是各种监控系统的诱人目标，因此迫切需要为它们提供一个简单的匿名解决方案。我们可以说，一些移动设备嵌入了DHCP服务器，为这些设备提供解决方案也非常重要。两个可能的例子是用于汽车网络的DHCP服务器和用于移动热点的DHCP服务器。然而，通过使用访问控制和链路层加密，移动服务器获得了很多隐私保护。服务器可以通过DHCP向客户机披露信息，但通常仅向通过链路层访问控制并获得使用网络服务授权的客户机披露信息。这可以说使解决服务器问题比解决客户机问题更不紧迫。
Server privacy issues are presented in [RFC7819] and [RFC7824]. Mitigation of these issues is left for further study.
[RFC7819]和[RFC7824]中介绍了服务器隐私问题。这些问题的缓解有待进一步研究。
Clients using the DHCPv4 anonymity profile limit the disclosure of information by controlling the header parameters and by limiting the number and values of options. The number of options depends on the specific DHCP message:
使用DHCPv4匿名配置文件的客户端通过控制标头参数和限制选项的数量和值来限制信息的披露。选项的数量取决于特定的DHCP消息：
DHCPDISCOVER: The anonymized DHCPDISCOVER messages MUST contain the Message Type option, MAY contain the Client Identifier option, and MAY contain the Parameter Request List option. It SHOULD NOT contain any other option.
DHCPDISCOVER：匿名化的DHCPDISCOVER消息必须包含消息类型选项，可以包含客户端标识符选项，也可以包含参数请求列表选项。它不应包含任何其他选项。
DHCPREQUEST: The anonymized DHCPREQUEST messages MUST contain the Message Type option, MAY contain the Client Identifier option, and MAY contain the Parameter Request List option. If the message is in response to a DHCPOFFER, it MUST contain the corresponding Server Identifier option and the Requested IP address option. If the message is not in response to a DHCPOFFER, it MAY contain a Requested IP address option as explained in Section 3.3. It SHOULD NOT contain any other option.
DHCPREQUEST：匿名化的DHCPREQUEST消息必须包含Message Type选项，可以包含Client Identifier选项，也可以包含Parameter Request List选项。如果消息响应DHCPOFFERE，则它必须包含相应的服务器标识符选项和请求的IP地址选项。如果消息不是对DHCPOFFER的响应，它可能包含一个请求的IP地址选项，如第3.3节所述。它不应包含任何其他选项。
DHCPDECLINE: The anonymized DHCPDECLINE messages MUST contain the Message Type option, the Server Identifier option, and the Requested IP address option; and MAY contain the Client Identifier option.
DHCPDecept：匿名化的DHCPDecept消息必须包含消息类型选项、服务器标识符选项和请求的IP地址选项；并且可能包含客户端标识符选项。
DHCPRELEASE: The anonymized DHCPRELEASE messages MUST contain the Message Type option and the Server Identifier option, and MAY contain the Client Identifier option.
DHCPRELEASE：匿名DHCPRELEASE消息必须包含Message Type选项和Server Identifier选项，并且可能包含Client Identifier选项。
DHCPINFORM: The anonymized DHCPINFORM messages MUST contain the Message Type option, MAY contain the Client Identifier option, and MAY contain the Parameter Request List option. It SHOULD NOT contain any other option.
DHCPINFORM：匿名DHCPINFORM消息必须包含消息类型选项，可能包含客户端标识符选项，也可能包含参数请求列表选项。它不应包含任何其他选项。
Header fields and option values SHOULD be set in accordance with the DHCP specification, but some header fields and option values SHOULD be constructed per the following guidelines.
标题字段和选项值应根据DHCP规范进行设置，但某些标题字段和选项值应按照以下准则构造。
The inclusion of the Host Name and Fully Qualified Domain Name (FQDN) options in DHCPDISCOVER, DHCPREQUEST, or DHCPINFORM messages is discussed in Sections 3.7 and 3.8.
第3.7节和第3.8节讨论了在DHCPDISCOVER、DHCPREQUEST或DHCPINFORM消息中包含主机名和完全限定域名（FQDN）选项的问题。
There are many choices for implementing DHCPv4 messages. Clients can choose to transmit a specific set of options, pick a particular encoding for these options, and transmit options in different orders. These choices can be used to fingerprint the client.
实现DHCPv4消息有很多选择。客户端可以选择传输一组特定的选项，为这些选项选择特定的编码，并以不同的顺序传输选项。这些选项可用于对客户端进行指纹识别。
The following sections provide guidance on the encoding of options and fields within the packets. However, this guidance alone may not be sufficient to prevent fingerprinting from revealing the device type, the vendor name, or the OS type and specific version. Fingerprinting may also reveal whether the client is using the anonymity profile.
以下各节提供了有关数据包内选项和字段编码的指导。但是，仅此指南可能不足以防止指纹识别显示设备类型、供应商名称或操作系统类型和特定版本。指纹识别还可以显示客户端是否使用匿名配置文件。
The client intending to protect its privacy SHOULD limit the subset of options sent in messages to the subset listed in the remaining subsections.
打算保护其隐私的客户端应将消息中发送的选项子集限制为剩余小节中列出的子集。
The client intending to protect its privacy SHOULD randomize the ordering of options before sending any DHCPv4 message. If this random ordering cannot be implemented, the client MAY order the options by option code number (lowest to highest).
打算保护其隐私的客户机应在发送任何DHCPv4消息之前随机化选项顺序。如果无法执行此随机排序，客户可以按选项代码编号（从低到高）排序选项。
Four octets in the header of the DHCP messages carry the "Client IP address" (ciaddr) as defined in [RFC2131]. In DHCP, this field is used by the clients to indicate the address that they used previously, so that as much as possible the server can allocate the same address to them.
DHCP消息头中的四个八位字节携带[RFC2131]中定义的“客户端IP地址”（ciaddr）。在DHCP中，客户端使用此字段来指示他们以前使用的地址，以便服务器尽可能多地为他们分配相同的地址。
There are very few privacy implications related to sending this address in the DHCP messages, except in the case of connecting to a different network than the last network connected to previously. If the DHCP client somehow repeated the address used in a previous network attachment, monitoring services might use the information to tie the two network locations. DHCP clients SHOULD ensure that the field is cleared when they know that the network attachment has changed, particularly if the link-layer address is reset by a device's administrator.
在DHCP消息中发送此地址很少涉及隐私问题，除非连接到与以前连接到的最后一个网络不同的网络。如果DHCP客户端以某种方式重复了以前网络连接中使用的地址，则监视服务可能会使用该信息来连接两个网络位置。DHCP客户端应确保在知道网络连接已更改时清除该字段，特别是当设备管理员重置了链路层地址时。
The clients using the anonymity profile MUST NOT include in the message a Client IP address that has been obtained with a different link-layer address.
使用匿名配置文件的客户端不得在消息中包含使用不同链路层地址获得的客户端IP地址。
The Requested IP address option is defined in [RFC2132] with code 50. It allows the client to request that a particular IP address be assigned. This option is mandatory in some protocol messages per [RFC2131] -- for example, when a client selects an address offered by a server. However, this option is not mandatory in the DHCPDISCOVER message. It is simply a convenience -- an attempt to regain the same IP address that was used in a previous connection. Doing so entails the risk of disclosing an IP address used by the client at a previous location or with a different link-layer address. This risk exists for all forms of IP addresses, public or private, as some private addresses may be used in a wide scope, e.g., when an Internet Service Provider is using NAT.
请求的IP地址选项在[RFC2132]中定义，代码为50。它允许客户端请求分配特定的IP地址。根据[RFC2131]，此选项在某些协议消息中是必需的——例如，当客户端选择服务器提供的地址时。但是，此选项在DHCPDISCOVER消息中不是必需的。这只是一种方便——尝试重新获得以前连接中使用的相同IP地址。这样做可能会泄露客户端在以前位置或使用不同链路层地址使用的IP地址。这种风险存在于所有形式的IP地址（公共或私有），因为某些私有地址可能被广泛使用，例如，当互联网服务提供商使用NAT时。
When using the anonymity profile, clients SHOULD NOT use the Requested IP address option in DHCPDISCOVER messages. They MUST use the option when mandated by DHCP -- for example, in DHCPREQUEST messages.
使用匿名配置文件时，客户端不应在DHCPDISCOVER消息中使用请求的IP地址选项。当DHCP授权时，它们必须使用该选项——例如，在DHCPREQUEST消息中。
There are scenarios in which a client connecting to a network remembers a previously allocated address, i.e., when it is in the INIT-REBOOT state. In that state, any client that is concerned with privacy SHOULD perform a complete four-way handshake, starting with a DHCPDISCOVER, to obtain a new address lease. If the client can ascertain that this is exactly the same network to which it was previously connected, and if the link-layer address did not change, the client MAY issue a DHCPREQUEST to try to reclaim the current address.
在某些情况下，连接到网络的客户端会记住以前分配的地址，即，当它处于INIT-REBOOT状态时。在这种状态下，任何关心隐私的客户端都应该执行完整的四方握手，从DHCPDISCOVER开始，以获得新的地址租约。如果客户端可以确定这与它以前连接到的网络完全相同，并且如果链路层地址没有更改，则客户端可以发出DHCPREQUEST以尝试回收当前地址。
Sixteen octets in the header of the DHCP messages carry the "Client hardware address" (chaddr) as defined in [RFC2131]. The presence of this address is necessary for the proper operation of the DHCP service.
DHCP消息头中的16个八位字节携带[RFC2131]中定义的“客户端硬件地址”（chaddr）。此地址的存在对于DHCP服务的正常运行是必要的。
Hardware addresses, called "link-layer addresses" in many RFCs, can be used to uniquely identify a device, especially if they follow the IEEE 802 recommendations. If the hardware address is reset to a new randomized value, the DHCP client SHOULD use the new randomized value in the DHCP messages.
硬件地址，在许多RFC中称为“链路层地址”，可用于唯一标识设备，尤其是在遵循IEEE 802建议的情况下。如果硬件地址重置为新的随机值，DHCP客户端应在DHCP消息中使用新的随机值。
The Client Identifier option is defined in [RFC2132] with option code 61. It is discussed in detail in [RFC4361]. The purpose of the Client Identifier option is to identify the client in a manner independent of the link-layer address. This is particularly useful if the DHCP server is expected to assign the same address to the client after a network attachment is swapped and the link-layer address changes. It is also useful when the same node issues requests through several interfaces and expects the DHCP server to provide consistent configuration data over multiple interfaces.
[RFC2132]中定义了客户机标识符选项，选项代码为61。[RFC4361]对此进行了详细讨论。客户端标识符选项的目的是以独立于链路层地址的方式标识客户端。如果希望DHCP服务器在交换网络连接和更改链路层地址后将相同的地址分配给客户端，则这一点特别有用。当同一节点通过多个接口发出请求，并期望DHCP服务器通过多个接口提供一致的配置数据时，它也很有用。
The considerations for hardware independence and strong client identity have an adverse effect on the privacy of mobile clients, because the hardware-independent unique identifier obviously enables very efficient tracking of the clients' movements. One option would be to not transmit this option at all, but this may affect interoperability and will definitely mark the client as requesting anonymity, exposing it to the risks mentioned in Section 2.5.
硬件独立性和强客户端身份的考虑对移动客户端的隐私有不利影响，因为与硬件独立的唯一标识符显然能够非常有效地跟踪客户端的移动。一种选择是根本不传输此选项，但这可能会影响互操作性，并且肯定会将客户端标记为请求匿名，从而使其面临第2.5节中提到的风险。
The recommendations in [RFC4361] are very strong, stating, for example, that "DHCPv4 clients MUST NOT use client identifiers based solely on layer two addresses that are hard-wired to the layer two device (e.g., the Ethernet MAC address)." These strong recommendations are in fact a trade-off between ease of management and privacy, and the trade-off should depend on the circumstances.
[RFC4361]中的建议非常强烈，例如，指出“DHCPv4客户端不得仅基于硬连接到第二层设备的第二层地址（例如以太网MAC地址）使用客户端标识符。”这些强烈建议实际上是易于管理和隐私之间的折衷，而取舍应该取决于具体情况。
In contradiction to [RFC4361], when using the anonymity profile, DHCP clients MUST use client identifiers based solely on the link-layer address that will be used in the underlying connection. This will ensure that the DHCP client identifier does not leak any information that is not already available to entities monitoring the network connection. It will also ensure that a strategy of randomizing the link-layer address will not be nullified by the Client Identifier option.
与[RFC4361]相反，当使用匿名配置文件时，DHCP客户端必须仅基于将在基础连接中使用的链路层地址使用客户端标识符。这将确保DHCP客户端标识符不会泄漏监控网络连接的实体尚未获得的任何信息。它还将确保随机化链路层地址的策略不会被客户端标识符选项取消。
There are usages of DHCP where the underlying connection is a point-to-point link, in which case there is no link-layer address available to construct a non-revealing identifier. If anonymity is desired in such networks, the client SHOULD pick a random identifier that is highly likely to be unique to the current link, using, for example, a combination of a local secret and an identifier of the connection. The algorithm for combining secrets and identifiers, as described in Section 5 of [RFC7217], solves a similar problem. The criteria for the generation of random numbers are stated in [RFC4086].
DHCP的一些用法是，底层连接是点对点链接，在这种情况下，没有链接层地址可用于构造非公开标识符。如果在此类网络中需要匿名性，则客户端应使用例如本地秘密和连接的标识符的组合来选择很可能是当前链路唯一的随机标识符。[RFC7217]第5节所述的组合机密和标识符的算法解决了类似的问题。[RFC4086]中规定了生成随机数的标准。
The Parameter Request List (PRL) option is defined in [RFC2132] with option code 55. It lists the parameters requested from the server by the client. Different implementations request different parameters. [RFC2132] specifies that "the client MAY list the options in order of preference." In practice, this means that different client implementations will request different parameters, in different orders.
[RFC2132]中定义了参数请求列表（PRL）选项，选项代码为55。它列出了客户端从服务器请求的参数。不同的实现要求不同的参数。[RFC2132]指定“客户机可以按优先顺序列出选项”。实际上，这意味着不同的客户机实现将以不同的顺序请求不同的参数。
The choice of option numbers and the specific ordering of option numbers in the PRL can be used to fingerprint the client. This may not reveal the identity of a client but may provide additional information such as the device type, the vendor name, or the OS type and specific version.
PRL中选项编号的选择和选项编号的特定顺序可用于对客户进行指纹识别。这可能不会显示客户端的身份，但可能会提供附加信息，如设备类型、供应商名称或操作系统类型和特定版本。
The client intending to protect its privacy SHOULD only request a minimal number of options in the PRL and SHOULD also randomly shuffle the ordering of option codes in the PRL. If this random ordering cannot be implemented, the client MAY order the option codes in the PRL by option code number (lowest to highest).
打算保护其隐私的客户应仅请求PRL中最少数量的选项，还应随机调整PRL中选项代码的顺序。如果无法执行此随机排序，客户可以按选项代码编号（从低到高）在PRL中排序选项代码。
The Host Name option is defined in [RFC2132] with option code 12. Depending on implementations, the option value can carry either an FQDN such as "node1984.example.com" or a simple host name such as "node1984". The host name is commonly used by the DHCP server to identify the host and also to automatically update the address of the host in local name services.
主机名选项在[RFC2132]中定义，选项代码为12。根据实现情况，选项值可以携带FQDN（如“node1984.example.com”）或简单主机名（如“node1984”）。DHCP服务器通常使用主机名来标识主机，并在本地名称服务中自动更新主机地址。
FQDNs are obviously unique identifiers, but even simple host names can provide a significant amount of information on the identity of the device. They are typically chosen to be unique in the context where the device is most often used. In a context that contains a substantial number of devices, e.g., in a large company or a big university, the host name will be a pretty good identifier of the
FQDN显然是唯一的标识符，但即使是简单的主机名也可以提供有关设备标识的大量信息。它们通常被选择为在设备最常使用的环境中是唯一的。在包含大量设备的上下文中，例如在一家大公司或一所大大学中，主机名将是设备的一个非常好的标识符
device, due to the specificity required to ensure uniqueness. Monitoring services could use that information in conjunction with traffic analysis and quickly derive the identity of the device's owner.
设备，由于所需的特殊性，以确保唯一性。监控服务可以将该信息与流量分析结合使用，并快速获得设备所有者的身份。
When using the anonymity profile, DHCP clients SHOULD NOT send the Host Name option. If they choose to send the option, DHCP clients MUST always send a non-qualified host name instead of an FQDN and MUST obfuscate the host name value.
使用匿名配置文件时，DHCP客户端不应发送主机名选项。如果选择发送选项，DHCP客户端必须始终发送非限定主机名而不是FQDN，并且必须混淆主机名值。
There are many ways to obfuscate a host name. The construction rules SHOULD guarantee that a different host name is generated each time the link-layer address changes and that the obfuscated host name will not reveal the underlying link-layer address. The construction SHOULD generate names that are unique enough to minimize collisions in the local link. Clients MAY use the following algorithm: compute a secure hash of a local secret and of the link-layer address that will be used in the underlying connection, and then use the hexadecimal representation of the first 6 octets of the hash as the obfuscated host name.
有许多方法可以混淆主机名。构造规则应保证每次链接层地址更改时都会生成不同的主机名，并且经过模糊处理的主机名不会显示底层链接层地址。构造应生成足够唯一的名称，以最小化本地链接中的冲突。客户端可以使用以下算法：计算本地机密和将在基础连接中使用的链路层地址的安全哈希，然后使用哈希的前6个八位字节的十六进制表示形式作为模糊主机名。
The algorithm described in the previous paragraph generates an easily recognizable pattern. There is a potential downside to having such a specific name pattern for hosts that require anonymity (the "sticking out of the crowd" principle), as explained in Section 2.5. For this reason, the above algorithm is just a suggestion.
上一段中描述的算法生成一个易于识别的模式。如第2.5节所述，对于需要匿名的主机，使用这种特定的名称模式有一个潜在的缺点（“突出人群”原则）。因此，上述算法只是一个建议。
The Client FQDN option is defined in [RFC4702] with option code 81. This option allows the DHCP clients to advertise to the DHCP server their FQDN, such as "mobile.example.com". This would allow the DHCP server to update in the DNS the PTR record for the IP address allocated to the client. Depending on circumstances, either the DHCP client or the DHCP server could update in the DNS the A record for the FQDN of the client.
[RFC4702]中定义了客户机FQDN选项，选项代码为81。此选项允许DHCP客户端向DHCP服务器播发其FQDN，如“mobile.example.com”。这将允许DHCP服务器在DNS中更新分配给客户端的IP地址的PTR记录。根据具体情况，DHCP客户端或DHCP服务器都可以在DNS中更新客户端FQDN的A记录。
Obviously, this option uniquely identifies the client, exposing it to the DHCP server or to anyone listening to DHCP traffic. In fact, if the DNS record is updated, the location of the client becomes visible to anyone with DNS lookup capabilities.
显然，此选项唯一地标识客户机，将其暴露给DHCP服务器或任何侦听DHCP通信的人。事实上，如果更新了DNS记录，则具有DNS查找功能的任何人都可以看到客户端的位置。
When using the anonymity profile, DHCP clients SHOULD NOT include the Client FQDN option in their DHCP requests. Alternatively, they MAY include a special-purpose FQDN using the same host name as in the Host Name option, with a suffix matching the connection-specific DNS suffix being advertised by that DHCP server. Having a name in the
使用匿名配置文件时，DHCP客户端不应在其DHCP请求中包含客户端FQDN选项。或者，它们可能包括使用与主机名选项中相同主机名的专用FQDN，其后缀与该DHCP服务器播发的连接特定DNS后缀匹配。在报纸上有名字
DNS allows working with legacy systems that require one to be there, e.g., by verifying that a forward and reverse lookup succeeds with the same result.
DNS允许使用需要存在的遗留系统，例如，通过验证正向和反向查找是否成功并获得相同的结果。
The UUID/GUID-based (where "UUID" means "Universally Unique Identifier" and "GUID" means "Globally Unique Identifier") Client Machine Identifier option is defined in [RFC4578] with option code 97. This option is part of a set of options for the Intel Preboot eXecution Environment (PXE). The purpose of the PXE system is to perform management functions on a device before its main OS is operational. The Client Machine Identifier carries a 16-octet GUID that uniquely identifies the device.
基于UUID/GUID（其中“UUID”表示“通用唯一标识符”，“GUID”表示“全局唯一标识符”）的客户机标识符选项在[RFC4578]中定义，选项代码为97。此选项是“英特尔预引导执行环境”（PXE）的一组选项的一部分。PXE系统的目的是在设备的主操作系统运行之前在设备上执行管理功能。客户端计算机标识符包含一个16位字节的GUID，用于唯一标识设备。
The PXE system is clearly designed for devices operating in a controlled environment. The main usage of the PXE system is to install a new version of the operating system through a high-speed Ethernet connection. The process is typically controlled from the user interface during the boot process. Common sense seems to dictate that getting a new operating system from an unauthenticated server at an untrusted location is a really bad idea and that even if the option was available users would not activate it. In any case, the option is only used in the "pre-boot" environment, and there is no reason to use it once the system is up and running. Nodes visiting untrusted networks MUST NOT send or use the PXE options.
PXE系统显然是为在受控环境中运行的设备而设计的。PXE系统的主要用途是通过高速以太网连接安装新版本的操作系统。该过程通常在引导过程中通过用户界面进行控制。常识似乎表明，在不受信任的位置从未经验证的服务器获取新的操作系统是一个非常糟糕的主意，即使该选项可用，用户也不会激活它。在任何情况下，该选项仅在“预引导”环境中使用，一旦系统启动并运行，就没有理由使用它。访问不受信任网络的节点不得发送或使用PXE选项。
Vendor-identifying options are defined in [RFC2132] and [RFC3925]. When using the anonymity profile, DHCPv4 clients SHOULD NOT use the Vendor-Specific Information option (code 43), the Vendor Class Identifier option (code 60), the V-I Vendor Class option (code 124), or the V-I Vendor-Specific Information option (code 125), as these options potentially reveal identifying information.
供应商识别选项在[RFC2132]和[RFC3925]中定义。使用匿名配置文件时，DHCPv4客户端不应使用供应商特定信息选项（代码43）、供应商类别标识符选项（代码60）、V-I供应商类别选项（代码124）或V-I供应商特定信息选项（代码125），因为这些选项可能会显示识别信息。
DHCPv6 is typically used by clients in one of two scenarios: stateful or stateless configuration. In the stateful scenario, clients use a combination of Solicit, Request, Confirm, Renew, Rebind, Release, and Decline messages to obtain addresses and manage these addresses.
DHCPv6通常由客户机在以下两种场景之一中使用：有状态或无状态配置。在有状态场景中，客户端使用请求、请求、确认、续订、重新绑定、释放和拒绝消息的组合来获取地址并管理这些地址。
In the stateless scenario, clients configure addresses using a combination of client-managed identifiers and router-advertised prefixes, without involving the DHCPv6 services. Different ways of constructing these prefixes have different implications on privacy, which are discussed in [DEFAULT-IIDs] and [RFC7721]. In the stateless scenario, clients use DHCPv6 to obtain network configuration parameters, through the Information-request message.
在无状态场景中，客户端使用客户端管理的标识符和路由器播发的前缀组合来配置地址，而不涉及DHCPv6服务。构造这些前缀的不同方法对隐私有不同的影响，这在[DEFAULT IID]和[RFC7721]中进行了讨论。在无状态场景中，客户端使用DHCPv6通过信息请求消息获取网络配置参数。
The choice between the stateful and stateless scenarios depends on flag and prefix options published by the Router Advertisement messages of local routers, as specified in [RFC4861]. When these options enable stateless address configuration, hosts using the anonymity profile SHOULD use stateless address configuration instead of stateful address configuration, because stateless configuration requires fewer information disclosures than stateful configuration.
有状态和无状态场景之间的选择取决于本地路由器的路由器广告消息发布的标志和前缀选项，如[RFC4861]中所述。当这些选项启用无状态地址配置时，使用匿名配置文件的主机应该使用无状态地址配置，而不是有状态地址配置，因为无状态配置比有状态配置需要更少的信息披露。
When using the anonymity profile, DHCPv6 clients carefully select DHCPv6 options used in the various messages that they send. The list of options that are mandatory or optional for each message is specified in [RFC3315]. Some of these options have specific implications on anonymity. The following sections provide guidance on the choice of option values when using the anonymity profile.
在使用匿名配置文件时，DHCPv6客户端会仔细选择它们发送的各种消息中使用的DHCPv6选项。[RFC3315]中规定了每条消息的强制或可选选项列表。其中一些选项对匿名性有特定的影响。以下各节提供了使用匿名配置文件时选择选项值的指导。
There are many choices for implementing DHCPv6 messages. As explained in Section 3.1, these choices can be used to fingerprint the client.
实现DHCPv6消息有很多选择。如第3.1节所述，这些选项可用于对客户进行指纹识别。
The following sections provide guidance on the encoding of options. However, this guidance alone may not be sufficient to prevent fingerprinting from revealing the device type, the vendor name, or the OS type and specific version. Fingerprinting may also reveal whether the client is using the anonymity profile.
以下各节提供了有关选项编码的指导。但是，仅此指南可能不足以防止指纹识别显示设备类型、供应商名称或操作系统类型和特定版本。指纹识别还可以显示客户端是否使用匿名配置文件。
The client intending to protect its privacy SHOULD limit the subset of options sent in messages to the subset listed in the following sections.
打算保护其隐私的客户端应将消息中发送的选项子集限制为以下部分中列出的子集。
The client intending to protect its privacy SHOULD randomize the ordering of options before sending any DHCPv6 message. If this random ordering cannot be implemented, the client MAY order the options by option code number (lowest to highest).
打算保护其隐私的客户端应在发送任何DHCPv6消息之前随机化选项顺序。如果无法执行此随机排序，客户可以按选项代码编号（从低到高）排序选项。
4.2. Do not send Confirm messages, unless really sure about the location
4.2. 除非确实确定位置，否则不要发送确认消息
[RFC3315] requires clients to send a Confirm message when they attach to a new link to verify whether the addressing and configuration information they previously received is still valid. This requirement was relaxed in [DHCPv6bis]. When these clients send Confirm messages, they include any Identity Associations (IAs) assigned to the interface that may have moved to a new link, along with the addresses associated with those IAs. By examining the addresses in the Confirm message, an attacker can trivially identify the previous point(s) of attachment.
[RFC3315]要求客户端在连接到新链接时发送确认消息，以验证之前收到的地址和配置信息是否仍然有效。[DHCPv6bis]放宽了这一要求。当这些客户端发送确认消息时，它们包括分配给可能已移动到新链接的接口的任何标识关联（IAs），以及与这些IAs关联的地址。通过检查确认消息中的地址，攻击者可以轻松识别以前的附件点。
Clients interested in protecting their privacy SHOULD NOT send Confirm messages and instead SHOULD directly try to acquire addresses on the new link. However, not sending Confirm messages can result in connectivity hiatus in some scenarios, e.g., roaming between two access points in the same wireless network. DHCPv6 clients that can verify that the previous link and the current link are part of the same network MAY send Confirm messages while still protecting their privacy. Such link identification should happen before DHCPv6 is used, and thus it cannot depend on the DHCPv6 information used in [RFC6059]. In practice, the most reliable detection of network attachment is through link-layer security, e.g., [IEEE8021X].
对保护隐私感兴趣的客户不应发送确认消息，而应直接尝试获取新链接上的地址。但是，在某些情况下，不发送确认消息可能会导致连接中断，例如，在同一无线网络中的两个接入点之间漫游。DHCPv6客户端可以验证上一个链路和当前链路是否属于同一网络，可以发送确认消息，同时仍然保护其隐私。这种链路识别应该在使用DHCPv6之前进行，因此它不能依赖于[RFC6059]中使用的DHCPv6信息。实际上，最可靠的网络连接检测是通过链路层安全性，例如[IEEE8021X]。
The DHCPv6 Client Identifier option is defined in [RFC3315] with option code 1. The purpose of the Client Identifier option is to identify the client to the server. The content of the option is a DHCP Unique Identifier (DUID). One of the primary privacy concerns is that a client is disclosing a stable identifier (the DUID) that can be used for tracking and profiling. Three DUID formats are specified in [RFC3315]: link-layer address plus time (DUID-LLT), Vendor-assigned unique ID based on Enterprise Number, and link-layer address. A fourth type, DUID-UUID, is defined in [RFC6355].
[RFC3315]中定义了DHCPv6客户机标识符选项，选项代码为1。客户端标识符选项的目的是向服务器标识客户端。该选项的内容是DHCP唯一标识符（DUID）。一个主要的隐私问题是，客户机正在公开一个可用于跟踪和分析的稳定标识符（DUID）。[RFC3315]中规定了三种DUID格式：链路层地址加时间（DUID-LLT）、基于企业编号的供应商分配的唯一ID和链路层地址。第四种类型DUID-UUID在[RFC6355]中定义。
When using the anonymity profile in conjunction with randomized link-layer addresses, DHCPv6 clients MUST use DUID format number 3 -- link-layer address. The value of the link-layer address should be the value currently assigned to the interface.
当将匿名配置文件与随机链路层地址结合使用时，DHCPv6客户端必须使用DUID格式编号3——链路层地址。链路层地址的值应为当前分配给接口的值。
When using the anonymity profile without the benefit of randomized link-layer addresses, clients that want to protect their privacy SHOULD generate a new randomized DUID-LLT every time they attach to a new link or detect a possible link change event. Syntactically, this identifier will conform to [RFC3315], but its content is meaningless. The exact details are left up to implementers, but there are several
当使用匿名配置文件而不使用随机链路层地址时，希望保护其隐私的客户端应在每次连接到新链路或检测到可能的链路更改事件时生成新的随机DUID-LLT。在语法上，该标识符将符合[RFC3315]，但其内容没有意义。具体细节由实现者决定，但有几个方面
factors that should be taken into consideration. The DUID type SHOULD be set to 1 (DUID-LLT). Hardware type SHOULD be set appropriately to the hardware type in question. The link address embedded in the LLT SHOULD be set to a randomized value. Time SHOULD be set to a random timestamp from the previous year. Time MAY be set to current time, but this will reveal the fact that the DUID is newly generated and thus could provide information for device fingerprinting. The criteria for generating highly unique random numbers are listed in [RFC4086].
应考虑的因素。DUID类型应设置为1（DUID-LLT）。硬件类型应适当设置为相关硬件类型。嵌入在LLT中的链接地址应设置为随机值。时间应设置为上一年的随机时间戳。时间可以设置为当前时间，但这将揭示DUID是新生成的，因此可以为设备指纹识别提供信息。[RFC4086]中列出了生成高度唯一随机数的标准。
According to [RFC3315], a DHCPv6 client includes its client identifier in most of the messages it sends. There is one exception, however: the client is allowed to omit its client identifier when sending Information-request messages.
根据[RFC3315]，DHCPv6客户机在其发送的大多数消息中都包含其客户机标识符。但是，有一个例外：在发送信息请求消息时，允许客户机省略其客户机标识符。
When using stateless DHCPv6, clients wanting to protect their privacy SHOULD NOT include client identifiers in their Information-request messages. This will prevent the server from specifying client-specific options if it is configured to do so, but the need for anonymity precludes such options anyway.
使用无状态DHCPv6时，希望保护其隐私的客户端不应在其信息请求消息中包含客户端标识符。如果服务器被配置为指定特定于客户端的选项，这将阻止服务器指定特定于客户端的选项，但是匿名性的需要排除了这些选项。
When using the anonymity profile, DHCPv6 clients SHOULD use the Server Identifier option (code 2) as specified in [RFC3315]. Clients MUST only include server identifier values that were received with the current link-layer address, because the reuse of old values discloses information that can be used to identify the client.
使用匿名配置文件时，DHCPv6客户端应使用[RFC3315]中指定的服务器标识符选项（代码2）。客户机必须仅包括使用当前链路层地址接收的服务器标识符值，因为重用旧值会泄露可用于标识客户机的信息。
When using the anonymity profile, DHCPv6 clients might have to use Solicit or Request messages to obtain IPv6 addresses through the DHCPv6 server. In DHCPv6, the collection of addresses assigned to a client is identified by an IA. Clients interested in privacy SHOULD request addresses using the IA for the Non-temporary Addresses option (IA_NA, code 3) [RFC3315].
使用匿名配置文件时，DHCPv6客户端可能必须使用请求或请求消息通过DHCPv6服务器获取IPv6地址。在DHCPv6中，分配给客户机的地址集合由IA标识。对隐私感兴趣的客户应使用IA请求非临时地址选项的地址（IA_NA，代码3）[RFC3315]。
The IA_NA option includes an IAID parameter that identifies a unique IA for the interface for which the address is requested. Clients interested in protecting their privacy MUST ensure that the IAID does not enable client identification. They also need to conform to the requirement of [RFC3315] that the IAID for that IA MUST be consistent across restarts of the DHCPv6 client. We interpret that as requiring that the IAID MUST be constant for the association, as long as the link-layer address remains constant.
IA_NA选项包括一个IAID参数，该参数标识请求地址的接口的唯一IA。有兴趣保护其隐私的客户必须确保IAID不会启用客户标识。它们还需要符合[RFC3315]的要求，即该IA的IAID必须在DHCPv6客户端的重启期间保持一致。我们认为，只要链路层地址保持不变，就要求关联的IAID必须保持不变。
Clients MAY meet the privacy, uniqueness, and stability requirements of the IAID by constructing it as the combination of 1 octet encoding the interface number in the system, and the first 3 octets of the link-layer address.
客户端可以通过将IAID构造为系统中编码接口号的1个八位字节和链路层地址的前3个八位字节的组合来满足IAID的隐私性、唯一性和稳定性要求。
The clients MAY use the IA Address option (code 5) [RFC3315] but need to balance the potential advantage of "address continuity" versus the potential risk of "previous address disclosure". A potential solution is to remove all stored addresses when a link-layer address changes and to only use the IA Address option with addresses that have been explicitly assigned through the current link-layer address.
客户可以使用IA地址选项（代码5）[RFC3315]，但需要平衡“地址连续性”的潜在优势与“先前地址泄露”的潜在风险。一种可能的解决方案是，当链路层地址发生更改时，删除所有存储的地址，并仅对通过当前链路层地址显式分配的地址使用IA地址选项。
[RFC3315] defines a special container (IA_TA, code 4) for requesting temporary addresses. This is a good mechanism in principle, but there are a number of issues associated with it. First, this is not a widely used feature, so clients depending solely on temporary addresses may lock themselves out of service. Secondly, [RFC3315] does not specify any lifetime or lease length for temporary addresses. Therefore, support for renewing temporary addresses may vary between client implementations, including no support at all. Finally, by requesting temporary addresses, a client reveals its desire for privacy and potentially risks countermeasures as described in Section 2.5.
[RFC3315]定义用于请求临时地址的特殊容器（IA_TA，代码4）。原则上，这是一个很好的机制，但也存在一些相关问题。首先，这不是一个广泛使用的特性，因此仅依赖临时地址的客户端可能会将自己锁定在服务之外。其次，[RFC3315]没有为临时地址指定任何生存期或租约长度。因此，对更新临时地址的支持可能因客户端实现而异，包括根本不支持。最后，如第2.5节所述，通过请求临时地址，客户揭示了其对隐私的渴望和潜在风险对策。
Because of these issues, clients interested in their privacy SHOULD NOT use IA_TA.
由于这些问题，对其隐私感兴趣的客户不应使用IA_TA。
The addresses obtained according to Section 4.5 are meant to be non-temporary, but the anonymity profile uses them as temporary, and they will be discarded when the link-layer address is changed. They thus meet most of the use cases of the temporary addresses defined in [RFC4941]. Clients interested in their privacy should not publish their IPv6 addresses in the DNS or otherwise associate them with name services, and thus do not normally need two classes of addresses -- one public, one temporary.
根据第4.5节获得的地址是非临时的，但匿名配置文件将其用作临时地址，当链路层地址更改时，这些地址将被丢弃。因此，它们满足[RFC4941]中定义的临时地址的大多数用例。对其隐私感兴趣的客户端不应在DNS中发布其IPv6地址，或以其他方式将其与名称服务关联，因此通常不需要两类地址——一类是公共地址，一类是临时地址。
The use of mechanisms to allocate several IPv6 addresses to a client while preserving privacy is left for further study.
在保护隐私的同时，使用机制将多个IPv6地址分配给客户端还有待进一步研究。
The use of DHCPv6 address assignment option for Prefix Delegation (PD) is defined in [RFC3633]. Because current host OS implementations do not typically request prefixes, clients that wish to use DHCPv6 PD -- just like clients that wish to use any DHCP or DHCPv6 option that is not currently widely used -- should recognize that doing so will serve as a form of fingerprinting, unless or until the use of DHCPv6 PD by clients becomes more widespread.
[RFC3633]中定义了前缀委派（PD）使用DHCPv6地址分配选项。由于当前的主机操作系统实现通常不请求前缀，因此希望使用DHCPv6 PD的客户端（就像希望使用当前未广泛使用的任何DHCP或DHCPv6选项的客户端一样）应该认识到这样做将作为一种指纹形式，除非或直到客户机使用DHCPv6 PD变得更广泛。
The anonymity properties of DHCPv6 PD, which uses IA_PD IAs, are similar to those of DHCPv6 address assignment using IA_NA IAs. The IAID could potentially be used to identify the client, and a prefix hint sent in the IA_PD Prefix option could be used to track the client's previous location. Clients that desire anonymity and never request more than one prefix SHOULD set the IAID value to zero, as authorized in Section 6 of [RFC3633], and SHOULD NOT document any previously assigned prefix in the IA_PD Prefix option.
使用IA_PD IAs的DHCPv6 PD的匿名性属性与使用IA_NA IAs的DHCPv6地址分配的匿名性属性类似。IAID可能用于标识客户机，而IA_PD prefix选项中发送的前缀提示可用于跟踪客户机以前的位置。如[RFC3633]第6节所授权，要求匿名且从不请求多个前缀的客户端应将IAID值设置为零，并且不应在IA_PD prefix选项中记录任何先前分配的前缀。
The Option Request Option (ORO) is defined in [RFC3315] with option code 6. It specifies the options that the client is requesting from the server. The choice of requested options and the order of encoding of these options in the ORO can be used to fingerprint the client.
[RFC3315]中定义了选项请求选项（ORO），选项代码为6。它指定客户端从服务器请求的选项。所请求选项的选择以及这些选项在ORO中的编码顺序可用于对客户端进行指纹识别。
The client intending to protect its privacy SHOULD only request a minimal subset of options and SHOULD randomly shuffle the ordering of option codes in the ORO. If this random ordering cannot be implemented, the client MAY order the option codes in the ORO by option code number (lowest to highest).
有意保护其隐私的客户应仅请求最小的选项子集，并应随机调整ORO中选项代码的顺序。如果无法执行此随机排序，客户可以按选项代码编号（从低到高）在ORO中排序选项代码。
According to [RFC3315], the client that includes an ORO in a Solicit or Request message MAY additionally include instances of those options that are identified in the ORO, with data values as hints to the server about parameter values the client would like to have returned.
根据[RFC3315]，在请求或请求消息中包括ORO的客户端还可以包括在ORO中标识的那些选项的实例，其中数据值作为关于客户端希望返回的参数值的提示发送给服务器。
When using the anonymity profile, clients SHOULD NOT include such instances of options, because old values might be used to identify the client.
在使用匿名配置文件时，客户端不应包含此类选项实例，因为旧值可能用于标识客户端。
The purpose of the Authentication option (code 11) [RFC3315] is to authenticate the identity of clients and servers and the contents of DHCPv6 messages. As such, the option can be used to identify the client, so it is incompatible with the stated goal of "client anonymity". DHCPv6 clients that use the anonymity profile SHOULD NOT use the Authentication option. They MAY use it if they recognize that they are operating in a trusted environment, e.g., in a workplace network.
验证选项（代码11）[RFC3315]的目的是验证客户端和服务器的身份以及DHCPv6消息的内容。因此，该选项可用于识别客户，因此不符合“客户匿名”的既定目标。使用匿名配置文件的DHCPv6客户端不应使用身份验证选项。如果他们认识到自己是在一个可信的环境中工作，例如在工作场所网络中，他们可能会使用它。
When using the anonymity profile, DHCPv6 clients SHOULD NOT use the User Class option (code 15) or the Vendor Class option (code 16) [RFC3315], as these options potentially reveal identifying information.
当使用匿名配置文件时，DHCPv6客户端不应使用用户类选项（代码15）或供应商类选项（代码16）[RFC3315]，因为这些选项可能会显示识别信息。
The DHCPv6 Client FQDN option is defined in [RFC4704] with option code 39. This option allows the DHCPv6 clients to advertise to the DHCPv6 server their FQDN, such as "mobile.example.com". When using the anonymity profile, DHCPv6 clients SHOULD NOT include the Client FQDN option in their DHCPv6 messages, because it identifies the client. As explained in Section 3.8, they MAY use a local-only FQDN by combining a host name derived from the link-layer address and a suffix advertised by the local DHCPv6 server.
[RFC4704]中定义了DHCPv6客户端FQDN选项，选项代码为39。此选项允许DHCPv6客户端向DHCPv6服务器播发其FQDN，例如“mobile.example.com”。使用匿名配置文件时，DHCPv6客户端不应在其DHCPv6消息中包含客户端FQDN选项，因为它标识客户端。如第3.8节所述，他们可以通过组合从链路层地址派生的主机名和本地DHCPv6服务器公布的后缀来使用仅本地FQDN。
The anonymity profiles have the effect of hiding the client identity from the DHCP server. This is not always desirable. Some DHCP servers provide facilities like publishing names and addresses in the DNS, or ensuring that returning clients get reassigned the same address.
匿名配置文件的作用是对DHCP服务器隐藏客户端身份。这并不总是可取的。一些DHCP服务器提供了一些功能，如在DNS中发布名称和地址，或确保返回的客户端重新分配相同的地址。
Clients using an anonymity profile may be consuming more resources. For example, when a client changes its link-layer address and requests a new IP address, the old IP address is still marked as leased by the server.
使用匿名配置文件的客户端可能会消耗更多资源。例如，当客户机更改其链路层地址并请求新的IP地址时，旧的IP地址仍被服务器标记为已租用。
Some DHCP servers will only give addresses to pre-registered MAC addresses, forcing clients to choose between remaining anonymous and obtaining connectivity.
一些DHCP服务器将只向预先注册的MAC地址提供地址，迫使客户端在保持匿名和获得连接之间进行选择。
Implementers SHOULD provide a way for clients to control when the anonymity profiles are used and when standard behavior is preferred.
实现者应该为客户端提供一种方法来控制何时使用匿名配置文件以及何时首选标准行为。
Implementers MAY implement this control by tying the use of the anonymity profiles to that of link-layer address randomization.
实现者可以通过将匿名配置文件的使用与链路层地址随机化的使用捆绑起来来实现该控制。
The use of the anonymity profiles does not change the security considerations of the DHCPv4 or DHCPv6 protocols [RFC2131] [RFC3315].
匿名配置文件的使用不会改变DHCPv4或DHCPv6协议[RFC2131][RFC3315]的安全注意事项。
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, <http://www.rfc-editor.org/info/rfc2119>.
[RFC2119]Bradner，S.，“RFC中用于表示需求水平的关键词”，BCP 14，RFC 2119，DOI 10.17487/RFC2119，1997年3月<http://www.rfc-editor.org/info/rfc2119>.
[RFC2131] Droms, R., "Dynamic Host Configuration Protocol", RFC 2131, DOI 10.17487/RFC2131, March 1997, <http://www.rfc-editor.org/info/rfc2131>.
[RFC2131]Droms，R.，“动态主机配置协议”，RFC 2131，DOI 10.17487/RFC2131，1997年3月<http://www.rfc-editor.org/info/rfc2131>.
[RFC3315] Droms, R., Ed., Bound, J., Volz, B., Lemon, T., Perkins, C., and M. Carney, "Dynamic Host Configuration Protocol for IPv6 (DHCPv6)", RFC 3315, DOI 10.17487/RFC3315, July 2003, <http://www.rfc-editor.org/info/rfc3315>.
[RFC3315]Droms，R.，Ed.，Bound，J.，Volz，B.，Lemon，T.，Perkins，C.，和M.Carney，“IPv6的动态主机配置协议（DHCPv6）”，RFC 3315，DOI 10.17487/RFC3315，2003年7月<http://www.rfc-editor.org/info/rfc3315>.
[RFC3633] Troan, O. and R. Droms, "IPv6 Prefix Options for Dynamic Host Configuration Protocol (DHCP) version 6", RFC 3633, DOI 10.17487/RFC3633, December 2003, <http://www.rfc-editor.org/info/rfc3633>.
[RFC3633]Troan，O.和R.Droms，“动态主机配置协议（DHCP）版本6的IPv6前缀选项”，RFC 3633，DOI 10.17487/RFC3633，2003年12月<http://www.rfc-editor.org/info/rfc3633>.
[RFC4702] Stapp, M., Volz, B., and Y. Rekhter, "The Dynamic Host Configuration Protocol (DHCP) Client Fully Qualified Domain Name (FQDN) Option", RFC 4702, DOI 10.17487/RFC4702, October 2006, <http://www.rfc-editor.org/info/rfc4702>.
[RFC4702]Stapp，M.，Volz，B.，和Y.Rekhter，“动态主机配置协议（DHCP）客户端完全限定域名（FQDN）选项”，RFC 4702，DOI 10.17487/RFC4702，2006年10月<http://www.rfc-editor.org/info/rfc4702>.
[RFC4861] Narten, T., Nordmark, E., Simpson, W., and H. Soliman, "Neighbor Discovery for IP version 6 (IPv6)", RFC 4861, DOI 10.17487/RFC4861, September 2007, <http://www.rfc-editor.org/info/rfc4861>.
[RFC4861]Narten，T.，Nordmark，E.，Simpson，W.，和H.Soliman，“IP版本6（IPv6）的邻居发现”，RFC 4861，DOI 10.17487/RFC48612007年9月<http://www.rfc-editor.org/info/rfc4861>.
[RFC4941] Narten, T., Draves, R., and S. Krishnan, "Privacy Extensions for Stateless Address Autoconfiguration in IPv6", RFC 4941, DOI 10.17487/RFC4941, September 2007, <http://www.rfc-editor.org/info/rfc4941>.
[RFC4941]Narten，T.，Draves，R.，和S.Krishnan，“IPv6中无状态地址自动配置的隐私扩展”，RFC 4941，DOI 10.17487/RFC49411907年9月<http://www.rfc-editor.org/info/rfc4941>.
[CNBC] Weston, G., Greenwald, G., and R. Gallagher, "CBC News: CSEC used airport Wi-Fi to track Canadian travellers: Edward Snowden documents", January 2014, <http://www.cbc.ca/news/politics/ csec-used-airport-wi-fi-to-track-canadian-travellers-edward-snowden-documents-1.2517881>.
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[DEFAULT-IIDs] Gont, F., Cooper, A., Thaler, D., and W. Liu, "Recommendation on Stable IPv6 Interface Identifiers", Work in Progress, draft-ietf-6man-default-iids-11, April 2016.
[默认IIDs]Gont，F.，Cooper，A.，Thaler，D.，和W.Liu，“关于稳定IPv6接口标识符的建议”，正在进行的工作，草稿-ietf-6man-DEFAULT-IIDs-112016年4月。
[DHCPv6bis] Mrugalski, T., Ed., Siodelski, M., Volz, B., Yourtchenko, A., Richardson, M., Jiang, S., and T. Lemon, "Dynamic Host Configuration Protocol for IPv6 (DHCPv6) bis", Work in Progress, draft-ietf-dhc-rfc3315bis-04, March 2016.
[DHCPv6bis]Mrugalski，T.，Ed.，Siodelski，M.，Volz，B.，Yourtchenko，A.，Richardson，M.，Jiang，S.，和T.Lemon，“IPv6（DHCPv6）bis的动态主机配置协议”，正在进行中的工作，草案-ietf-dhc-rfc3315bis-04，2016年3月。
[GuyFawkesMask] Nickelsburg, M., "A brief history of the Guy Fawkes mask", July 2013, <http://theweek.com/articles/463151/ brief-history-guy-fawkes-mask>.
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[IEEE8021X]IEEE，“局域网和城域网的IEEE标准-基于端口的网络访问控制”，IEEE 802.1X-2010，DOI 10.1109/ieeestd.2010.5409813<http://ieeexplore.ieee.org/servlet/ opac？punumber=5409757>。
[IEEE802PRSG] IEEE 802 EC PRSG, "IEEE 802 EC Privacy Recommendation Study Group", February 2016, <http://www.ieee802.org/PrivRecsg/>.
[IEEE802PRSG]IEEE 802 EC PRSG，“IEEE 802 EC隐私建议研究小组”，2016年2月<http://www.ieee802.org/PrivRecsg/>.
[IETFMACRandom] Zuniga, JC., "MAC Privacy", November 2014, <http://www.ietf.org/blog/2014/11/mac-privacy/>.
[IETFMACRandom]祖尼加，JC.，“MAC隐私”，2014年11月<http://www.ietf.org/blog/2014/11/mac-privacy/>.
[IETFTrialsAndMore] Bernardos, CJ., Zuniga, JC., and P. O'Hanlon, "Wi-Fi Internet connectivity and privacy: hiding your tracks on the wireless Internet", October 2015, <http://www.it.uc3m.es/cjbc/papers/ pdf/2015_bernardos_cscn_privacy.pdf>.
[IETFTrialsAndMore]Bernardos，CJ.，Zuniga，JC.，和P.O'Hanlon，“Wi-Fi互联网连接和隐私：在无线互联网上隐藏您的曲目”，2015年10月<http://www.it.uc3m.es/cjbc/papers/ pdf/2015\u bernardos\u cscn\u privacy.pdf>。
[RFC2132] Alexander, S. and R. Droms, "DHCP Options and BOOTP Vendor Extensions", RFC 2132, DOI 10.17487/RFC2132, March 1997, <http://www.rfc-editor.org/info/rfc2132>.
[RFC2132]Alexander，S.和R.Droms，“DHCP选项和BOOTP供应商扩展”，RFC 2132，DOI 10.17487/RFC2132，1997年3月<http://www.rfc-editor.org/info/rfc2132>.
[RFC3925] Littlefield, J., "Vendor-Identifying Vendor Options for Dynamic Host Configuration Protocol version 4 (DHCPv4)", RFC 3925, DOI 10.17487/RFC3925, October 2004, <http://www.rfc-editor.org/info/rfc3925>.
[RFC3925]Littlefield，J.，“动态主机配置协议版本4（DHCPv4）的供应商识别供应商选项”，RFC 3925，DOI 10.17487/RFC3925，2004年10月<http://www.rfc-editor.org/info/rfc3925>.
[RFC4086] Eastlake 3rd, D., Schiller, J., and S. Crocker, "Randomness Requirements for Security", BCP 106, RFC 4086, DOI 10.17487/RFC4086, June 2005, <http://www.rfc-editor.org/info/rfc4086>.
[RFC4086]Eastlake 3rd，D.，Schiller，J.，和S.Crocker，“安全的随机性要求”，BCP 106，RFC 4086，DOI 10.17487/RFC4086，2005年6月<http://www.rfc-editor.org/info/rfc4086>.
[RFC4361] Lemon, T. and B. Sommerfeld, "Node-specific Client Identifiers for Dynamic Host Configuration Protocol Version Four (DHCPv4)", RFC 4361, DOI 10.17487/RFC4361, February 2006, <http://www.rfc-editor.org/info/rfc4361>.
[RFC4361]Lemon，T.和B.Sommerfeld，“动态主机配置协议第四版（DHCPv4）的节点特定客户端标识符”，RFC 4361，DOI 10.17487/RFC4361，2006年2月<http://www.rfc-editor.org/info/rfc4361>.
[RFC4578] Johnston, M. and S. Venaas, Ed., "Dynamic Host Configuration Protocol (DHCP) Options for the Intel Preboot eXecution Environment (PXE)", RFC 4578, DOI 10.17487/RFC4578, November 2006, <http://www.rfc-editor.org/info/rfc4578>.
[RFC4578]Johnston，M.和S.Venaas，编辑，“英特尔预引导执行环境（PXE）的动态主机配置协议（DHCP）选项”，RFC 4578，DOI 10.17487/RFC4578，2006年11月<http://www.rfc-editor.org/info/rfc4578>.
[RFC4704] Volz, B., "The Dynamic Host Configuration Protocol for IPv6 (DHCPv6) Client Fully Qualified Domain Name (FQDN) Option", RFC 4704, DOI 10.17487/RFC4704, October 2006, <http://www.rfc-editor.org/info/rfc4704>.
[RFC4704]Volz，B.，“IPv6（DHCPv6）客户端完全限定域名（FQDN）选项的动态主机配置协议”，RFC 4704，DOI 10.17487/RFC4704，2006年10月<http://www.rfc-editor.org/info/rfc4704>.
[RFC6059] Krishnan, S. and G. Daley, "Simple Procedures for Detecting Network Attachment in IPv6", RFC 6059, DOI 10.17487/RFC6059, November 2010, <http://www.rfc-editor.org/info/rfc6059>.
[RFC6059]Krishnan，S.和G.Daley，“IPv6中检测网络连接的简单程序”，RFC 6059，DOI 10.17487/RFC6059，2010年11月<http://www.rfc-editor.org/info/rfc6059>.
[RFC6355] Narten, T. and J. Johnson, "Definition of the UUID-Based DHCPv6 Unique Identifier (DUID-UUID)", RFC 6355, DOI 10.17487/RFC6355, August 2011, <http://www.rfc-editor.org/info/rfc6355>.
[RFC6355]Narten，T.和J.Johnson，“基于UUID的DHCPv6唯一标识符（DUID-UUID）的定义”，RFC 6355，DOI 10.17487/RFC6355，2011年8月<http://www.rfc-editor.org/info/rfc6355>.
[RFC7217] Gont, F., "A Method for Generating Semantically Opaque Interface Identifiers with IPv6 Stateless Address Autoconfiguration (SLAAC)", RFC 7217, DOI 10.17487/RFC7217, April 2014, <http://www.rfc-editor.org/info/rfc7217>.
[RFC7217]Gont，F.“使用IPv6无状态地址自动配置（SLAAC）生成语义不透明接口标识符的方法”，RFC 7217，DOI 10.17487/RFC72172014年4月<http://www.rfc-editor.org/info/rfc7217>.
[RFC7618] Cui, Y., Sun, Q., Farrer, I., Lee, Y., Sun, Q., and M. Boucadair, "Dynamic Allocation of Shared IPv4 Addresses", RFC 7618, DOI 10.17487/RFC7618, August 2015, <http://www.rfc-editor.org/info/rfc7618>.
[RFC7618]Cui，Y.，Sun，Q.，Farrer，I.，Lee，Y.，Sun，Q.，和M.Boucadair，“共享IPv4地址的动态分配”，RFC 7618，DOI 10.17487/RFC7618，2015年8月<http://www.rfc-editor.org/info/rfc7618>.
[RFC7721] Cooper, A., Gont, F., and D. Thaler, "Security and Privacy Considerations for IPv6 Address Generation Mechanisms", RFC 7721, DOI 10.17487/RFC7721, March 2016, <http://www.rfc-editor.org/info/rfc7721>.
[RFC7721]Cooper，A.，Gont，F.，和D.Thaler，“IPv6地址生成机制的安全和隐私考虑”，RFC 7721，DOI 10.17487/RFC7721，2016年3月<http://www.rfc-editor.org/info/rfc7721>.
[RFC7819] Jiang, S., Krishnan, S., and T. Mrugalski, "Privacy Considerations for DHCP", RFC 7819, DOI 10.17487/RFC7819, April 2016, <http://www.rfc-editor.org/info/rfc7819>.
[RFC7819]Jiang，S.，Krishnan，S.，和T.Mrugalski，“DHCP的隐私考虑”，RFC 7819，DOI 10.17487/RFC78192016年4月<http://www.rfc-editor.org/info/rfc7819>.
[RFC7824] Krishnan, S., Mrugalski, T., and S. Jiang, "Privacy Considerations for DHCPv6", RFC 7824, DOI 10.17487/RFC7824, May 2016, <http://www.rfc-editor.org/info/rfc7824>.
[RFC7824]Krishnan，S.，Mrugalski，T.，和S.Jiang，“DHCPv6的隐私考虑”，RFC 7824DOI 10.17487/RFC78242016年5月<http://www.rfc-editor.org/info/rfc7824>.
[WiFiRadioFingerprinting] Brik, V., Banerjee, S., Gruteser, M., and S. Oh, "Wireless Device Identification with Radiometric Signatures", DOI 10.1.1.145.8873, September 2008, <http://citeseerx.ist.psu.edu/viewdoc/ summary?doi=10.1.1.145.8873>.
[WiFiRadioFingerprinting]Brik，V.，Banerjee，S.，Gruteser，M.，和S.Oh，“具有辐射特征的无线设备识别”，DOI 10.1.1.145.88732008年9月<http://citeseerx.ist.psu.edu/viewdoc/ 总结？doi=10.1.1.145.8873>。
Acknowledgments
致谢
The inspiration for this document came from discussions in the Perpass mailing list. Several people provided feedback on this document, notably Noel Anderson, Brian Carpenter, Lorenzo Colitti, Stephen Farrell, Nick Grifka, Tushar Gupta, Brian Haberman, Gabriel Montenegro, Marcin Siodelski, Dave Thaler, Bernie Volz, and Jun Wu.
本文件的灵感来自Perpass邮件列表中的讨论。一些人对此文件提供了反馈，尤其是Noel Anderson、Brian Carpenter、Lorenzo Coletti、Stephen Farrell、Nick Grifka、Tushar Gupta、Brian Haberman、Gabriel黑山、Marcin Siodelski、Dave Thaler、Bernie Volz和Jun Wu。
Authors' Addresses
作者地址
Christian Huitema Microsoft Redmond, WA 98052 United States
Christian Huitema微软雷德蒙德，华盛顿州，美国，98052
Email: huitema@microsoft.com
Email: huitema@microsoft.com
Tomek Mrugalski Internet Systems Consortium, Inc. 950 Charter Street Redwood City, CA 94063 United States
美国加利福尼亚州红木市Charter Street 950号Tomek Mrugalski Internet Systems Consortium，Inc.94063
Email: tomasz.mrugalski@gmail.com
Email: tomasz.mrugalski@gmail.com
Suresh Krishnan Ericsson 8400 Decarie Blvd. Town of Mount Royal, QC Canada
苏雷什·克里希南·爱立信德卡里大道8400号。加拿大皇家山镇
Phone: +1 514 345 7900 x42871
Email: suresh.krishnan@ericsson.com
Phone: +1 514 345 7900 x42871
Email: suresh.krishnan@ericsson.com