Internet DRAFT - draft-wang-secure-access-of-iot-terminals
draft-wang-secure-access-of-iot-terminals
Internet Engineering Task Force B. Wang, Ed.
Internet-Draft S. Liu, Ed.
Intended status: Standards Track L. Wan, Ed.
Expires: 21 April 2024 Hikvision
J. Li, Ed.
CICS-CERT
X. Wang, Ed.
H.N. Yan, Ed.
Y.H. Xie, Ed.
Hikvision
19 October 2023
Technical Requirements for Secure Access and Management of IoT Smart
Terminals
draft-wang-secure-access-of-iot-terminals-05
Abstract
It is difficult to supervise the great deal of Internet of Things
(IoT) smart terminals which are widely distributed. Furthermore, a
large number of smart terminals (such as IP cameras, access control
terminals, traffic cameras, etc.) running on the network have high
security risks in access control. This draft introduces the
technical requirements for access management and control of IoT smart
terminals, which is used to solve the problem of personate and
illegal connection in the access process, and enables users to
strengthen the control of devices and discover devices that is
offline in time, so as to ensure the safety and stability of smart
terminals in the access process.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
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Task Force (IETF). Note that other groups may also distribute
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material or to cite them other than as "work in progress."
This Internet-Draft will expire on 21 April 2024.
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Copyright Notice
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. The Network Structure of IoT System . . . . . . . . . . . . . 3
3. Security Threats and Challenges . . . . . . . . . . . . . . . 6
4. Current Technology Level . . . . . . . . . . . . . . . . . . 6
5. Secure Access and Management of IoT Smart Terminals . . . . . 7
5.1. Framework of Secure Access Management . . . . . . . . . . 7
5.1.1. *Sensing & Controlling Domain* . . . . . . . . . . . 9
5.1.2. *Access & Management Domain* . . . . . . . . . . . . 9
5.1.3. *Application & Service Domain* . . . . . . . . . . . 10
5.1.4. *User Domain* . . . . . . . . . . . . . . . . . . . . 10
5.2. *Requirements for Device Security Access* . . . . . . . . 10
5.2.1. *Requirements for Devices Access Authentication
Identity Information* . . . . . . . . . . . . . . . . 10
5.2.2. *Requirements for Access Status of Devices* . . . . . 10
5.2.3. *Recommendation of Access Policy* . . . . . . . . . . 10
5.3. *Requirements for Management of Terminals* . . . . . . . 11
5.4. *Requirements for Device Protocol Access* . . . . . . . . 11
5.4.1. *Requirements for Access Log Audit* . . . . . . . . . 11
6. Security Considerations . . . . . . . . . . . . . . . . . . . 12
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 12
8. Informative References . . . . . . . . . . . . . . . . . . . 12
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 13
1. Introduction
With the rapid development of the IoT and the IP-based communication
system, a large number of terminals have been interconnected through
the network. Due to numerous branches of IoT network and the
scattered distribution of smart terminals, it is difficult for human
to supervise. Therefore, how to ensure the full-time control and
available of IoT network becomes a new problem. A large number of
smart terminals (such as IP cameras, access control terminals,
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traffic cameras and other dumb terminals), which running in the
network, have a large security risk in terms of security access
control. With the further development of the convergence of IoT
systems and information network, if IoT smart terminals are once used
by hackers, it is easy for hackers to penetrate the whole network
through IoT smart terminals, causing core business systems unable to
work and a large amount of confidential information to leak, which
will bring huge loss. Therefore, the establishment of a perfect
access control mechanism and application control mechanism of smart
terminals is an important part of the IoT security system.
This draft outlines the technical requirements for secure access and
management of smart terminals in the IoT to address the security
threats and challenges that exist in the access process of terminals.
We discuss the networking structure of common IoT smart terminals in
Section 2. Security threats and challenges faced in the access
process of IoT smart terminals in will be clarified in Section 3. In
Section 4, we review the guidelines and regulations related to the
access of IoT terminals. In Section 5, we present the requirements
for secure access and management of IoT smart terminals and describes
in detail. This draft provides a reference for IoT security access
and management .
2. The Network Structure of IoT System
Under normal circumstances, IoT smart terminals are connected to the
network through IoT gateway, and then the data of terminals is
reported to the application center through IoT gateway, which builds
the complete network.
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The diagram of an IoT system is shown in the figure below. In the
perception layer, four types of IoT smart terminals form four
subsystems, which are video monitoring subsystem, access control
subsystem, alarm subsystem and intercom subsystem. The smart
terminals in each subsystem are different. In the video monitoring
subsystem, the main terminals are IP cameras and intelligent cameras
for collecting video and image data. In the access control
subsystem, the main terminals are turnstiles and vehicle access
control hosts for collecting vehicle information. In the alarm
subsystem, the main terminals are alarm hosts, alarm keyboards and
wireless alarm hosts, which are used to set alarm policies, issue
alarm warnings and report alarm events, etc. In the intercom
subsystem, its main terminals are intercom hosts and individual
equipment, which are used to collect voice data. Through this
figure, we can know that in the IoT system, smart terminals are
heterogeneous and complex, and the data are aggregated into the
application layer through the transport layer, which greatly
increases the difficulty of the application layer to control the
terminals in the sensing layer.
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+----------------------------------------------------------------------+
| |
| Application +------------+ |
| Layer +--------+ | Video | |
| +--------+ | Storage| +-------+ | Integrated | |
| | HOST | | System | | DVI +-----+ Platform | |
| +---+----+ +---+----+ +---+---+ +------+-----+ |
| | | | | |
| | | | | |
+------------------+------------+--+----------+----------------+-------+
| | |
| | |
| Transport +-----+----+ |
| Layer | Router | |
| +-----+----+ |
| | |
| +------------------+-+------------+----------------+ |
| | | | | |
| +-+-------+ +----+----+ +----+----+ +-----+---+ |
| | Gateway | | Gateway | | Gateway | | Gateway | |
| +-+-------+ +----+----+ +----+----+ +-----+---+ |
| | | | | |
| | | | | |
+----------------------------------------------------------------------+
| | | | | |
+-------------+--+ +-------------+--+ +--------+-----+ +--------+-----+
| Video | | Access | | Alarm | | Intercom |
| Surveillance | | Control | | Subsystem | | Subsystem |
| Subsystem | | Subsystem | | +----------+ | | |
| +------------+ | | +------------+ | | |Alarm Host| | | +----------+ |
| | IP Camera | | | | Turnstile | | | +----------+ | | |Intercom | |
| +------------+ | | +------------+ | | | Alarm | | | | Host | |
| | Ip Camera | | | | Vehicle | | | | Keyboard | | | +----------+ |
| +------------+ | | | Access | | | +----------+ | | |Individual| |
| |Smart Camera| | | |Control Host| | | | Wireless | | | |Equipment | |
| +------------+ | | +------------+ | | |Alarm Host| | | | | |
+----------------+ +----------------+ | +----------+ | | +----------+ |
| +--------------+ +--------------+
| Perception |
| Layer |
| |
+----------------------------------------------------------------------+
Figure: The Network Structure of an IoT System
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3. Security Threats and Challenges
The main security threats and challenges in the process of accessing
IoT smart terminals are as follows:
1. Illegal connection: By IoT smart terminals, illegal devices and
hosts may access to the network for probing and attacking. The
application layer network may be invaded by smart terminals,
which will lead to information leakage.
2. Personate connection: Wide distribution of IoT smart terminals
and the public deployment environment make it easy for malicious
devices to impersonate legitimate devices and upload fake data,
which will lead to abnormal function of the devices and causes
great damage to the security of IoT.
3. Devices offline: IoT smart terminals are numerous and very
vulnerable when they suffer from physical attacks, network
anomalies, power supply anomalies, and aging of device, which
leads them to work offline. However, offline devices are
difficult to discover, causing the loss of some functions.
4. Devices management: There are many kinds of IoT smart terminals,
and it is often not clear how many IoT smart terminals are in the
whole IoT network and how many IoT smart terminals have security
problems, which leads to unable to control IoT smart terminals
and sort out device assets.
4. Current Technology Level
1. On the access control of IoT, many control protocols applied to
IoT smart terminals have been proposed, such as Zigbee [ZB], DALI
[DALI], BACNET [BACNET], which do not contribute to the secure
access of IoT devices. The UPnP [ISOIEC23941] access protocol
defines the access to IoT smart terminals, but does not consider
the issue of secure access.
2. There are many specialized and generic security protocols being
used in current IP-based deployments of IoT smart device
applications. For example, IPsec [RFC7296], TLS [RFC8446], DTLS
[RFC6347], HIP [RFC7401], Kerberos [RFC4120], SASL [RFC4422], and
EAP [RFC3748], etc. However, these protocols also can not
protect against illegal connection, personate connection and
offline encountered during device access.
3. There are also a number of groups that focus on IoT device
security. For example, the Cloud Security Alliance (CSA)
recommended that when enterprises build the IoT network, they
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should strengthen IoT smart device authentication/authorization
[CSA]. The Global System for Mobile communications Association
(GSMA) has published a security guide for IoT systems [GSMA] to
bring a set of security guidelines to the research of IoT
security product. The United States Department of Homeland
Security(DHS) has proposed six IoT security strategic principles
[DHS] to guide IoT developers, manufacturers, service providers,
and consumers in considering security issues. These teams give
good advice on building security for the IoT, but there is no
introduction or description of secure access to the IoT.
4. The current security standards on IoT, such as [RFC8576],
introduce the security issues and solutions, but there is no
mention of the problems and solutions in the access process of
smart terminals.
5. In other related device access standards, there are device access
and portal-based authentication based on 802.1x [ISO88021X].
However, due to IoT smart terminals are mainly dumb terminals,
they are not suitable for authentication access through 802.1x or
portal, and the two authentication methods cannot be used to
solve the illegal and personate connection of devices.
5. Secure Access and Management of IoT Smart Terminals
5.1. Framework of Secure Access Management
Comparing to three-layer framework of IoT,a layer of access and
management is added for the framework of secure access management,
which is between transport layer and application layer. The
framework of secure access management for IoT smart terminals is
shown in the following figure. In this framework, the access process
of IoT is divided into four parts, which are sensing&control domain,
access&management domain, application&service domain, and user
domain. Among them, access&management domain is the specific
implementation of the secure access and management technical
requirements to ensure secure access of smart terminals in terms of
smart terminals management, access control, strategy management and
access log audit.
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+-------------------------------------------------------User Domain----+
| Application & Service Domain |
| +------------------+ +------------------+ +-------------------+ |
| |Bussiness System 1| |Bussiness System 2| |Bussiness System...| |
| +------------------+ +------------------+ +-------------------+ |
+----------------------------------------------------------------------+
^ ^ ^
| | |
+----------+----------------+----------------+----------User Domain----+
| Access & Management Domain |
| +-----------------+-----------------+----------------+-------------+ |
| | Device | Device Access | Access Policy | Log Audit | |
| | Management | +-------------+ | Management | | |
| | | | Unique ID | | | | |
| | | | Information | | | | |
| | +-----+-------+ | +-------------+ | +------------+ | | |
| | | IP | Port& | | | Trusted | | | IP&MAC | | +---------+ | |
| | | |Service| | |Communication| | +------------+ | |Exception| | |
| | +-------------+ | | Protocol | | |IP&MAC&Brand| | +---------+ | |
| | |Type | Brand | | +-------------+ | +------------+ | |Behavior | | |
| | +-------------+ | | Certificate | | |IP&MAC&Brand| | +---------+ | |
| | |Model| MAC | | | access | | | &Model | | |Operation| | |
| | +-------------+ | +-------------+ | +------------+ | +---------+ | |
| +------------------------------------------------------------------+ |
+----------------------------------------------------------------------+
Indirect ^ ^ ^ Direct
Connection| | | Connection
+----------------------------------------------------------------------+
| Sensing & +-----------+ | | |
| Controlling |IoT Gateway| | | |
| Domain +------^----+ | | |
| | | | |
| +------------------------------------------------------------------+ |
| | +---------+ +---------+ +--------+ | +------+ | +------+ | |
| | |RS-485 | |Zigbee | |IP/WIFI/| | |Video | | |Smart | | |
| | |RS232 | |Lora and | |5G/4G | | |and | | |IP | | |
| | |and Other| |Other | |Smart +--+ |Audio +-+ |Camera| | |
| | |Wired | |Wireless | |Device | |Device| +------+ | |
| | |Terminals| |Terminals| +--------+ |RFID | | |
| | +---------+ +---------+ +------+ | |
| +------------------------------------------------------------------+ |
+----------------------------------------------------------------------+
Figure: Framework of Secure Access Management for Smart Terminals
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5.1.1. *Sensing & Controlling Domain*
Smart Terminals: Include wired terminals like RS-485, RS-232 and
other devices, wireless terminals such as ZigBee, LoRa and other
devices, smart devices like smart IP, WiFi, 5G, 4G, audio and video
device and RFID, etc.
IOT Gateway: An entity used to connect smart terminals and upper
layer, which is able to store data, compute data and transform
protocol.
Among them, smart terminals can be directly connected to the access
&-management domain, or indirectly connected to the access &
management domain through the IoT gateway.
5.1.2. *Access & Management Domain*
Access & management domain is the core, which is used to manage and
control the access of smart terminals, including four parts: device
management, device access, access policy management and log audit.
The contents of each part are clarified as follows:
Device Management: It mainly manages device asset information,
including status, IP address, MAC address, type, brand, model,
firmware version, open port and service of smart terminals.
Device Access: It refers to the device access mode supported by smart
terminals, including access based on unique identification
information of smart terminals (the composition of it can be one or
more sets of device asset information), access based on trusted
communication protocol of smart terminals and access based on
certificate authentication.
Access Policy Management: It refers to the access policy management
based on the unique identification information of smart terminals.
The access policy includes IP&MAC access policy, IP&MAC&brand access
policy, IP&MAC&brand&model access policy.
Log Audit: Used to record, store and audit the log information
generated in the access process of smart terminals, including
exception log audit, behavior log audit and operation log audit.
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5.1.3. *Application & Service Domain*
Application & service domain is the core business system, which
provides informational application services for information
collecting, exchanging and processing. The information provided by
the smart terminals is verified by the access & management domain to
ensure security and stability of the system.
5.1.4. *User Domain*
User domain refers to the users of smart terminals who can directly
access the core business system in application & service domain, and
view the access condition of smart terminals and manage them in
access & management domain.
5.2. *Requirements for Device Security Access*
5.2.1. *Requirements for Devices Access Authentication Identity
Information*
The identity information of devices should include one or more of the
following characteristics:
1.IP Address 2.MAC Address 3.Brand 4.Type 5.Model 6.Firmware Version
7.Port & Service
5.2.2. *Requirements for Access Status of Devices*
There should be at least four types of access status:
1.Online: The device that has been authenticated and is still working
well. 2.Offline: The device that has been authenticated whereas is
not connected to network. 3.Replacement: The device that has not been
authenticated whereas its authentication information is as the same
as other authenticated device. 4.Illegal connection: The device that
has not been authenticated and its information is different from
other authenticated device.
5.2.3. *Recommendation of Access Policy*
1.The device access policy should have at least five combinations:
a. IP + MAC
b. IP + MAC + Brand
c. IP + MAC + Brand + Model
d. IP + MAC + Brand + Model + Type
e. IP + MAC + Brand + Model + Type + Firmware Version 2.The illegal
access of replacement device and illegal connection device can be
quickly discovered and prevented. 3.The configuration of access
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policy can be done manually and automatically. 4.The access policy
can be customized by any combination of recommendation of access
policy shown in requirement 1.
5.3. *Requirements for Management of Terminals*
Device management requires to monitor status of terminals in real
time, to profile terminals, to identify and manage applications
running on terminals, to identify and manage asset information of
terminals, and to manage IP addresses of terminals.
1.Requirements for condition monitoring and management of terminals
a.It should be able to monitor the offline and online status of smart
terminals in real time. b.It should be able to discover whether
there is a weak password information of the smart terminal. c.It
should be able to discover the risky ports of smart terminals. d.It
should be able to alert offline devices or the devices with weak
passwords and risky ports. 2.Requirements for management of terminal
profiling a.It should be able to visualize the information of smart
terminals, including IP address, brand, type, model, etc.
3.Requirements for management of identifying applications a.It should
be able to automatically identify and manage the devices' open
services and service ports. b.It should be able to automatically
discover andidentify the application system of B/S architecture or C/
S architecture running in the network where the IoT smart terminal
located, including IP, service port, application name. 4.Requirements
for management of identifying asset information of the device a.It
should be able to manage IP address, MAC address, brand, model, type,
firmware version, open port, and online time of smart terminals.
b.It should be able to manage the communicationprotocol information.
c.It should be able to manage the geographiclocation information of
terminals
5.4. *Requirements for Device Protocol Access*
Device Protocol Access requires the ability to release trusted
protocol of IoT smart terminals and block untrusted protocols.
1.It should release IoT protocols, such as http, mqtt, onvif, coap,
etc. 2.It should block illegal protocols in real time, such as ssh,
ftp, telnet, etc. 3.It should select the corresponding protocols
based on the specific business scenario, such as rtsp, onvif, and
other protocols that used in the video surveillance field.
5.4.1. *Requirements for Access Log Audit*
Access log audit requires the ability to audit all types of
operations, such as abnormal and malicious behavior of access.
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1.It should record abnormal behavior log information of access in
real time and provide analysis and audit functions. 2.It should
record malicious behavior log information of access in real time and
provide analysis and audit functions. 3.It should record the
management, access and blocking of access devices and other types of
operations in real time, and provide analysis and audit functions.
6. Security Considerations
This entire memo deals with security issues.
7. IANA Considerations
This documents has no IANA actions.
8. Informative References
[BACNET] American Society of Heating, Refrigerating and Air-
Conditioning Engineers (ASHRAE), "BACnet",
<http://www.bacnet.org>.
[CSA] "Security Guidance for Early Adopters of the Internet of
Things (IoT)", 2015,
<https://downloads.cloudsecurityalliance.org/whitepapers/S
ecurity_Guidance_for_Early_Adopters_of_the_Internet_of_Thi
ngs.pdf>.
[DALI] "DALI Explained", <http://www.dalibydesign.us/dali.html>.
[DHS] "Strategic Principles For Securing the Internet of Things
(IoT)", 2016,
<https://www.dhs.gov/sites/default/files/publications/
Strategic_Principles_for_Securing_the_Internet_of_Things-
2016-1115-FINAL....pdf>.
[GSMA] "GSMA IoT Security Guidelines and Assessment",
<http://www.gsma.com/connectedliving/future-iot-networks/
iot-security-guidelines>.
[ISO88021X]
ISO/IEC/IEEE, "Telecommunications and exchange between
information technology systems - Requirements for local
and metropolitan area networks - Part 1X: Port-based
network access control".
[ISOIEC23941]
ISO/IEC, "IoT management and control device control
protocol".
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[RFC3748] Aboba, B., Blunk, L., Vollbrecht, J., Carlson, J., and H.
Levkowetz, Ed., "Extensible Authentication Protocol
(EAP)", DOI 10.17487/RFC3748, June 2004,
<https://www.rfc-editor.org/info/rfc3748>.
[RFC4120] Neuman, C., Yu, T., Hartman, S., and K. Raeburn, "The
Kerberos Network Authentication Service (V5)",
DOI 10.17487/RFC4120, July 2005,
<https://www.rfc-editor.org/info/rfc4120>.
[RFC4422] Melnikov, A., Ed. and K. Zeilenga, Ed., "Simple
Authentication and Security Layer (SASL)",
DOI 10.17487/RFC4422, June 2006,
<https://www.rfc-editor.org/info/rfc4422>.
[RFC6347] Rescorla, E. and N. Modadugu, "Datagram Transport Layer
Security Version 1.2", DOI 10.17487/RFC6347, January 2012,
<https://www.rfc-editor.org/info/rfc6347>.
[RFC7296] Kaufman, C., Hoffman, P., Nir, Y., Eronen, P., and T.
Kivinen, "Internet Key Exchange Protocol Version 2
(IKEv2)", DOI 10.17487/RFC7296, October 2014,
<https://www.rfc-editor.org/info/rfc7296>.
[RFC7401] Moskowitz, R., Ed., Heer, T., Jokela, P., and T.
Henderson, "Host Identity Protocol Version 2 (HIPv2)",
DOI 10.17487/RFC7401, April 2015,
<https://www.rfc-editor.org/info/rfc7401>.
[RFC8446] Rescorla, E., "The Transport Layer Security (TLS) Protocol
Version 1.3", DOI 10.17487/RFC8446, August 2018,
<https://www.rfc-editor.org/info/rfc8446>.
[RFC8576] Garcia-Morchon, O., Kumar, S., and M. Sethi, "Internet of
Things (IoT) Security: State of the Art and Challenges",
DOI 10.17487/RFC8576, April 2019,
<https://www.rfc-editor.org/info/rfc8576>.
[ZB] "Zigbee Alliance", 2020, <http://www.zigbee.org/>.
Authors' Addresses
Bin Wang (editor)
Hikvision
555 Qianmo Road, Binjiang District
Hangzhou
310051
China
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Phone: +86 571 8847 3644
Email: wbin2006@gmail.com
Song Liu (editor)
Hikvision
555 Qianmo Road, Binjiang District
Hangzhou
310051
China
Phone: +86 571 8847 3644
Email: achelics@gmail.com
Li Wan (editor)
Hikvision
555 Qianmo Road, Binjiang District
Hangzhou
310051
China
Phone: +86 571 8847 3644
Email: dzwanli@126.com
Jun Li (editor)
CICS-CERT
No.35, Lugu Rd., Shijingshan Dist
Beijing
100040
China
Email: lijun@cics-cert.org.cn
Xing Wang (editor)
Hikvision
555 Qianmo Road, Binjiang District
Hangzhou
310051
China
Phone: +86 571 8847 3644
Email: xing.wang.email@gmail.com
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HaoNan Yan (editor)
Hikvision
555 Qianmo Road, Binjiang District
Hangzhou
310051
China
Phone: +86 571 8847 3644
Email: yanhaonan.sec@gmail.com
Yinghui Xie (editor)
Hikvision
555 Qianmo Road, Binjiang District
Hangzhou
310051
China
Phone: +86 571 8847 3644
Email: 532874282@qq.com
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