Post on 16-Sep-2020
Visualizing NISTIR 7628, Guidelines for Smart Grid Cyber Security
Matthew Harvey; Daniel Long; Karl Reinhard University of Illinois Urbana-Champaign, Dept. of Electrical Engineering
Abstract— The National Institute of Standards and Technology Interagency Report (NISITR) 7628, Guidelines for Smart Grid Cyber Security, provides an analytical framework that stakeholders can use to develop effective Smart Grid related characteristics, risks, and vulnerabilities. NISTIR 7628 spans more than 600 pages and is densely packed with technical information drawn from multiple disciplines, which to many readers is difficult to broadly conceptualize and apply. This paper explores methods for visualizing the complexities of NISTIR 7628’s cyber security guidelines for the nascent Smart Grid and aiding readers to better synthesize the information presented.
I. INTRODUCTION The United States and other advanced industrial countries around the world have embarked upon a long term effort to modernize their electric power infrastructures. This modernization effort includes applying advanced digital technologies to systems to expand communications and control over very large systems to achieve ever increasing efficiency while maintaining very high reliability. The broad application of digital technologies is accompanied by increased exposure to malicious attacks upon the power grid's digital infrastructures. As the digital infrastructure expands, the exposure to and consequences of compromise also expand.
In August of 2010, the National Institute of Standards and Technology (NIST) Computer Security Division published NISTIR 7628, Guidelines for Smart Cyber Security, which expands upon the Smart Grid cyber security principles published in NIST's 2010 Special Publication 1108, NIST Framework and Roadmap for Smart Grid Interoperability Standards. NISTIR 7628 synthesizes the input of more than 500 stakeholder representatives from the private sector (including utilities, vendors, manufacturers, and electric service providers), various standards organizations, academia, regulatory organizations, and federal agencies. The guidelines represent power, computer, information technology, and telecommunications industry perspectives. The document is a first effort to develop a technical, analytical framework needed to inform individuals and organizations responsible for addressing cyber security for Smart Grid systems and its constituent hardware and software components. The document is envisioned as a first step in evolutionary series of documents that will produce standard protocols, interfaces, and technical specifications needed for a secure Smart Grid.
The document focuses exclusively on the cyber-security aspects and does not address physical security requirements.
II. NISTIR 7628
A. NISTIR Diagrams NISTIR 7628 conceptualized the power grid at the higest
level as being composed of seven Domains: marketing, operations, sevice provider, bulk generation, transmission, distribution, and customer as seen in Fig. 1. A Smart Grid domain is a high level grouping of orgainizations, buildings, individuals, systems, devices with similar objectives or functions.
Fig. 2 shows 46 actors that comprise the seven domains. Actors are devices, systems, or programs that make decisions and exchange the information necessary for the Smart Grid to function. This actors list is intended to be comprehensive, but not all inclusive, as this model represents diverse real-world organizations that are uniquely purposed and organized . The Logical Reference Model show in Fig. 3 depicts 130 logical interfaces (interactions between actors. The obvious challenge posed by this representation’s complexity is for users to translate its high level abstractions into implementable policies and procedures on their organizations information processing systems (hardware, software, network, etc.)
To aid this synthesis, NISTIR 7628 identifies 22 logical
Fig. 1 Interactions of Actors in Different Smart Grid Domains through Secure Communications Flows [1]
Submitted for publication. Author copy – do not redistribute.
interface categories that group logical interfaces based upon similar attributes affecting cyber security requirements; the logical interface categories are listed and described in Table 2-2. The grouping criteria include the three traditional Information Assurance dimensions: confidentiality, integrity,
and availability. Other criteria include domain and logical interface information content. Each logical interface can be thought of as a layer in a three dimensional representation. As an example, Fig. 4 provides a graphical depiction of Logical
Fig. 2 Composite High-level View of the Actors within Each of the Smart Grid Domains [1]
Fig. 3 Logical Reference Model [1]
Interface 6, which shows the interfaces between control systems (actors) in organizations in 3 domains.
In addition to the Logical Interface Categories defined in Chapter 2, NISTIR identifies 10 architecturally significant Use Cases that involve different actor and logical interface sets, which have similar complexity and graphical representations. These Use Cases include: advance metering architecture (AMI), Demand Response, Customer Interfaces, Electricity Market, Distribution Automation, Plug-in Hybrid Electric Vehicles (PHEV), Distributed Resources, Transmission Resources, Regional Transmission Operations / Independent System Operators (RTO/ISO), Operations, and Asset Management.
Over the course of 3 years of association with the TCIPG Project and studying NISTIR 7628, we have observed that the document was prepared by experts from three very disparate disciplines: power system engineers, computer and network engineers, and information technologist. There are relatively few experts in these disciplines with overlapping knowledge that bridges the gaps between these disciplines. Consequently, for most readers, the task of making sense of the very detailed and often unfamiliar information is quite daunting.
As a team, we have detailed knowledge of power systems but less knowledge of computer engineering and information management technologies. Therefore, our interest is developing a resource that dramatically accelerates the process of assembling data and information to facilitate synthesizing the complex ideas and relationships necessary to improve cyber security. We believe innovative approaches to visualizing NISTIR 7628’s content would be a big step forward. Further, the user must be able define and adapt the
visualizations appropriate to his own knowledge base and purpose. We also envision the user being able to leverage other resources to seamlessly assemble other information appropriate to their purpose.
III. VISUALIZING NISTIR 7628 Our research vision is to create user controllable visual
representations of the information in NISTIR 7628 to enable cyber security. The interactive interface would enable the user to organize information to provide insights that would otherwise be difficult to reach; this includes controlling the content and detail of information presented. For instance, we envision aiding the identification of common requirements across different Logical Interface Categories and Use Cases by displaying only that information. We also envision aiding the identification of common requirements across different Logical Interface Categories and Use Cases by displaying only that information. We also envision being able to pull-up and drill-into detailed information not a part of the current view – and open and close other related information as needed.
Our first small step to achieving this vision was to explore ways to stack select logical interface categories as distinct data layers. For example, consider the stacked Logical Interface Categories shown in Fig. 5 – an oblique visualization of several logical interface categories from pages taken directly from the document. This is helpful to illustrating the concept, but not very practical from productive use. We have developed two applications to explore implementing our ideas: 1) a web-based HTML application and 2) a MATLAB-based application leveraging 3D graphing capabilities. A. HTML Web Page Visualization
The HTML-based visualization creates a data layer for each of the 22 logical interface categories; See Fig. 6. Users select the interface layers of interest on the list of 22 interface layers. The selected layers are displayed stacked from the straight-on perspective. The user sees the selected overlapping actors and their interfaces. The data layers can easily be toggled on and off with a mouse click making commonalities
Fig. 5 Logical Interface Category 6, Interface between controls in different organizations [1]
Fig. 4 Stacked Logical Interface Categories [1]
and differences easy to identify. The web page’s stacked depiction focuses the user’s effort on the data without the tedium of thumbing through 50 pages in the document.
The web page visualization proved to be a good first step. However, from the outset, we know that it would sacrifice some information in the NISTIR’s Logical Interface Category diagrams not easily captured with this approach. For example to see more detail about the interface between two actors, a user would still refer back to the paper document. The absence of the third dimension in the visualization made it difficult for the user to track which actors and interfaces were associated with each interface layer. B. MATLAB Visualization
Our efforts to create the 3D representation using MATLAB were much more complex. The actors and interfaces for each logical interface category are assigned coordinates in the x-y plane. The logical interface categories are assigned coordinates on the z axis; see Fig. 3. Like the HTML model, interface categories of interest can be selected and stacked to focus upon the logical interface layers of interest. An attractive feature of the MATLAB representation is the graphical representation can be rotated in the three axes to gain the best view of the relationships of interest. The biggest feature this model has is the unique ability to rotate the model and visualize it from every angle.
Fig. 7 shows the top layer of the visualization model as represented in MATLAB, the actors portrayed are in the similar locations and color coded to the NISTIR 7628 layouts to minimize confusion as much as possible. The MATLAB
tool allows a unique element to be added to model, which is a three dimensional layer that allows users to see the depth of the NISTIR 7628, something that has never been modeled before.
As well as the depth included in the MATLAB model, the information about each connection and relationship can be stored in the tool and accessed with a simple click of the button. This will allow people to understand and grasp a much larger amount of information with the simplicity of an application. Lacking in the MATLAB model is the clarity within a few aspects. Labeling the current model proved to be quite challenging. We found labels that work from a straight-on perspective can be quite difficult to read from other vantage points and create clutter that obscures important details.
We have presented the tool at several conference events with industry, government, and academic participants – and received very encouraging feedback. C. NetAPT Visualization
NISTIR 7628 provided a conceptual construct for understanding the actors and their interaction. However, the NISTIR 7628 paradigm can provide misleading impressions about the physical implementations of the power grid’s cyber systems. The Network Access Policy Tool (NetAPT) developed at the Information Trust Institute; University of Illinois at Urbana-Champaign provided a contracting graphical view of the actors and their interfaces. NetAPT ingests firewall rule information and uses it to generate a
Fig. 6 HTML Model
graphical depiction – a depiction based upon actual system connections and less upon the conceptual functions captured in NISTIR 7628. Fig. 8 provided an example of a prototype power providers system. Now, this depiction has a much different structure than the NISTIR 7628 paradigm would produce. Both representations are valid. This poses interesting lines of investigation leveraging one representation against the other to gain insights that might otherwise not be apparent.
IV. FUTURE EFFORTS While our efforts to date have produced interesting and
useful representations, we recognize that our progress is far from our envisioned functionality. Through our work to-date, we have gained an appreciation for the significant challenges involved.
In the near term, we are seeking off-the-shelf applications that can be adapted to our purposes. Immediate objectives include current and the following desired capabilities to
Label graphical features and easily accommodate interactive perspective changes
Easily zoom-in and pan-out
Increase available information content, while affording the user robust displayed content control
Automatically generate graphic layouts that are both useful and appealing form alternate perspectives
Automatically ingest data to minimize the level of effort required to create, organize, and maintain the underlying “data stores”
A. Conclusions With daily reports of attacks, there is an urgent need to
broadly improve the power grids cyber security posture. The diversity and complexity of the measures environment. Consequently, it is very important that the efforts be placed against the most dangerous threat and vulnerability combinations. This drives the urgent need to understand the requirements established in documents like NISTIR 7628, which are extremely complex. We have demonstrated first steps to producing a graphical depiction that aids synthesizing key insights into the requirements. We have also refined our vision for an application to aid synthesizing complex cyber security information.
REFERENCES [1] NISTIR 7628: Guidelines to Smart Grid Cyber Security, NISTIR 7628,
2010. [2] NetAPT Access Policy Tool. Web. Available:
https://www.perform.illinois.edu/netapt/
Fig. 7 MATLAB Model
Fig. 8 TCIPG NetAPT Cyber Network Representation of Utility [2]
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eter
ing
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ng /
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ity
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k O
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29
NIS
TIR
762
8 G
uide
lines
for S
mar
t Grid
Cyb
er S
ecur
ity v
1.0
– A
ug 2
010
2.3.
1Lo
gica
l Int
erfa
ce C
ateg
orie
s 1—
4
Logi
cal I
nter
face
Cat
egor
y 1:
Inte
rfac
e be
twee
n co
ntro
l sys
tem
s an
d eq
uipm
ent w
ith h
igh
avai
labi
lity,
and
with
com
pute
and
/or b
andw
idth
con
stra
ints
Logi
cal I
nter
face
Cat
egor
y 2:
Inte
rfac
e be
twee
n co
ntro
l sys
tem
s an
d eq
uipm
ent w
ithou
t hi
gh a
vaila
bilit
y, b
ut w
ith c
ompu
te a
nd/o
r ban
dwid
th c
onst
rain
ts
Logi
cal I
nter
face
Cat
egor
y 3:
Inte
rfac
e be
twee
n co
ntro
l sys
tem
s an
d eq
uipm
ent w
ith h
igh
avai
labi
lity,
with
out c
ompu
te o
r ban
dwid
th c
onst
rain
ts
Logi
cal I
nter
face
Cat
egor
y 4:
Inte
rfac
e be
twee
n co
ntro
l sys
tem
s an
d eq
uipm
ent w
ithou
t hi
gh a
vaila
bilit
y, w
ithou
t com
pute
or b
andw
idth
con
stra
ints
Logi
cal i
nter
face
cat
egor
ies 1
thro
ugh
4 co
ver c
omm
unic
atio
ns b
etw
een
cont
rol s
yste
ms
(typi
cally
cen
traliz
ed a
pplic
atio
ns su
ch a
s a S
CA
DA
mas
ter s
tatio
n) a
nd e
quip
men
t as w
ell a
s co
mm
unic
atio
ns b
etw
een
equi
pmen
t. Th
e eq
uipm
ent i
s cat
egor
ized
with
or w
ithou
t hig
h av
aila
bilit
y. T
he in
terf
ace
com
mun
icat
ion
chan
nel i
s cat
egor
ized
with
or w
ithou
t com
puta
tiona
l an
d/or
ban
dwid
th c
onst
rain
ts. A
ll ac
tiviti
es in
volv
ed w
ith lo
gica
l int
erfa
ce c
ateg
orie
s 1 th
roug
h 4
are
typi
cally
mac
hine
-to-m
achi
ne a
ctio
ns. F
urth
erm
ore,
com
mun
icat
ion
mod
es a
nd ty
pes a
re
sim
ilar b
etw
een
logi
cal i
nter
face
cat
egor
ies 1
thro
ugh
4 an
d ar
e de
fined
as f
ollo
ws:
Inte
rfac
e D
ata
Com
mun
icat
ion
Mod
e
–N
ear R
eal-T
ime
Freq
uenc
y M
onito
ring
Mod
e (m
s, su
bcyc
le b
ased
on
a 60
Hz
syst
em) (
may
or m
ay n
ot in
clud
e co
ntro
l act
ion
com
mun
icat
ion)
–H
igh
Freq
uenc
y M
onito
ring
Mod
e (2
s 6
0 s s
can
rate
s)
–Lo
w F
requ
ency
Mon
itorin
g M
ode
(sca
n/up
date
rate
s in
exce
ss o
f 1 m
in, f
ile
trans
fers
)
Inte
rfac
e D
ata
Com
mun
icat
ion
Type
–M
onito
ring
and
Con
trol D
ata
for r
eal-t
ime
cont
rol s
yste
m e
nviro
nmen
t (ty
pica
l m
easu
rem
ent a
nd c
ontro
l poi
nts)
–Eq
uipm
ent M
aint
enan
ce a
nd A
naly
sis (
num
erou
s mea
sure
men
ts o
n fie
ld e
quip
men
t th
at is
typi
cally
use
d fo
r pre
vent
ive
mai
nten
ance
and
pos
t ana
lysi
s)
–Eq
uipm
ent M
anag
emen
t Cha
nnel
(rem
ote
mai
nten
ance
of e
quip
men
t)
The
char
acte
ristic
s tha
t var
y be
twee
n an
d di
stin
guis
h ea
ch lo
gica
l int
erfa
ce c
ateg
ory
are
the
avai
labi
lity
requ
irem
ents
for t
he in
terf
ace
and
the
com
puta
tiona
l/com
mun
icat
ions
con
stra
ints
for
the
inte
rfac
e as
follo
ws:
Ava
ilabi
lity
Req
uire
men
ts –
Ava
ilabi
lity
requ
irem
ents
will
var
y be
twee
n th
ese
inte
rfac
es
and
are
driv
en p
rimar
ily b
y th
e po
wer
syst
em a
pplic
atio
n w
hich
the
inte
rfac
e su
ppor
ts
and
not b
y th
e in
terf
ace
itsel
f. Fo
r exa
mpl
e, a
SC
AD
A in
terf
ace
to a
subs
tatio
n or
pol
e-to
p R
TU m
ay h
ave
a H
IGH
ava
ilabi
lity
requ
irem
ent i
n on
e ca
se b
ecau
se it
is su
ppor
ting
criti
cal m
onito
ring
and
switc
hing
func
tions
or a
MO
DER
ATE
to L
OW
ava
ilabi
lity
if su
ppor
ting
an a
sset
-mon
itorin
g ap
plic
atio
n.
30