Transcript The Future Narrowband Digital Terminal (FNBDT)* * Next

The Future
Narrowband
Digital Terminal
(FNBDT)*
* Next generation signaling protocols for secure
interoperable communications, or everything you
always wanted to know about secure signaling...
but were afraid to ask
(this presentation has notes)
25 April 2002
1
The Global Context
25 April 2002
2
THE MILITARY APPLICATION...
GLOBALSTAR
GPS
DCSC III
GPS
(TO)
T1/FT1
BACKBONE
HOST
NATION
MILITARY
CONTROLLED
SHF
SWITCH
CELL
GATEWAY
MSE/DSRN
25 April 2002
USERS
SINGLE FOOTPRINT ... 700 MILES
3
The Homogeneous PSTN
Telephone Network
EVOLVING DIGITAL
BACKBONE AND SS7
ISDN
ACCESS LINES
ANALOG CELLULAR
ACCESS LINES
25 April 2002
4
Standards Based Secure Voice
Elcrovox1
(Phillips)
National
Keys for
Spendex40M
STU-IIB
(Motorola)
UK Keys
For STU-II
Spendex40M
(Siemans)
National
Keys for
TCE 500
Homogeneous
Telephone
Network
NATO Keys
for TCE 500
TCE 500
(NORCOM)
TCE 500
(NORCOM)
NATO Keys
for Elcrovox1
UK Keys
for Elcrovox1
National
Keys for
Elcrovox1
NATO Keys
for TCE 500
Elcrovox1-4D
(Phillips)
NATO Keys
for TCE 500
TCE 500
Spendex40M
(Siemans)
With a NATO standard, manufacturers could build NBSV-II
secure voice products that interoperated with each other.
25 April 2002
5
Secure Voice Equipment - No Standards
US Keys
For STE
UK Keys
For BRENT
STE
US Keys
For STU-II
STU-IIB
ISDN
BRENT
National
Keys for
TopSec-703
TopSec-703
Homogeneous
Telephone
Network
TCE 500/B
Analog
Cellular
UK Keys
for Elcrovox1
Elcrovox1-4D
(Phillips)
NATO
Keys for
TCE 500/B
STU-III
AMPS
TCE 500/B
STU-III
US Keys
For STU-III
Secure communications were achieved with many,
non-interoperable families of secure telephone systems.
25 April 2002
6
Getting Worse
US Keys
For STE
US Keys
For STU-II
STE
UK Keys
For BRENT
ISDN
STU-IIB
BRENT
National
Keys for
TopSec-703
Expanding
Telephone
Network
TopSec-703
TCE 500/B
GSM
Analog
Cellular
TopSec-GSM
NATO
Keys for
NSK 200
TIGER
NSK 200
STU-III
AMPS
NATO
Keys for
TCE 500/B
STU-III
US Keys
For STU-III
TCE 500/B
Interoperability is not possible, even if keys are shared.
25 April 2002
7
Today’s Fragmented Infrastructure
ISDN
IP
INTERNET
IP
IP PHONE
NETWORK
BACKBONE
TDM, ATM, IP
TRI-TAC &
MSE
MSS
GSM
CDMA
TDMA
TETRA,
APCO-25,
iDEN
Analog
Cellular
TACTICAL DIGITAL
RADIOS
The Era of a Fragmented Communications Network
25 April 2002
8
The Interoperability Problem
• The homogeneous communications network of the past is a
fragmented collection of bearers and protocols
- Many different network types and voice coders
- Multiple backbones: CDM, TDM, ATM, IP
- Multiple community of service providers
• It is increasingly difficult to transmit secure voice over the
traditional voice network
- data services must be an integral component of design
• One architecture for secure voice/data is difficult, but multiple
architectures are impractical
Multiple unique solutions for each bearer network are impractical at best
So, NATO must work together to define a common architecture
25 April 2002
9
FNBDT Potential for Interoperability
• Secure Global Interoperability
– Using multiple networks of interest
– End terminals possibly on different networks, and connected by
intermediate disparate networks
– End-to-end connections are defined by concatenation of network
segments, problems and characteristics
• Satisfy both NATO and individual national objectives
– Flexibility to include new applications & different cryptographic
suites
– Flexibility to allow the standard to evolve with technologies and
capabilities
• Challenge is to design and build a family of interoperable
FNBDT products to a single architectural standard
25 April 2002
10
Conceptual Approach
• Create architecture that enables interoperability
– Nations build products to an interoperable architecture
• Accommodate network challenges for both 2 party and N party
– secure voice and data
– secure call setup and secure net key distribution
•
Define common interoperable modes of operation
– STANAG-4591 MELPe vocoder for 2400 bps operation
– Blank & Burst protocol for 2-party and n-party secure voice
maintains crypto sync and 2400 bps operation
• Allows late entry into communications stream
• Allows bridging deep fading or severe jamming conditions
• Complete crypto sync information transmitted every 3 B&B frames
• Provide negotiation to select or identify common modes, and
cryptographic systems
25 April 2002
11
Basic Signaling Approach - Summary
• FNBDT signaling is application layer signaling inserted into
the data input capability of any network end point
• Transported over concatenated network segments
• Requiring only a data path from transmitter to receiver(s)
• Blank & Burst secure voice and data signaling designed for
N-party net broadcast and 2-party communication
• Additional point-to-point signaling designed for key
management, rekey, or other pt-pt communication
• May use asynchronous character transmission
FNBDT point-to-point signaling designed for interaction with a KMS,
2-party call setup, key agreement, and other point-to-point
communications will be described in the companion briefing next.
25 April 2002
12
FNBDT Signaling - Interoperability
Time
Capabilities
Messages
Parameters/Certificate
Messages
F(R)
Messages
Messages Defined by Product
Vendors for Type 4 Cryptography
Cryptosync
Messages
?
MELP
Voice
G.729D
Voice
Reliable Transport
Async Data
New Message for
National Cryptography
New
Message
Electronic Rekey
Other FNBDT
Applications
To communicate securely, both FNBDT products
must have FNBDT signaling, 2400 bps STANAG-4591,
Reliable Transport, and use common key material,
key exchange algorithms, and traffic cryptography.
25 April 2002
New Applications
13
Secure 2400 bps MELP Voice B&B
Blank & Burst Transmission Format
START OF SECURE VOICE
APPLICATION
SOM
V13
V14
V38
V39
V63
ACK*
EOM
V15
V71
**
FILLER
START
SM1
V2
V27
V23
V24
SM2
V26
V47
V48
SM3
V50
V51
V72
SM4
V74
V75
54-bit encrypted MELP
vocoder frame every 22.5 ms
25 April 2002
SUPERFRAME (540 ms)
V83
V3
V11
V12
V35
V36
V37
V59
V60
V61
V62
V84
V85
V86
etc.
Sync Management frame
replaces every 24th MELP
vocoder frame
14
Secure MELP Voice Super-frame
Blank and Burst
54
54
Sync
Management
MELP Vocoder
Frame #2
16
PN
0x7AC8
16
Partial Long
Component
54
MELP Vocoder
Frame #3
14
Short
Component
8
CRC
...
54
54
MELP Vocoder
Frame #23
MELP Vocoder
Frame #24
<=Bits
<=Field
<=Bits
<=Field
Defined appropriately for the cryptographic suite
The entire State Vector is
transmitted in 3 Sync
Management frames
The Blank & Burst format maintains the 2400 bps rate of the MELP
vocoder. Thus, FNBDT may be used on 2400 bps synchronous
channels. Full state vector transmitted every 1620 ms.
25 April 2002
15
Reliable Transport Design Considerations
• Data in this layer must be reliably transported
• Standard protocols (HDLC, TCP/IP, etc.) considered
– Overhead too high for lower rate narrowband channels
– Performance issues at assumed channel error rates
– Appropriate for networks with lower BER
• Settled on hybrid ARQ/FEC technique
– ACK/NAK with selective and block (go back to “N”) repeat
– High rate FEC with CRC for ‘error management’
– 127-frame sliding transmit window
25 April 2002
16
Simplified FNBDT Protocol Layers
Point-To-Point Reliable Signaling
FNBDT CALL
SETUP
FNBDT
Signaling
with KMS
Other Point-toPoint Signaling
FNBDT Traffic
Signaling
MELP
VOICE
Encryption
MESSAGE LAYER
BLANK & BURST
RELIABLE TRANSPORT
HOST NETWORK
DATA SERVICE
Additional FNBDT point-to-point
signaling designed for interaction with
KMS, 2-party call setup, key agreement,
and other pt-pt communications.
25 April 2002
HOST NETWORK
DATA SERVICE
Blank & Burst was designed
for use with MELP in N-party
secure net broadcast and 2party secure communications.
17
Simplified FNBDT Protocol Layers
Point-to-point Reliable Signaling
FNBDT
Signaling
with KMS
(Rekey)
Other Point-toPoint Functions
FNBDT CALL
SETUP
FNBDT Traffic
Signaling
MELP
VOICE
Encryption
MESSAGE LAYER
BLANK & BURST
RELIABLE TRANSPORT
HOST NETWORK
DATA SERVICE
FNBDT Call Setup develops the traffic
key (and more ….) using reliable pointto-point communication techniques.
25 April 2002
FNBDT Traffic Signaling
is used for point-to-point
and net broadcast.
18
FNBDT and Military Radio Concepts
MELP
Crypto
Other Common Applications
B&B Frame
Common Protocols
Protocols Common to
HF and VHF
Protocols Common to
UHF and EHF
Other
Protocols
HF
Protocols
& Error
Control
VHF
Protocols
& Error
Control
UHF
Protocols
& Error
Control
EHF
Protocols
& Error
Control
Other
Protocols
& Error
Control
HF
Radio
VHF
Radio
UHF
Radio
EHF
Radio
Other
Radio
Radio planning may start with different radio systems at the
physical layer, and seek to harmonize systems at higher
layers. FNBDT is “harmonized” at the application layer.
25 April 2002
19
FNBDT Secure Communications
FNBDT No. 1
FNBDT No. 2
MELP
MELP
Encryption
Encryption
B&B Frame
B&B Frame
Relay
Relay
PSTN/ISDN
Octets
Protocols defined
by Signaling Plan
V.32
Protocols defined by Networks
V.32
Protocols defined
by Signaling Plan
FNBDT is an application.
FNBDT doesn’t care what networks are used to transport the data.
The FNBDT MELP application transmits only 2400 bps of data.
25 April 2002
20
FNBDT and 2-Party Secure Voice
STE with
FNBDT
on Ship
Radio
Radio
IWF
Mil Satellite Link
IWF
CDMA
IWF
PSTN
CDMA
MS with
FNBDT
IWF
ISDN
Phone
With
FNBDT
ISDN
GSM MS
with FNBDT
IWF
GSM
PSTN
GSM
MS With
FNBDT
IWF
CDMA MS
with FNBDT
NATO
UK
U.S.
KMS
Norway
KMS
KMS
KMS
FNBDT
Adapter
HF Radio &
HF Modem
HF Radio &
HF Modem
FNBDT
Adapter
Now let’s look into some of the detail for a secure call between
CDMA and GSM versions of an FNBDT secure cellular phone.
25 April 2002
21
FNBDT and N
2-Party Secure Voice
STE with
FNBDT
on Ship
IWF
Radio
Radio
IWF
IWF
Mil Satellite Link
PSTN
ISDN
Phone
With
FNBDT
ISDN
IWF
GSM MS
with FNBDT
IWF
CDMA MS
with FNBDT
NATO
UK
U.S.
KMS
Norway
KMS
KMS
KMS
FNBDT
Adapter
HF Radio &
HF Modem
PSTN
HF Radio &
HF Modem
N-Party Net
Media
CDMA
MS with
FNBDT
IWF
GSM
MS With
FNBDT
FNBDT
Adapter
HF Radio &
HF Modem
FNBDT
Adapter
For
communication,
a KMS the
provides
keys.
KeyN-Party
Management
Systems provide
keyingtraffic
material.
FNBDT secure traffic signaling allows terminals on
TEKs
for secure
nets areterminals
pre-positioned
or acquired
through
In 2-party
calls, FNBDT
use “Call
Setup” signaling
different networks to participate in a secure net.
point-to-point
withand
an element
the KMS.
to negotiate a communication
cryptographic suite
a secureoftraffic
mode.
25 April 2002
22
2-Party Call Setup
Time
Capabilities
Messages
Parameters/Certificate
Messages
F(R)
Messages
Messages Defined by Product
Vendors for Type 4 Cryptography
Cryptosync
Messages
?
MELP
Voice
G.729D
Voice
Electronic Rekey
New Message for
National Cryptography
New
Message
Reliable Transport
Async Data
Other FNBDT
Applications
Call Setup negotiations may select other
applications and alternate cryptographic suites.
Let’s see how this is done.
25 April 2002
New Applications
23
Signaling Extensions - New Keysets
Time
Capabilities
Messages
Parameters/Certificate
Messages
F(R)
Messages
Messages Defined by Product
Vendors for Type 4 Cryptography
Cryptosync
Messages
?
MELP
Voice
G.729D
Voice
Reliable Transport
Async Data
New Message for
National Cryptography
New
Message
But, common cryptography doesn’t mean that all
FNBDTs have the same cryptography. Source IDs
allow Allied and National Keysets and Cryptography
to be included in the Capabilities Message.
25 April 2002
Electronic Rekey
Other FNBDT
Applications
New Applications
24
Signaling Extensions - New Messages & Apps
Time
Capabilities
Messages
Parameters/Certificate
Messages
F(R)
Messages
Messages Defined by Product
Vendors for Type 4 Cryptography
Cryptosync
Messages
?
MELP
Voice
G.729D
Voice
Reliable Transport
Async Data
New Message for
National Cryptography
New
Message
Electronic Rekey
Other FNBDT
Applications
New messages can be defined.
New applications can be defined.
These can be defined privately using Source IDs,
or publicly in shared documentation.
25 April 2002
New Applications
25
Interoperability and Extensions - Summary
• In the past - Interoperability was not generally achievable
– Basic designs were different
– Private national implementations  unique designs
– Interoperability was denied with incompatible designs
• FNBDT provides future interoperability
– Basic FNBDT designs can be the same
– Private national implementations  unique FNBDT extensions
– Interoperability can still be denied using different national key
material
FNBDT is designed to permit -Global, international interoperability
And private, national implementations
--The best of both worlds
25 April 2002
26
FNBDT- The Key to Interoperability
FNBDT
FNBDT
FNBDT
STE
FNBDT
FNBDT
FNBDT
FNBDT
FNBDT
GSM
ATM
TCP/IP
ISDN
HF
LMR
DSL
AEHF
Many Media – Many Protocols
One Application
25 April 2002
27
Secure VoIP to PSTN
Handset
Handset
FNBDT
Emulator
Gateway
IP
Phone
FNBDT
Gateway
IP Network
Data
Modem
FNBDT
Emulator
CS Network
or
Router
IP
Phone
FNBDT
Gateway
Voice
Modem
POTS
Phone
FNBDT on Mixed Networks: Secure VoIP to PSTN
25 April 2002
28
Secure Net Broadcast on Wireless LAN/IP
Terminal 1
Communications Manager
Terminal 2
802.11b
Wireless
LAN
Key
Material
Terminal 3
Security Manager
SNBS Configuration with a
“Communications Manager
Terminal 4
FNBDT Secure Net Broadcast on Wireless LAN
25 April 2002
29
Discussion/
Questions?
25 April 2002
30
FNBDT
-------------------Miscellaneous Examples
25 April 2002
31
Wired/Wireless Implementation Strategy
Mobil Satellite Service
Iridium, Globalstar, ICO
STE
Iridium
STU-III
Gateway
Digital Cellular
iDEN (NEXTEL)
GSM
Digital
Dispatch
PSTN
Analog
Analog Cellular
CipherTAC 2000
Digital Cellular
CDMA
Tactical
MSE/TRI-TAC
JTR
STU-III
Deployable
LMR
Cell
Tactical STE
Net Broadcast
25 April 2002
32
CDMA to GSM Secure Voice
IWF
IWF
PSTN
GSM
MELP
MELP
Encryption
Encryption
B&B Frame
CDMAChars
MS
Async
with FNBDT
TCP
TCP
IP
IP
SNDCF
SNDCF
PPP/IS-99
PPP/IS-99
RLP
IS-95
CDMA MS
with FNBDT
B&B Frame
FNBDT Secure Voice Data
CDMA
Air Link
GSM Air
Link
Protocols
GSM
Air
Link
RLP
IS-95
GS Chars
MS
Async
With FNBDT
Relay
Relay
V.32
CDMA Fixed Plant
PSTN
or ISDN
V.32
GSM Fixed Plant
GSM
Air Link
GSM MS
With FNBDT
FNBDT Secure Voice Data may be sent over many network segments.
The connection shown here uses CDMA, PSTN and GSM networks.
25 April 2002
33
CDMA to GSM Secure Voice
IWF
IWF
PSTN
MELP
Data
GSM
MELP
Data
FNBDT Data or Secure Data
Encryption
Msg Layer
Encryption
Msg Layer
R.
B&B
Transport
Frame
R.
B&B
Transport
Frame
Async Chars
TCP
TCP
IP
IP
SNDCF
SNDCF
PPP/IS-99
PPP/IS-99
RLP
IS-95
CDMA MS
with FNBDT
Relay
Relay
CDMA
Air Link
GSM Air
Link
Protocols
GSM
Air
Link
RLP
IS-95
Async Chars
V.32
CDMA Fixed Plant
PSTN
or ISDN
V.32
GSM
Air Link
GSM Fixed Plant
GSM MS
With FNBDT
FNBDT “Reliable Transport” protocols provide reliable
data communication in point-to-point connections.
25 April 2002
34
STE (Ship) to Secure GSM
IWF
Radio
Radio
IWF
IWF
PSTN
Mil Satellite Link
MELP
MELP
Crypto
Encryption
B&B Frame
B&B Frame
Relay
V.120
V.120
Relay
Relay
Satellite
Link
Protocols
Satellite
Link
Protocols
GSM
Air
Link
RF thru
Satellite
ISDN
STE with
FNBDT
ISDN
RF
IWF: ISDN to Satellite
PSTN
RF
V.32
IWF: Satellite to PSTN
Async Chars
GSM
Air
Link
GSM Air
Link
Protocols
V.32
GSM Fixed Plant
GSM Handset
However complex the connection, FNBDT data flows across
the digital path, established between the two end points.
25 April 2002
35
STE (Ship) to Secure GSM
IWF
Radio
Radio
IWF
IWF
PSTN
Mil Satellite Link
MELP
MELP
Crypto
Encryption
FNBDT Secure Voice Data
B&B Frame
Relay
V.120
V.120
Relay
Relay
Satellite
Link
Protocols
Satellite
Link
Protocols
GSM
Air
Link
RF thru
Satellite
ISDN
STE with
FNBDT
ISDN
B&B Frame
RF
IWF: ISDN to Satellite
PSTN
RF
V.32
IWF: Satellite to PSTN
Async Chars
GSM
Air
Link
GSM Air
Link
Protocols
V.32
GSM Fixed Plant
GSM Handset
FNBDT signaling accommodates any path underneath.
Voice quality will depend on the delays and errors in the path.
25 April 2002
36
GSM to N-Party Media
IWF
N-Party
Net Media
ISDN
MELP
Encryption
B&B Frame
N-Party Net Communications Media
Relay
Async Chars
Relay
Input
GSM Air
Link
Protocols
HF
Link
Protocols
e.g.
GSM
Air
Link
GSM
Air Link
GSM Handset
Output #1 Output #2 Output #3
ISDN
V.32
V.32
HF Radio
GSM Fixed Plant
PSTN
PSTN
Net broadcast devices or radios can distribute FNBDT
secure traffic. If the FNBDT net recipient has the key, late
entry or not, it can obtain crypto sync and the clear traffic.
25 April 2002
37
CDMA to GSM Secure Call Setup
IWF
PSTN
Capabilities-B
FNBDT
CALL
SETUP
IWF
GSM
Capabilities-A
Parameters/Certificate-A
Parameters/Certificate-B
F(R)-A
F(R)-B
CryptoSync-B
FNBDT
CALL
SETUP
CryptoSync-A
MSG Layer
MSG Layer
(FNBDT Call Setup Messages)
R. Transport
R. Transport
HOST NETWORKS
DATA SERVICE
MS - A
(CDMA)
MS - B
(GSM)
Before 2-party secure voice traffic starts, FNBDT Call Setup
Application Messages are exchanged using the FNBDT
Application Reliable Transport and Message Layer Protocols.
25 April 2002
38
Capabilities Message Format
Header Information Field
15
Header Information
2
Message ID Information
Source ID
MID Value
2
Modes
Length
2 for each entry
Operational
Modes List
2
1
Message
Length
Message
Version
2
Keysets
Length
1
As Required
Keysets List (Optional)
1
Initiator
Signaling
Negotiation Plan Version
<=Octets
<=Field
8
Terminal ID Information
Source ID
ID Value
All messages contain the MID, Message Length, and Message Version fields.
The “Source ID” is 5-bits. It shows who defined the field.
25 April 2002
39
Capabilities Message Format
Operational Modes List Field
15
Header Information
2
Modes
Length
2 for each entry
Operational
Modes List
2
First Operational Mode ID (Preferred)
Source ID
Operational Mode ID
….
2
Keysets
Length
As Required
Keysets List (Optional)
2
Last Operational Mode ID
Source ID
Operational Mode ID
<=Octets
<=Field
<=Octets
<=Field
Terminals send a list of operational modes they would like to use.
Operational modes with Source ID = 0x00 are defined in FNBDT-210.
Operational modes with Source ID = 0x03, e.g., would be defined elsewhere.
25 April 2002
40
Capabilities Message Format
Key sets list with new source IDs
15
2
2 for each entry
2
As Required
Header Information
Modes
Length
Operational
Modes List
Keysets
Length
Keysets List (Optional)
2
….
As Required
2
First Keyset Type (Preferred)
Source ID
Keyset Type
Parameters
Length
2
New Keyset Type
0x17
New Keyset Type
….
<=Octets
<=Field
Parameters List (Optional)
2
Parameters
Length
2
Last Keyset Type
Source ID
Keyset Type
….
As Required
Parameters List or as
Defined for New Keyset Type
2
Parameters
Length
….
As Required
<=Octets
<=Field
Parameters List (Optional)
The Keysets List can include keysets with different Source IDs.
After a Source ID is assigned, e.g., 0x17, Keyset Types can be
defined and included in the Capabilities Message.
25 April 2002
41
FNBDT Basic Signaling
Parameters/Certificate Message
Time
Capabilities
Messages
Parameters/Certificate
Messages
F(R)
Messages
Messages Defined by Product
Vendors for Type 4 Cryptography
Cryptosync
Messages
?
MELP
Voice
G.729D
Voice
Reliable Transport
Async Data
New Message for
National Cryptography
New
Message
Electronic Rekey
Other FNBDT
Applications
Parameters/Certificate Messages are used to
exchange content associated with the selected
cryptographic suite.
25 April 2002
New Applications
42
FNBDT Basic Signaling
F(R) Message
Time
Capabilities
Messages
Parameters/Certificate
Messages
F(R)
Messages
Messages Defined Product
Vendors for Type 4 Cryptography
Cryptosync
Messages
?
MELP
Voice
G.729D
Voice
Reliable Transport
Async Data
New Message for
National Cryptography
New
Message
Electronic Rekey
Other FNBDT
Applications
F(R) Messages are used to exchange
content associated with the selected
cryptographic suite.
25 April 2002
New Applications
43
FNBDT Basic Signaling
Cryptosync Message
Time
Capabilities
Messages
Parameters/Certificate
Messages
F(R)
Messages
Messages Defined by Product
Vendors for Type 4 Cryptography
Cryptosync
Messages
?
MELP
Voice
G.729D
Voice
Reliable Transport
Async Data
New Message for
National Cryptography
New
Message
Electronic Rekey
Other FNBDT
Applications
Cryptosync Message are exchanged as the
last step before starting secure traffic.
25 April 2002
New Applications
44