The Advanced Technology Demonstration Network (ATDnet)


Overview
--------
The Advanced Technology Demonstration Network (ATDnet) is a recently 
inaugurated high performance networking testbed in the Washington D.C. 
area. It is intended to be representative of possible future Metropolitan 
Area Networks. Established by ARPA to enable collaboration among Defense 
and other Federal agencies, ATDnet has a primary goal to serve as an 
experimental platform for diverse network research and demonstration 
initiatives. Emphasis is on early deployment of emerging Asynchronous Transfer 
Mode (ATM) and Synchronous Optical Network (SONET) technologies.

There are six participating Federal agencies. The Advanced Research Projects 
Agency (ARPA) and the Defense Information Systems Agency (DISA) serve as 
co-chairs of the ATDnet Program. Other members are the Defense Intelligence Agency 
(DIA), the National Aeronautics and Space Administration (NASA), the Naval 
Research Laboratory (NRL), and the National Security Agency (NSA). 

The ATDnet concept is to interconnect several agency sites with high speed 
fiber optic transmission media and to overlay this media with SONET and ATM 
protocols. The initial deployment will be at OC-48 data rates (approximately 
2.5 billion bits/second, also referred to as 2.5 gigabits/second) but is designed 
to scale upwards to technology-limited data rates. 

Pair-wise and multiple party research initiatives and experiments are planned 
over the lifetime of the testbed. Experimental testing of the bitways and a 
diversity of service and applications experiments are intended to gain insight 
into the potential of this new performance level. 

The base experimental period for ATDnet is two years. Installation commenced in 
December 1993. Initial SONET ring connectivity was completed on 2 April 1994. 
Initial Operating Capability (IOC) for ATM services was achieved in early May 
1994. 

ARPA further envisions use of the ATDnet physical infrastructure to support proof 
of concept experiments and demonstrations which prototype aspects of an enhanced 
National Information Infrastructure (NII) and its use in the context of future 
Defense Information Infrastructures. Plans include engaging the National Institute 
for Science and Technology (NIST) in research collaborations to facilitate 
extending the ATDnet model and associated experiments agenda into broader 
commercial initiatives and to help refine evolving standards.

Program Objectives
------------------
The ATDnet program was initiated to enable prototype deployments and evaluations 
of wide bandwidth, associated hardware and software, protected communications, 
advanced network services, and bandwidth-demanding applications. A primary, 
long-range goal is to facilitate reliable, affordable, and secure information 
services which serve to demonstrate technologies and methods appropriate for the 
emerging National Information Infrastructure (NII). 

Government-industry teaming has been arranged to enable and support leading-edge 
metropolitan and regional-scale networking activities over an extended period. 
ATDnet is intended to mutually benefit current and future telecommunications 
industry service providers, high performance networking hardware and software 
vendors, and a diverse Government consumer base. 

It is further intended to facilitate technology transition in support of DoD 
efforts such as the Global Grid concept of worldwide Command, Control, 
Intelligence, and combat support systems sustained by end-to-end information flow. 

Specific objectives include: 

1. acquire early experience with advanced communications and network technologies, 
primarily ATM and SONET, but also including direct fiber access 
2. help industry and Government assess and better understand characteristics of a 
suitable technology base and the needs of NII-scale public networks 
3. establish an adaptable, extensible environment for evaluating developmental 
and commercial products and services in realistic, user-stressing deployments 
4. experiment with operation, maintenance, and management of these technologies and 
services as the testbed is expanded to include multiple vendors, multiple 
technologies, and links to other networks and commercial service providers 
5. deploy and assess a diversity of information security approaches 
6. enable and evaluate innovative applications, particularly those requiring 100 
Megabit/sec to 1 Gigabit/sec to the end user 
7. feed results back into planning, engineering, and development efforts directed 
toward next-generation product and service offerings 
8. support technology transition to DoD and the broader Federal High Performance 
Computing and Communications (HPCC) program 

Responsibilities
----------------
ATDnet was established as an ARPA high performance networking research project 
in cooperation with the other participating agencies. ARPA has lead responsibility 
for overall technical coordination of the ATDnet research agenda. DISA is 
coordinating SONET network management and providing system engineering support. 
NRL is performing ATM network administration and configuration support. Each 
participating agency is responsible for its local network infrastructure and its 
experimental program. Program management and experiments are coordinated through 
the ATDnet Steering Committee, co-chaired by ARPA and DISA. Industrial participation 
will be via voluntary participation or subscribed through contractual actions by the 
participating agencies. 

Physical Infrastructure
-----------------------
ATDnet is supported with a physical infrastructure provided by Bell Atlantic,
a regional Bell Operating Company (RBOC). 

Funded by ARPA, a contract was awarded to Bell Atlantic in November 1993 
following a competitive solicitation via ARPA Broad Area Announcement 
BAA 93-02, Multiple-Technology Network Testbed. The base period two year award 
was $1.9 million per year and a two year optional extension is offered at $1.4 
million per year. 

The SONET/ATM network testbed employs a physical ring topology for SONET transport 
among the six Government sites. ATM switching connectivity will be evaluated in 
multiple configurations, including a logical star topology and a ring 
configuration paralleling the SONET ring. 

Bell Atlantic is provisioning ATDnet as a diversely routed, survivable SONET ring 
with SONET add/drop multiplexers (ADM) installed at the customer premises and at 
Bell Atlantic's Operations Support Center in Silver Spring, Maryland. The SONET 
ring is initially configured with two fibers but an additional pair of fibers will 
be added to interconnect each of the transport nodes within the first year. 

Northern Telecom Inc. S/DMS OC-48 Transport Nodes serve as the ADMs. Each OC-48 ADM 
complies with SONET standards to transport high capacity data streams of up to 2.5 
Gigabits/second over fiber optic media. The S/DMS OC-48 can 
route service and protection lines over physically and geographically separate 
facilities and can sense and automatically restore interrupted service. 

Each Government site will be provisioned with four-fiber, OC-48 SONET service to 
its ADM. Such a facility is referred to as a Metropolitan Point of Presence (MPOP). 
Initially, each on-site MPOP will be further provisioned with two OC-3c (155 million 
bits/second) service connections to on-premise, Government- furnished ATM switches. 
Deployment of OC12c (622 million bits/second) ATM services is expected in 1995. 

In ATDnet Phase I, FORE Systems FORErunner ASX-100 switches will be employed at 
every site. Deployment of ATM resources from other vendors is planned, using 
standards-compliant signaling, to experimentally validate interoperability and 
potential for national-scale, switched virtual circuit (SVC) public ATM environments. 

On-premise routing and local distribution of ATM and SONET traffic is the individual 
responsibility of each participating agency. Typical configurations may include ATM 
service to scientific/engineering workstations, database and file servers, high 
performance computers, and high resolution and 3D display devices. 

Experiments Agenda
------------------
Experimental programs are planned by each agency. Some experiments may involve only 
two sites but most will involve multiple participants. ARPA's research focus includes 
deployment trials of ATM signaling, network management, and traffic congestion 
management. These will be performed in conjunction with Bell Communications Research 
Inc. (Bellcore) under subcontract to Bell Atlantic. 

High speed secure networking techniques will be assessed through SONET link encryption 
and ATM key-agile encryption experiments planned with technical support from NSA and 
NRL. A diversity of information security measures and technologies will also be fielded 
and evaluated. 

A variety of Defense experiments and demonstrations are anticipated over the lifetime 
of the testbed. These are intended to improve understanding of outstanding issues 
and alternative approaches and help model the technology and applications base 
appropriate to a Defense Information Infrastructure, including a DII with global 
reach. Demonstrations and evaluations of multi- vendor ATM switch and interface 
interoperability will be featured throughout the evaluation process. 

As part of its HPCC Program, ARPA intends to leverage its investment in the ATDnet 
by engaging a diverse experimental community which will extend beyond the initial 
six agencies. Through strategic partnerships with a variety of Governmment 
and commercial organizations, ARPA hopes to explore conceptual and technology building 
blocks leading toward an enhanced National Information Infrastructure (NII). 
A major goal is to evaluate and help evolve long haul, commercial, end-to-end 
ATM services. 

Applications under consideration, as means of thoroughly evaluating network 
features and performance and as proof of concept of the applications themselves, 
include telemedicine, crisis management, computational science, and scientific 
visualization. Partnerships with ARPA will entail research agreements. 
Connectivity will not be supported as an alternative to acquiring commercially 
available services. 

In collaboration with NASA and the Advanced Communications Technology Satellite 
(ACTS) Program, an ACTS High Data Rate (HDR) Terminal facility will be 
interconnected at NASA's Goddard Space Flight Center. A number of planned ACTS 
experiments, remote regions demonstrations, and cross country interconnects will 
eventually be supported. 

In collaboration with the National Institute for Science and Technology (NIST), 
extension of the ATDnet model to commercial initiatives and in support of standards 
work is planned. These activities, including rigorous field evaluations of 
interoperability among commercial products, will be performed cooperatively 
with vendor participants. Results will be fed back to vendor and user communities 
through publications, human networking, and active participation in standards 
bodies, such as the ATM Forum. 

Other initiatives, including interconnecting to optical networking testbeds, 
will be considered for experimentally evaluating and validating concepts and 
prototypes at the very high end of networking technology. 

