Internet Engineering Task Force                                Hal Folts 
INTERNET DRAFT                            National Communications System 
Expires August 1, 2002                                  Februaqry 1, 2002
 
 
       Emergency Telecommunications Service in Evolving Networks 
                 <draft-folts-ieps-white-paper-01.txt> 
 
 
Status of This Memo 
 
This document is an Internet-Draft and is in full conformance with all 
provisions of Section 10 of RFC2026 
 
Internet-Drafts are working documents of the Internet Engineering Task 
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Copyright 
 
Copyright (c) Internet Society 2001.  All rights reserved.  Reproduction 
or translation of the complete documents, but not of extracts, including 
this notice, if freely permitted. 
 
Abstract 
 
This white paper presents the functional requirements, features, and 
objectives for the Emergency Telecommunications Service (ETS) in newly 
emerging telecommunication networks. The ETS is an extension of the 
International Emergency Preference Scheme (IEPS) of the ITU-T 
Recommendation E.106 [1] and includes additional provisions for 
multimedia services through an packet-based telecommunications 
environment. The preferential features of the ETS will only apply to 
severe congestion conditions due to extremely high traffic loads and 
extensive failure of basic infrastructure. ETS is not required under 
normal operating conditions and when adequate capacity is available to 
support all traffic. Efforts are underway in the national standards 
bodies and International organizations to identify, establish, and apply 
a comprehensive family of ETS standards for new packet-based networks. 
This Internet-Draft supercedes an earlier Internet-Draft, draft-folts-
ohno-ieps-considerations-00.txt> [2] 
 
1. Introduction 

The purpose of the Emergency Telecommunications Service (ETS) is to 
facilitate emergency recovery operations for restoring the community 

                                                                     1
                      Emergency Telecom. Service         December 2001 
 
infrastructure and for returning the population to normal living 
conditions after serious disasters and events, such as floods, 
earthquakes, hurricanes, and terrorist attacks. The ETS will be provided 
through shared resources from the public telecommunications 
infrastructure that is evolving from a basic circuit-switched 
configuration of today's conventional telephone networks to an Internet-
based, packet-switched technology providing a richness of communication 
capabilities. The timely establishment of an effective ETS has been 
given significant urgency as a result of the September 11 terrorist 
attacks in the United States. 
 
Many challenges and considerations need to be addressed in defining and 
establishing the functional capabilities for the ETS in the emerging 
packet-based telecommunications services. This paper presents an 
overview of the basic requirements, features, and concepts for ETS that 
packet-based telecommunication and third-generation (3G) mobile networks 
are capable of providing and that must receive attention during the 
process of the convergence of these technologies. Specific solutions are 
not offered, but this paper is intended to stimulate innovative thinking 
and productive discussion in industry standards bodies leading to 
development, establishment, and deployment of appropriate standards for 
the evolving telecommunications services.



Disaster situations can occur any time, any place unexpectedly. These 
events often significantly damage the community infrastructure and 
severely disrupt daily living. Recovery requires rapid response by local 
authorities, immediate reaction from utility service providers, and 
support from medical, construction, fire, and police resources. 
Effective communications are essential to facilitate the myriad 
activities for coordinating lifesaving activities concurrent with 
reestablishing control in the disaster area. Following a disaster, 
immediate response operations focus on saving lives, protecting 
property, and meeting basic human needs. 

2. ETS Operational Requirements 
 
A US Government working group recently identified fourteen basic 
functional requirements for the future ETS. These requirements are
listed in the table below and represent the objectives that need to be
fulfilled for national security and emergency preparedness (NS/EP)
in the ETS.  
                        
================================================================ 
NS/EP                   
Telecommunication       
Services                
Functional              
Requirements                    Description 
================================================================ 
a. Enhanced Priority   Services supporting NS/EP missions must 
Treatment              be provided priority treatment over other 
                       traffic. 
---------------------------------------------------------------- 
b. Secure Networks     Networks must have protection against 
 
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                      Emergency Telecom. Service         December 2001 
 
                       corruption of, or unauthorized access to, 
                       traffic and control, including expanded 
                       encryption techniques and user 
                       authentication, as appropriate. 
---------------------  ----------------------------------------- 
c. Non-Traceability    Selected users must be able to use NS/EP 
                       services without risk of usage being 
                       traced (i.e., without risk of user or 
                       location being identified). 
---------------------  ----------------------------------------- 
d. Restorability       Should a disruption occur, services must 
                       be capable of being reprovisioned, 
                       repaired, or restored to required service 
                       levels on a priority basis. 
---------------------  ----------------------------------------- 
e. International       Services must provide access to and 
Connectivity           egress from international carriers. 
---------------------------------------------------------------- 
f. Interoperability    Services must interconnect and 
                       interoperate with other selected 
                       government or private facilities, 
                       systems, and networks. 
--------------------------------------------------------------- 
g. Mobility            The communications infrastructure must 
                       support transportable, redeployable, or 
                       fully mobile communications (e.g., 
                       personal communications service, 
                       cellular, satellite, high frequency 
                       radio). 
---------------------------------------------------------------- 
h. Ubiquitous Coverage Services must be readily accessible to 
                       support the national security leadership 
                       and inter- and intra-agency emergency 
                       operations, wherever they are located. 
---------------------------------------------------------------- 
i. Survivability/      Services must be robust to support 
   Endurability        surviving users under a broad range of 
                       circumstances, from the widespread damage 
                       of a natural or man-made disaster up to 
                       and including nuclear war. 
---------------------------------------------------------------- 
j. Voice Band Service  The service must provide voice band 
                       service in support of presidential and 
                       other communications. 
---------------------------------------------------------------- 
k. Broadband Service   The service must provide broadband 
                       service in support of NS/EP missions 
                       (e.g., video, imaging, web access, 
                       multimedia). 
---------------------------------------------------------------- 
l. Scaleable Bandwidth NS/EP users must be able to manage the 
                       capacity of the communications services 
                       to support variable bandwidth 
                       requirements. 
---------------------------------------------------------------- 
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                      Emergency Telecom. Service         December 2001 
 
M. Affordability       Services must leverage network 
                       capabilities to minimize cost (e.g., use 
                       of existing infrastructure, commercial 
                       off-the-shelf technologies, services). 
---------------------------------------------------------------- 
n. Reliability/        Services must perform consistently and 
   Availability        precisely according to their design 
                       requirements and specifications, and must 
                       be usable with high confidence. 
================================================================ 
 
These fourteen functional requirements are discussed in this white 
paper. Several of these are elaborated upon in more detail in Section 4 
providing considerations for the eleven ETS features and objectives. The 
other requirements are addressed by text presenting the many concepts 
that are involved in the development of a comprehensive and effective 
ETS. The /x/ in the text identifies the Functional Requirement in the 
above table that is being addressed in this paper. 

Public telecommunication services are universally available, deployed by 
a massive infrastructure throughout most nations, except in the most 
remote and unpopulated regions. These critical telecommunications 
resources, therefore, must be depended upon by the emergency responders 
for supporting the organization and coordination of initial, as well as 
ongoing, recovery activities. It is possible to realize readily these 
capabilities by leveraging the resources that are ubiquitous and most 
likely to be immediately available any place, any time /h/. This 
includes the use of wireless services as mobile networks expand their 
coverage /g/. Dedicated or special government telecommunications 
resources, on the other hand, do not generally have the immediate global 
reach to be responsive initially to disaster events.
 
Two Recommendations of the International Telecommunication Union, 
Telecommunication Standardization Sector (ITU-T) present the basic 
requirements for international emergency telecommunications. ITU-T 
Recommendation E.106, Description of an International Emergency 
Preference Scheme [1], applies to telephony services provided by the 
Public Switched Telephone Network (PSTN), Integrated Services Digital 
Network (ISDN), and Public Land Mobile Network (PLMN). ITU-T Draft 
Recommendation F.706, Service Description for an International Emergency 
Multimedia Service (IEMS) [3], applies to all modes of 
telecommunications service, including telephony, over the newly emerging 
telecommunication networks, including the packet-based Internet Protocol 
(IP) technology and 3G mobile networks. The ETS can be used both in 
national and international contexts and includes the provisions of the 
IEPS and the IEMS. 



Conventional circuit-switched telecommunications services are rapidly 
evolving to a connectionless packet-switched technology. Wireless 
technology is also evolving toward the new 3G capabilities for seamless 
provisioning of services over and across the heterogeneous fixed and 
mobile networks. A substantial transition period is underway as these 
technologies converge. As a result, there will be many critical issues 
of transition and interoperability to address /f/. The newly emerging 

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                      Emergency Telecom. Service         December 2001 
 
technologies will provide greatly enhanced capabilities that can be 
leveraged and can benefit emergency recovery operations during serious 
disaster situations. The Packet-based packet technology provides a very 
new environment that must be leveraged for providing effective and 
economical public telecommunications services for supporting ETS 
capabilities.
 
When a disaster event strikes, the public telecommunications 
infrastructure generally sustains damage, experiences excessive traffic 
loads, and is subject to external interference that may severely limit 
the ability for response and recovery activities to communicate. 
Therefore, special provisions to facilitate effective communications for 
the emergency activities are necessary. This includes priority 
establishment and processing of communications through the 
telecommunication resources that remain available /a/. ETS traffic needs 
to receive preferential use of the surviving capacity of the impacted 
network.
 
3. ETS Features and Objectives 
 
A fully comprehensive ETS needs to have a richness of capabilities to 
support a variety of operational requirements for emergency recovery 
forces. The following is a list of specific features that could 
potentially facilitate communications for disaster recovery activities:
 
   A. Selection of multimedia and telephony services /j/ /k/ 
   B. Rapid authentication of authorized ETS users /b/ 
   C. Security protection of ETS traffic /b/ /c/ 
   D. Preferential access to telecommunications facilities /a/ 
   E. Preferential establishment of ETS communications /a/ 
   F. Preferential routing of ETS traffic /a/ 
   G. Preferential use of remaining operational resources for ETS 
      traffic /a/ 
   H. Preferential completion of ETS traffic to destination /a/ 
   I. Optional preemption of nonemergency traffic /a/ 
   J. Allowable degradation of service quality for ETS traffic /l/ /n/ 
   K. Interchange of critical telecommunications service management 
      information /d/ /n/ 
    
Not all of these features may be immediately possible, practical, or 
available universally. The above list focuses on the basic capabilities 
that need to be addressed and developed. These capabilities could 
greatly facilitate effective and timely recovery operations during 
emergency events. This paper will discuss these features in detail. 
Many nations do not have any emergency capability today except for their 
public telecommunications infrastructure in its present state without 
any of the special features listed above. In the United States, the 
Government Emergency Telecommunications Service (GETS) supports 
emergency recovery operations. However, it only provides priority 
establishment and routing of telephone calls through the public switched 
telephone network (PSTN) for specifically authorized users who expect to 
be involved in emergency recovery operations. GETS fulfills the basic 
functional requirements of ITU-T Recommendation E.106. 


The ETS also has international aspects. Disaster situations are often 

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                      Emergency Telecom. Service         December 2001 
 
regional and involve multiple nations /e/. In these cases, disaster 
recovery assets from multiple nations may be necessary to respond to one 
specific event. Also, in the increasingly "global" world, many nations 
often provide support for recovery operations for emergency disasters 
contained within the borders of another country. ETS traffic, therefore, 
needs to receive favorable treatment at international gateways and 
within national networks providing an ETS. /a/
 
The emergence of new telecommunications technologies and their 
application for telecommunication services in the evolving 
telecommunication networks provides great promise for the realization of 
an enhanced, comprehensive, and effective global ETS. ITU-T Draft 
Recommendation F.706 [3] presents requirements for multimedia services 
to support emergency operations. Not only will voice telephony services 
need to continue, the inclusion of broadband services like video 
broadcast and conferencing but also will be beneficial /k/. In addition, 
narrowband capabilities such as instant messaging and presence as well 
as Email would facilitate short, rapid command and control information 
interchange, and would enhance recovery operations. This will be 
particularly useful during periods of limited bandwidth availability and 
as a last resort to communicate when conditions become most severe. 
Currently, prominent international standards bodies are developing a new 
telecommunication infrastructure that is expected to be deployed over 
the next several years. It is imperative that the specifications of 
these networks include support for the functional requirements of a 
comprehensive ETS before equipment and systems are designed, 
manufactured, and deployed. None of these new specifications shall cause 
change or impairment of operation of existing emergency capabilities or 
the basic packet-switched infrastructure. With the necessary 
capabilities built into the new telecommunications infrastructure, the 
ETS can then become readily available with a diversity of services for 
emergency response operations through execution of service level 
agreements (SLAs) between service customers (SCs) supporting recovery 
operations and the telecommunications service providers (SPs). It will 
then be possible to offer the service more expediently and to avoid the 
expense of deploying special capabilities or retrofitting existing 
systems. The SC will then pay the appropriate tariffs for actual 
services received. /h/
 
The availability of the ETS for authorized users could also be specified 
in an SLA. The ETS could always be available for use at any time and at 
any place in a specific network. This would allow fast-response access 
immediately when the disaster strikes. Some networks, on the other hand, 
may only activate the ETS upon declaration of an emergency by the 
appropriate authority. This could cause a serious delay in the ability 
for response and recovery forces to communicate effectively. Some 
inbetween capability could also be possible, where a basic preferential 
service would always be available and then enhanced features could be 
activated upon declaration of an emergency.
 


The transition to packet-based and 3G mobile services for new 
telecommunication services will involve a number of issues, one of which 
is to ensure orderly and transparent continuance of the basic E.106 
emergency preference capabilities. During the convergence period, the 

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                      Emergency Telecom. Service         December 2001 
 
different schemes for interworking between the two technologies must be 
considered. For example, voice calls from the telephone or mobile 
network may transit voice-over-IP links and then terminate in either the 
telephone network or directly in a packet-based network /f/. The 
European Telecommunications Standards Institute (ETSI) describes four 
different scenarios of interoperation [4]. Because of the variety in 
configurations, it is necessary to establish the interfaces for 
interworking between the signalling systems of today's telephone 
networks and the new call control and signalling protocols of evolving 
telecommunication networks. This needs to be accomplished without 
negatively impacting the fundamental operation or infrastructure of 
existing and future packet-based networks. As new networks with the 
basic emergency service priority capabilities come into being, it will 
be important to provide enhanced services by leveraging the new 
capabilities of the emerging packet-based networks./k/
 
As indicated earlier, ubiquitous telecommunications resources that 
provide services to the general population provide the basis for readily 
available capabilities for an ETS./h/ Since public telecommunication 
resources are normally at hand, emergency operations activities do not 
have to wait for deployment of special facilities. However, as emergency 
operations get underway, supplemental capabilities could also be of 
significant benefit, particularly when public telecommunication 
resources become seriously stressed and limited. Therefore, it would be 
desirable to have a telecommunications infrastructure that can be 
readily integrated with transportable, redeployable, and fully mobile 
facilities, such as personal communications service, cellular, 
satellite, and high frequency radio /f/ /g/. Interoperability and 
interfaces among selected government or private facilities, systems, and 
networks would be very beneficial /f/. It is also highly desirable that 
ETS resources be as robust as possible to support surviving users under 
a broad range of circumstances, including widespread damage during 
natural or man-made disasters /i/. 

4. ETS Considerations 
 
There are a number of important considerations that need to be studied 
in order to best use the connectionless packet technology for the ETS in 
the new telecommunication capabilities. The advantages and inherent 
characteristics of the packet-based technology need to be leveraged and 
not impeded. It will be necessary to define and establish the 
appropriate quality, availability, and reliability of service guidelines 
for the various modes of multimedia communications. There are many 
formidable challenges that need to be addressed in the fulfillment of 
the functional requirements that have been established in ITU-T 
Recommendations E.106 [1] and F.706 [3]. They serve as the principal 
objectives to meet in provisioning a truly comprehensive and effective 
ETS. More specific considerations in seeking the necessary mechanisms 
and solutions for ETS are:
 


    A. Selection of multimedia and telephony services /k/ - The basic 
       service defined in ITU-T Recommendation E.106 [1] is telephony 
       as provided by the public switched telephone networks (PSTN), 
       integrated services digital networks (ISDN), and public land 

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                      Emergency Telecom. Service         December 2001 
 
              mobile networks (PLMN). The emergence of integrated voice/data 
       services of evolving telecommunication and 3G mobile networks, 
       based on packet switching technology, need to not only support 
       telephony services but also provide a variety of enhanced modes 
       of communication including instant messaging and presence, 
       Email, web and database access, video, and teleconferencing. 
       These additional services can also be used effectively for 
       emergency communications. This will enable emergency recovery 
       operations to have a comprehensive menu of supporting 
       communication capabilities.
 
    B. Rapid authentication of authorized ETS users /b/ - The ETS is 
       intended for use only by authorized users involved with 
       emergency recovery operations. The appropriate authority of each 
       nation or community would authorize these designated users. Upon 
       initiation of an emergency communication request, an
       authentication process needs to verify the user's identity to 
       protect the telecommunication resources against excessive use 
       and abuse during an emergency situation. In the United States, a 
       personal identification number (PIN) similar to the application 
       of credit card calling in the PSTN currently authenticates 
       authorized GETS users. For the future ETS, it is desirable to 
       establish an innovative method for a streamlined and rapid user 
       authentication in the emerging telecommunication and 3G mobile 
       networks. The passing of authentication as the ETS communication 
       travels across networks also needs to be addressed.
 
    C. Security protection of ETS traffic /b/ /c/- Security is a major 
       concern with the evolution of packet-based networks. In addition 
       to the many basic security provisions already under 
       consideration, ETS has additional security provisions that 
       require special attention. Security protection is necessary to 
       prevent unauthorized users from accessing scarce resources 
       needed to support emergency operations. This includes such 
       threats as spoofing, intrusion, and denial of service. In 
       addition, the identity and location of certain authorized users 
       of the ETS need protection.
 


    D. Preferential access to telecommunications facilities /a/ - There 
       are a number of ways to access telecommunication resources for 
       obtaining ETS capabilities. These include PSTN wire line, 
       wireless, satellite, cable, digital subscriber line (DSL), and 
       optical fiber. There will be a significant advantage for an 
       emergency operations user to be able to obtain access to these 
       various telecommunications services on a priority or 
       preferential basis. This will enable more rapid initiation of 
       emergency communications. 
      
       Today the PSTN service has no general provision for signalling 
       priority access requests. However, specially marked lines or 
       specifically provisioned "off-hook" services could provide 
       preferential access, but that would only be by line and location, 
       not per ETS request. There is currently no provision for 
       conveying a priority dial tone or service initiation via general 

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                      Emergency Telecom. Service         December 2001 
 
       
       access from a conventional telephone instrument. Dial tone comes 
       a demand basis from a limited selection of ports and heavy 
       traffic conditions can delay access if demand consumes the supply 
       of ports. Therefore, a provision for preferential access to 
       services in packet-based telecommunication networks is a 
       capability that requires consideration.
 
       As with the PSTN dial-tone ports, cellular services have a 
       limited number of channels in each cell to accept call initiation 
       from an end device. When a disaster event occurs in a particular 
       local area, floods of call attempts generally occur. This 
       severely reduces the probability of access. Therefore, a priority 
       access service for designated users or end devices is also needed 
       for cellular services. 


       Appropriate technical mechanisms inherent in the infrastructure 
       need to be applied to enable preferential access via the various 
       methods for initiation of ETS communications. It is imperative 
       that authorized emergency operations have the ability to respond 
       rapidly to disaster events in a timely and efficient manner. 

    E. Preferential establishment of ETS communications /a/ - A 
       communication may consist of a single unit of information 
       transiting from source to destination or of a flow of 
       information via a series of packets or stream of data. In 
       technologies that support connection mode operation, an end-to-
       end path for the communication to transit is established upon 
       entry of the address, or telephone number, of the destination 
       terminal. In connectionless mode operation, individual packets 
       may transit the network over different paths. When the total 
       communication involves a series of packets, they are assembled 
       and processed together at the destination. 
      
       Emergency communications must have a high degree of assurance for 
       successfully reaching the destination, regardless of the networks 
       they transit. Therefore, the ETS traffic needs to be uniquely 
       identified and receive preferential treatment over nonemergency 
       traffic. This provides a priority service for authorized 
       communications in the ETS. In a PSTN, once a connection is 
       established, the call effectively is "hard-wired" in the form of 
       a circuit-switched connection and does not require continuance of 
       preferential status. In a connectionless packet network 
       environment, however, it is necessary to maintain the ETS 
       identification for all respective packets. ETS identification 
       also needs to be conveyed to each of the transit networks, 
       regardless whether they support ETS. Telecommunication service 
       providers (SP) must be able to identify and prioritize emergency 
       communications according to their service level agreement with 
       the service customer (SC) and other SPs. 



    F. Preferential routing of ETS traffic /a/ - Routing of packets is 
       a continuing process for an instance of communication until the
       session has reached completion. As indicated above, the priority 
       status and identification of emergency communications must be 

Folts                   Document, July 2, 2002                       9
                      Emergency Telecom. Service         December 2001 
               
       maintained until session termination. If the path being followed
       becomes congested or fails, the network or application layer 
       mechanisms could be applied to dynamically reroute ETS traffic 
       through remaining operational resources. While additional delay 
       may result from the rerouting process, ETS traffic will still 
       have a higher probability of reaching its destination.
  
    G. Preferential use of remaining operational resources for ETS 
       traffic /a/ - During disaster events, infrastructure damage and 
       heavy traffic demand can severely limit public 
       telecommunications. Therefore, ETS traffic needs to have 
       preferential use of the appropriate amount of operational 
       infrastructure required to effectively support recovery 
       operations without impeding the inherent traffic flow throughout 
       the connectionless packet network. To this end, a scheme of 
       preferential treatment needs to be defined that will accommodate 
       various types of priority services for authorized users as well 
       as for general public emergency use (i.e. 911/999/112 emergency 
       calling service). The appropriate balance of traffic flow needs 
       to be maintained to ensure support of emergency traffic while 
       the remaining capacity can be used for nonemergency 
       applications. 



    H. Preferential completion of ETS traffic to destination /a/ - In 
       addition to considering the issue of preferential establishment,
       routing, and maintaining an ETS communication, it is also 
       necessary to establish provisions to facilitate completion of 
       the emergency communication to the destination terminal. When an 
       end terminal can handle multiple sessions, its inherent packet-
       multiplexing feature naturally allows the incoming ETS 
       communication to be delivered. When the terminal device can only 
       handle a single session, such as a cell phone, the user needs to 
       receive an overriding indication of an incoming ETS 
       communication. The destination could then suspend nonemergency 
       communications to free bandwidth for the incoming emergency 
       communication. If preemption were an option, nonemergency 
       communications to the destination could be terminated. Should 
       the destination have "call forwarding" initiated, the network 
       should then continue to reroute and process the emergency 
       communication with preferential treatment to the new 
       destination.
 


    I. Optional preemption of nonemergency traffic /a/-ITU-T draft 
       Recommendation F.706 [3] identifies the process and concept of 
       preemption of non-emergency traffic by ETS traffic. While the 
       concept of preemption typically applies to circuit-oriented 
       communications, its application in connectionless packet network 
       services, if determined viable, needs to be studied and defined. 
       The basic ETS provisions do not include the concept of 
       preemption of nonemergency traffic to free bandwidth and 
       resources for emergency traffic. The intent is to have ETS 
       traffic receive basically preferential treatment. If the
       communication encounters congestion or a blockage, it should be 
       rerouted if possible. Any nonemergency communication in progress 

Folts                   Document, July 2, 2002                      10
                      Emergency Telecom. Service         December 2001 
 
       is normally allowed to continue until completion. However, some
       nations or private networks may allow preemption of nonemergency 
       traffic to enable processing of emergency communications. 
       Therefore, in these cases preemption may be allowed only as an 
       option, which could be invoked as specifically prescribed by 
       that authority.
  
    J. Allowable degradation of service quality for ETS traffic /l/ /n/ 
       -Various levels of quality of service (QoS) are defined for 
       different applications and modes of operation. Each may have 
       multiple classes from the very best QoS to lesser levels. The 
       QoS for different ETS services would typically be designated as 
       the best available to ensure clear clean communications and 
       conveyance of important information. However, when the 
       telecommunication resources are experiencing severe stress, an 
       allowable degradation of QoS could be acceptable. This would 
       occur only when resources have become unavailable to the point 
       that the network cannot support nonemergency traffic and 
       sufficient bandwidth and resources are not available to support 
       the normally acceptable QoS level for emergency traffic. Rather 
       than lose the ability to communicate, emergency operations need 
       to continue to convey critical information, even if with 
       difficulty. Any possibility of getting information through is 
       better than none at all. The ETS needs to continue operation 
       when only "best effort" service is available. Therefore a 
       special or supplemental class of QoS for ETS is necessary to 
       define the conditions and terms for allowable degradation of 
       service. 

    K. Interchange of critical telecommunications service
       management information /d/ /n/ - During emergency operations 
       interaction between the SCs and SPs through sharing of critical
       information related to availability and status of
       telecommunication resources would be beneficial. SCs could
       maintain knowledge of service availability and could provide
       reports to Ps of service problems and failures. SCs could also
       have a view of resource configurations supporting the
       operational needs at hand. SPs would be able to provide reports
       of status and availability of resources, failure points,
       recovery notices, and alerts of lost capabilities. When the ETS
       is only activated during a declared emergency, the SC can
       directly notify the SP on-line to activate the ETS service for
       the area impacted. An effective service management interface
       and a simple data interchange mechanism are needed to provide
       this important capability. 
 
5. Conclusions 
 
The establishment of meaningful standards to make ETS a reality requires 
dedicated cooperation and collaboration among industry and government. 
Initial ETS capabilities, as defined by ITU-T Recommendation E.106 [1] 
exist in some nations today and can be deployed in the basic telephone 
systems that are in place. The evolution of telecommunications 
technology to provide more effective, efficient, and economical /m/ 

Folts                   Document, July 2, 2002                      11
                      Emergency Telecom. Service         December 2001 
 
facilities in emerging packet-based networks provides both a challenge 
in transition and an opportunity to apply greatly enhanced capabilities 
for a national and an international ETS. Many of the ETS requirements 
addressed in this paper may already be satisfied without change or 
addition to existing standards. These capabilities need to be identified 
and their application to the ETS needs to be defined. Where capabilities 
for ETS do not exist, new standards or additions to existing 
specifications in the international standardization process needs to be 
addressed. It is imperative that any specifications include support for 
the functional requirements of a comprehensive ETS before equipment and 
systems are designed, manufactured, and deployed. None of these new 
specifications shall cause change or impairment of operation of existing 
emergency capabilities or to the basic packet-switched infrastructure. 
ETS is multidimensional and includes many critical technical issues as 
well as policy, legal, regulatory, and operational issues that need to 
be addressed. Close cooperation between government and industry will 
lead to timely establishment or identification of meaningful standards 
and deployment of ETS capabilities in the evolving telecommunication and 
3G mobile networks.
 


This document is intended to serve as a basis for discussions and 
development of innovative ideas in standards bodies. The material 
presented will be further refined as a result of continuing work toward 
identifying, establishing, and applying a family of comprehensive 
standards for national and international Emergency Telecommunications 
Services. Please visit www.iepscheme.net and subscribe to the IEPS Email 
list to track the progress of work. 

6. Security Considerations 
 
Ian Brown in another ID presents security considerations for ETS [5].
 


7. Acknowledgements 

Many thanks to Fred Baker, Scott Bradner, Ian Brown, Ken Carlberg, Sean 
Donelan, Jack Garrity, Stu Goldman, Kimberly King, Gary Thom, Jean 
Trakinat, Greg Bain, and Toby Trygar, for their comments on this draft. 
8. Author's Address 
 
Hal Folts, Senior Systems Engineer 
Priority Services - Internet Team, Technology and Programs 
National Communications System 
foltsh@ncs.gov 
+1 703 607-6186 
 
8. References
 
   1. ITU-T, "Description of an International Emergency Preference 
      Scheme", ITU-T Recommendation E.106, March 2000. 

   2. Folts, H., and Ohno, H, " draft-folts-ohno-IEPS-considerations-
      00.txt, June 2000.

3. ITU-T, "Service Definition of an International Emergency Multimedia 

    Folts                   Document, July 2, 2002                      12
                      Emergency Telecom. Service         December 2001 

      Service", ITU-T Draft Recommendation F.706, August 2001. 

   4. ETSI TR 101 300, V2.1.1, "Telecommunications and Internet 
      Protocol Harmonization Over Networks (TIPHON); Description of 
      Technical Issues", October 1999 

   5. Brown, I, "Securing prioritised emergency traffic", Internet 
      Draft, draft-brown-ieps-sec-00.txt, July 2001.
 
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