Technical Considerations for CATV Open Access —continued

4: Ideal Open Access Definition

For the purposes of this white paper, ideal open access provisioning for high-speed data broadband access networks is defined by a set of ideal technical requirements.

For these requirements, subscriber refers to the residential or commercial end user who is receiving a service (e.g. Internet service, IP dial tone service, packet voice service, packet video service, etc.) which is delivered over the broadband access network; service provider refers to the organization or business which is supplying one or more services to the subscriber; and broadband access provider is the owner or operator of the broadband access network last mile facilities to which subscribers are connected and through which services are exchanged between the subscriber and the service provider. The broadband last mile facilities could be a Digital Subscriber Loop (DSL), a CATV plant (concentric pair), a Fiber-To-The-Curb (FTTC) plant, a wireless network, a satellite network, and in some cases combinations of these access methods.

The requirements are labeled as R1 through R12 for reference later in the paper:

• R1: Provider Selection: In the United States, the technical delivery of a high-speed data broadband access facility to a residential home or commercial site allows the subscriber to be provisioned to the service provider of their choice, selected from a set of service providers. For example: high-speed data (i.e. Internet) access and potentially separately for packet voice service provider(s) access. The number of service providers in this set may be from several to upwards of several hundred.
• R2: Multiple Providers: Extends R1a to support multiple service providers selected from a set of service providers and the broadband access device (e.g. cable modem) and facility would allow a subscriber to be served by multiple providers. For example, the work IP service provider for in home telecommuting, simultaneously with an Internet service provider for private non-work related Internet access, and a packet voice provider for voice services, with potential of a different service provider for each enabled phone service.
• R3: Ability to Provide: A service provider is technically able to offer service to their customer via any high-speed data broadband access network that reaches that customer. Actual delivery of services will be dependent on a number of factors including backend network access, access network physical deployment issues, tariffs, quality of service needs, franchise rights, settlement fees, etc.
• R4: Bandwidth Allocation: The broadband access network should support service contracts and provide reserved individual or aggregate data rate to a subscriber or service provider. The allocated bandwidth may be statically provisioned or changed dynamically through signaling with the subscriber or service provider. The broadband access network system should support a range of data rate allocations that may be contracted between the service provider and the subscriber. For example, Internet data access may offer a best effort service with contracted minimum and maximum data rate delivery and/or delay agreements: e.g. 386 KBPS or 1.5 MBPS full duplex Internet data service with or without a Committed Information Rate (CIR)
• R5: Quality of Service: The broadband access network should support specific Quality of Service (QoS) attributes for specific services (e.g. delay, jitter, and error rate) which meet the subscriber's needs of that service. For example, a 64 KBPS constant bit rate with low delay and jitter per off hook packet voice connection while the call is in progress, etc. The Quality of Service required could be statically provisioned or may be changed and negotiated dynamically through signaling with the subscriber or service provider.
• R6: Subscriber Containment: The broadband access network must contain and limit abusive subscribers: a subscriber in one service should not be able to abuse their services so as to interfere with the services being provided to another subscriber in the same or different service; e.g., a large file transfer by one cable modem user should not interfere with the voice call from another cable modem user.
• R7: Provider Containment: The broadband access network must contain and limit abusive service providers; a service provider should not be able to abuse their services so as to interfere with other services or subscribers of other services.
• R8: Link Privacy: In the case of shared media or publicly propagated media, high-speed broadband access networks (e.g. cable television, wireless), communications over that media exchanged between the subscriber premise equipment and the head-end, must employ cryptographic techniques at the data link layer to provide a high degree of privacy for individual sub-scriber communications. Note this is link privacy only to dissuade promiscuous observation by other parties connected to the same shared media, this is not an end-to-end cryptographic solution.
• R9: User Content Preservation: User information contained in packets and packet headers exchanged between the subscriber's premise and the service provider are not altered by the broadband access network or the back end network, except as defined by protocol standards and standards of operation of Internet gateways and routers.
• R10: Provider Address Management: The addresses used by the service (e.g. IP addresses for Internet, phone numbers for packet voice, etc.) are managed by the service provider and not by the broadband access network provider.
• R11: Provider Subscriber Management: The service provider is able to manage their service to the demarcation point associated with the customer premise equipment. For example, the Internet Service Provider (ISP) can manage their service delivery through the broadband access network to the cable modem and be able to troubleshoot to the cable modem Ethernet interface; or a Competitive Local Exchange Carrier (CLEC) can manage a voice over cable service to the RJ11 jack in the cable modem.
• R12: IP Dial Tone Service: The subscriber has the option of obtaining unblocked unrestricted IP packet exchange for any packet submitted to and/or received from the access network according to IP protocol standards and Internet standards for routers and gateways. That is, broadband access network and broadband service provider will not block and/or alter IP packets except according to IP routing standards. The subscriber may be subject to contracted bandwidth allocation restrictions and admission control policies for Quality of Service. It should be noted that most subscribers will want to take advantage of the services and content provided by the cable operator and/or their ISP; e.g. residential subscribers seeking turnkey e-mail, web based content, etc. However, some subscribers will want a plain IP connection (IP Dial Tone) without additional services and features; e.g. sophisticated subscribers, small businesses, larger commercial establishments, etc. Note that it is possible to run versions of open access provisioning with less than this ideal set of requirements.

These ideal requirements do not represent a consensus of definitions used by today's open access providers, nor are they meant to convey an official definition in use by the government or any regulatory agency. They are used here to illuminate and support comparisons of different open access provisioning methods that are discussed within this paper.

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