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diff --git a/doc/rfc/rfc6217.txt b/doc/rfc/rfc6217.txt new file mode 100644 index 0000000..0b807ad --- /dev/null +++ b/doc/rfc/rfc6217.txt @@ -0,0 +1,507 @@ + + + + + + +Independent Submission T. Ritter +Request for Comments: 6217 1 April 2011 +Category: Experimental +ISSN: 2070-1721 + + + Regional Broadcast Using an Atmospheric Link Layer + +Abstract + + Broadcasting is a technology that has been largely discarded in favor + of technologies like multicast. This document builds on RFC 919 and + describes a more efficient routing mechanism for broadcast packets + destined for multiple Local Area Networks (LANs) or Metropolitan Area + Networks (MANs) using an alternative link layer. It significantly + reduces congestion on network equipment and does not require + additional physical infrastructure investment. + +Status of This Memo + + This document is not an Internet Standards Track specification; it is + published for informational purposes. + + This is a contribution to the RFC Series, independently of any other + RFC stream. The RFC Editor has chosen to publish this document at + its discretion and makes no statement about its value for + implementation or deployment. Documents approved for publication by + the RFC Editor are not a candidate for any level of Internet + Standard; see Section 2 of RFC 5741. + + Information about the current status of this document, any errata, + and how to provide feedback on it may be obtained at + http://www.rfc-editor.org/info/rfc6217. + +Copyright Notice + + Copyright (c) 2011 IETF Trust and the persons identified as the + document authors. All rights reserved. + + This document is subject to BCP 78 and the IETF Trust's Legal + Provisions Relating to IETF Documents + (http://trustee.ietf.org/license-info) in effect on the date of + publication of this document. Please review these documents + carefully, as they describe your rights and restrictions with respect + to this document. + + + + + + +Ritter Experimental [Page 1] + +RFC 6217 Regional Broadcast 1 April 2011 + + +Table of Contents + + 1. Introduction ....................................................2 + 2. Terminology .....................................................2 + 3. Limitations .....................................................2 + 4. Physical Layer ..................................................3 + 5. Frame Format in the OSI Model ...................................3 + 5.1. Data Link Layer ............................................3 + 5.2. Network Layer ..............................................3 + 5.3. Transport Layer ............................................4 + 6. Reception .......................................................6 + 7. Datagram Transmission ...........................................6 + 7.1. Chemical Approach to the Atmospheric Link Layer ............6 + 7.2. Location ...................................................7 + 7.3. Physical Layer Conditions ..................................7 + 8. References ......................................................8 + 8.1. Normative References .......................................8 + 8.2. Informative References .....................................8 + +1. Introduction + + RFC 919 [1] defines a method for broadcasting packets to a local + network. It assumes that data link layers support efficient + broadcasting. In the years since RFC 919 was written, Local Area + Networks have grown exponentially in size, and frequently they are + not geographically local. + + This RFC proposes a new data link layer that scales efficiently to a + geographically local network and, depending on visibility, to an + entire Metropolitan Area Network. By using a different transmission + medium, the broadcast traffic does not impact current inter- or + intra-network routed traffic. It also makes use of a widely + available infrastructure that is in use in all major cities and, + surprisingly, rural and under-developed locations as well. + +2. Terminology + + The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", + "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this + document are to be interpreted as described in RFC 2119. + +3. Limitations + + This RFC does not propose solutions to all problems. Just as RFC 919 + was unconcerned with reliability, we also do not guarantee that hosts + receive datagrams sent. Hosts may not receive packets for a variety + of reasons, among them weather conditions, line of sight, sleep + patterns, and distraction. A best-effort delivery approach is taken. + + + +Ritter Experimental [Page 2] + +RFC 6217 Regional Broadcast 1 April 2011 + + + These limitations do impact the usefulness of the proposal, but + organizations serious about distributing information in this fashion + can overcome these obstacles with relatively little difficulty. + +4. Physical Layer + + The physical layer used is made up primarily of nitrogen and oxygen, + at a pressure of 101.3 kilopascal at sea level, but dropping to about + half that pressure at operating altitudes. Microscopic residue or + trace elements may exist in the transmission medium, depending on + local formation properties. + + This residue may include argon, carbon dioxide, neon, helium, + chloride anions, sulfur dioxide, and other molecules occurring at + very low mixtures. It is common for there to be some degree of + gaseous dihydrogen monoxide present. These trace molecules usually + do not impede the broadcast, although further details on datagram + transmission follow. + +5. Frame Format in the OSI Model + + It is always a challenge to design a protocol that allows enough + flexibility for future adaptation while keeping it efficient in size + -- and for this medium, size and complexity of the header are of + particular concern. For this reason, this RFC proposes + recommendations for the Data Link, Network, and Transport Layers. + + Implementations MAY use any protocol that fits their needs for the + Network and Transport Layers. They SHOULD consider how different + protocols may be interpreted by recipients of the message and choose + the most effective protocol available. The protocols defined have + been designed to allow maximum ease of interpretation, so their use + is encouraged. + +5.1. Data Link Layer + + The Data Link Layer is primarily concerned with transmitting + datagrams between adjacent nodes, and it is unnecessary here since we + only support broadcast transmission. Implementers MUST NOT + encapsulate packets in a link layer protocol. + +5.2. Network Layer + + When designing a protocol for the Network Layer, it makes sense to + consider existing protocols in this layer and reference their + strengths and weaknesses. Looking at IPv4/6, we can see their header + structures include several fields unnecessary for our purposes: + + + + +Ritter Experimental [Page 3] + +RFC 6217 Regional Broadcast 1 April 2011 + + + Destination, TTL (Time to Live), DSCP (Diffserv Code Point), ECN + (Explicit Congestion Notification), Hop Limits, and so on. We can + design a much more compact protocol thusly: + + +-------------------------------+-----------------------------+ + | Content | Source | + +-------------------------------+-----------------------------+ + + Figure 1: Layout of the Datagram + + Content - A variable-length field containing the encapsulation of + higher-level protocols. + + Source - The sender of the message. A transmission MUST choose one + of the following representations of the source: + - IPv4 address in dot-decimal notation (e.g., 192.168.1.1) + - IPv6 address in standard notation (RFC 5952 [2]) + - telephone number in E.123 notation + - electronic mail address in E.123 notation + - Uniform Resource Identifier (RFC 3986 [3]) + - geographic address + + The Source field MUST be present -- to send a message anonymously, a + sender MUST use one of the reserved entries of the different types. + Reserved Entries for telephone numbers vary by region; for example, + in North America they are 555-0100 to 555-0199. Reserved entries for + IPv4 (RFC 5735 [4]), IPv6 (RFC 5156 [5]), and URIs (RFC 2606 [6]) may + be found in their respective RFCs. The concept of a region defined + by homogeneous communication characteristics has been put forward + already in [7], so geographic addressing ambiguities may be resolved + by community standards. + + Because the message is sent to a specific geographical region, more + leniency is available in source addressing, but requirements may be + imposed by higher-level protocols. + + We call this protocol the Asynchronous Dumb Visual Exchange of Raw + Transmissions or ADVERT. + +5.3. Transport Layer + + Similar to the Network Layer, a Transport Layer protocol is able to + omit several constructs that are used in existing Transport Layer + protocols. Consider TCP -- sequence, acknowledgement, and many of + the flags are discarded as there will be no SYN, SYN/ACK, or ACK + handshake in a broadcast message. Likewise, fields such as Window + Size and Urgent -- created primarily as a benefit to router + manufacturers -- are unnecessary in this medium. + + + +Ritter Experimental [Page 4] + +RFC 6217 Regional Broadcast 1 April 2011 + + + In fact, in the event of a plain text message, content SHOULD be + embedded directly in the ADVERT Protocol without the need of a + transport protocol. Consider the following packet: + + Content Source + +------------------------------------------------------------+ + | Lobster Dinner - only $14.99 500 Boardwalk, Pt Pleasant | + +------------------------------------------------------------+ + + Figure 2: Example ADVERT Datagram + + For UTF-encoded payloads, one SHOULD use the default UTF-encoding so + the packet is human-readable. This will minimize accidental + misinterpretation. This transmission structure lends itself most + easily to human-parsable messages. + + For messages intended to be responded to by a computer (for example, + binary content), a Transport Layer protocol MUST be used, and an + implementer SHOULD use UDP, as it is one of the more compact + protocols available in this layer. An implementer SHOULD encode the + UDP ports, length, and checksum in base-10 (leading zeros omitted) + and the data in Base64 encoding. The Base64 encoding, combined with + the UDP checksum, resolves ambiguities with trailing whitespace or + non-printable characters. + + The usage of UDP or other protocols that compute a checksum over + source and destination addresses necessitates the use of either an + IPv4 or IPv6 address as the Source in the ADVERT Protocol. The + Destination address 255.255.255.255 MUST be used in the calculation + of an IPv4-based checksum, as it has already been specified as a + local hardware broadcast that must not be forwarded (RFC 919). For + IPv6, the All Nodes link-local multicast destination + FF02:0:0:0:0:0:0:1 MUST be used, defined in RFC 4291 [8]. + + ADVERT Datagram UDP Embedded Sample Data + +-----------------+ +--------+--------+ +--------+--------+ + | | |Src Port|Dst Port| | 0 | 80 | + | | +--------+--------+ +--------+--------+ + | | | Length |Checksum| | 24 | 62670 | + | UDP Packet | +--------+--------+ +--------+--------+ + | | | | | R0VUIC8gSFRUUC8 | + | | | Data | | xLjENCg0K | + | | | | | | + +-----------------+ +-----------------+ +-----------------+ + | Source Address | | Source Address | | 203.0.113.8 | + +-----------------+ +-----------------+ +-----------------+ + + Figure 3: Example of Encapsulating Binary Data in an ADVERT Datagram + + + +Ritter Experimental [Page 5] + +RFC 6217 Regional Broadcast 1 April 2011 + + +6. Reception + + Upon receipt, the datagram should be optically scanned into an + electronically transmittable form, similar to the methods used in RFC + 1149 [9]. If present, any checksums SHOULD be computed and compared + with supplied values. If the checksum does not match, the packet + MUST be discarded. + + Physical layers always have advantages and disadvantages depending on + their condition, maintenance, prevalence, and economic factors; the + atmosphere is no different. The protocols defined herein do not + specify a TTL specifically because it is often out of their control, + and dependent on the conditions present. The intrinsic TTL produces + a curve of error rates where, after time, meaning cannot be + deciphered from the datagram either because of a non-matching + checksum or, in the absence of a checksum (such as the ADVERT + protocol), because of an unintelligible transmission. If the Source + field is sufficiently distinguishable, the recipient MAY contact the + sender for message clarification. RFC 919 is in agreement in stating + that broadcasts MUST NOT be assumed to have been reliably delivered. + + Reconsidering Figure 3, a broadcast HTTP Request is sent, and + recipients should return the request from each of their computer + systems that are listening on the requisite port. It is important to + remember the security implications of the systems' acceptance of data + from unknown senders. It is the responsibility of each organization + to utilize host-protection mechanisms and egress filtering to avoid + exposing their systems to undue risk or exposing internal or NAT-ed + devices. + + Although it may be easy for an operator to silently discard the + packet, it would be inappropriate for a network operator to + unilaterally discard data, in the absence of policy. RFC 1087 [10] + classifies an action that destroys the integrity of computer-based + information as unethical and unacceptable; and the Code of Ethics of + SAGE, USENIX, and LOPSA recognize the important of maintaining + integrity, reliability, and availability. + +7. Datagram Transmission + +7.1. Chemical Approach to the Atmospheric Link Layer + + Information is sent by transmitters producing a specialized form of + smoke, most often by emitting a specialized oil onto the exhaust + manifold. The oil, held in a pressurized container, is vaporized in + a thick white smoke, producing readable display. The makeup of the + smoke is often subject to patents, and any organization interested + should consult with their attorneys. Further details on transmission + + + +Ritter Experimental [Page 6] + +RFC 6217 Regional Broadcast 1 April 2011 + + + on the Physical Layer is beyond the scope of this RFC, but + implementers MAY refer to references for help. It is by design that + the broadcast mechanism does not result in incompatibilities if + implementers choose different Physical Layer implementations. + +7.2. Location + + The datagram MUST be displayed in the atmosphere, at an altitude of + 7000 to 17000 feet (2133 to 5181 meters). It SHOULD be written using + a "skytyping" method, similar to dot-matrix printing (Figure 4). + This method will provide better persistence of the datagram in the + presence of air currents. Additionally, it provides the ability for + parallelism by using additional avionic instruments. + + ####### ####### ####### ####### + # # # # + # # # # + # #### # #### + # # # # + # # # # + ####### ####### # # + + Figure 4: Skytyping Method in the Sky + + The most efficient method for broadcasting a datagram on this link + layer is the hire of specialized companies that perform this service + on a regular basis. For a large organization interested in using + this method frequently, it may be more cost-effective to develop + one's own methods. + +7.3. Physical Layer Conditions + + Transmission ability varies by atmospheric and regional conditions. + Adverse conditions, such as an accumulation of moisture or ice + crystals in the Physical Layer, may preclude transmission for a + period of time. During these periods, it is suggested broadcasts be + delayed, as higher-than-expected error rates may occur, and receivers + may not be prepared to process the transmission immediately. + + Additionally, solar radiation conditions affect transmission in a + predictable, cyclic manner. Depending on latitude, the medium may be + unusable for a lengthy period, during which alternate arrangements + must be made. + + Conditions may worsen before, during, or after a transmission, + resulting in higher-than-expected transmission error rates. Regional + operators should be familiar with their operating conditions and + + + + +Ritter Experimental [Page 7] + +RFC 6217 Regional Broadcast 1 April 2011 + + + consider the feasibility of implementing a casual or robust + infrastructure on this transmission medium. Some locales lend + themselves better to regular operation than others. + +8. References + +8.1. Normative References + + [1] Mogul, J., "Broadcasting Internet Datagrams", STD 5, RFC 919, + October 1984. + +8.2. Informative References + + [2] Kawamura, S. and M. Kawashima, "A Recommendation for IPv6 + Address Text Representation", RFC 5952, August 2010. + + [3] Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform + Resource Identifier (URI): Generic Syntax", STD 66, RFC 3986, + January 2005. + + [4] Cotton, M. and L. Vegoda, "Special Use IPv4 Addresses", BCP 153, + RFC 5735, January 2010. + + [5] Blanchet, M., "Special-Use IPv6 Addresses", RFC 5156, April + 2008. + + [6] Eastlake 3rd, D. and A. Panitz, "Reserved Top Level DNS Names", + BCP 32, RFC 2606, June 1999. + + [7] Hooke, A., "Interplanetary Internet", GSAW 2003, + <http://sunset.usc.edu/gsaw/gsaw2003/s3/hooke.pdf>. + + [8] Hinden, R. and S. Deering, "IP Version 6 Addressing + Architecture", RFC 4291, February 2006. + + [9] Waitzman, D., "Standard for the transmission of IP datagrams on + avian carriers", RFC 1149, April 1 1990. + + [10] Defense Advanced Research Projects Agency and Internet + Activities Board, "Ethics and the Internet", RFC 1087, January + 1989. + + + + + + + + + + +Ritter Experimental [Page 8] + +RFC 6217 Regional Broadcast 1 April 2011 + + +Author's Address + + Thomas Ritter + PO Box 541 + Hoboken, NJ 07030 + USA + + EMail: tom@ritter.vg + URI: http://ritter.vg + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +Ritter Experimental [Page 9] + |