A

The ASCII form of an internationalized domain name label, as used in the DNS. Every U-label has an equivalent A-label.

Plain language The ASCII form of an internationalized domain name, used in DNS lookups.

Used in RFC 3490 RFC 3491 RFC 5890 RFC 5894 RFC 6531 RFC 7484 RFC 8222 RFC 8399 RFC 8616 RFC 9598

A DNS resource record type from RFC 2874 that stores part of an IPv6 address plus a pointer to a prefix name. Chaining A6 records builds the full address.

Plain language A DNS record that stores part of an IPv6 address and points to another record for the remaining address parts.

Used in RFC 2874 RFC 3364

Authentication, Authorization and Accounting: checking who a user is, deciding what that user may do, and recording what was used.

Plain language Three steps for network access: checking identity, deciding permissions, and recording usage.

Used in RFC 2881 RFC 2903 RFC 2989 RFC 3127 RFC 3169 RFC 3374 RFC 3539 RFC 3726 RFC 3748 RFC 3957 RFC 4006 RFC 4187 RFC 4283 RFC 4721 RFC 4818 RFC 4962 RFC 5169 RFC 5176 RFC 5193 RFC 5580 RFC 5637 RFC 5713 RFC 5777 RFC 5778 and 18 more

A server that handles Authentication, Authorization and Accounting for network access. A home network may run several of them for redundancy.

Plain language A server that checks who you are, decides what you may do, and records what network resources you used.

Used in RFC 2903 RFC 2904 RFC 2989 RFC 3127 RFC 3846 RFC 6930 RFC 7268

A DNS resource record that maps a domain name to an IPv6 address.

Plain language A DNS record that connects a domain name to an IPv6 address.

Used in RFC 3364 RFC 3596 RFC 4472 RFC 4704 RFC 6334 RFC 6742 RFC 8005

ATM Adaptation Layer 5 is the ATM layer that carries variable-length packets over a virtual connection. It adds a trailer with a length and a CRC so errors are detected, but it does not correct them.

Used in RFC 1483 RFC 1755 RFC 2331 RFC 2364 RFC 2515 RFC 2684 RFC 2761 RFC 4454 RFC 4717

Augmented Backus-Naur Form, a compact notation used in RFCs to define exactly which strings are valid for a text format or protocol. Specified in RFC 5234.

Plain language A notation used in RFCs to precisely define which text strings are valid for a format or protocol.

Used in RFC 822 RFC 1137 RFC 1766 RFC 1869 RFC 1894 RFC 2122 RFC 2193 RFC 2234 RFC 2254 RFC 2255 RFC 2342 RFC 2389 RFC 2396 RFC 2445 RFC 2530 RFC 2569 RFC 2609 RFC 2614 RFC 2648 RFC 2653 RFC 2738 RFC 2812 RFC 2822 RFC 2846 and 243 more

A group of routers or a domain whose internal topology is opaque to the ingress router of an LSP. Treated as a single hop in path computation.

Used in RFC 3209 RFC 7897 RFC 7898

The logical definition of data, typically expressed in ASN.1 for OSI protocols. It describes the structure and meaning of the data independent of how it is transmitted.

Plain language The logical structure of data, independent of how it is transmitted or stored.

Used in RFC 941 RFC 1019 RFC 1698

A formal language for defining data structures and message formats in a machine-readable, platform-independent way.

Plain language A formal language for defining data structures and message formats in a machine-readable, platform-independent way.

Used in RFC 1022 RFC 1085 RFC 1158 RFC 1189 RFC 1274 RFC 1442 RFC 1448 RFC 1904 RFC 2222 RFC 3274 RFC 3447 RFC 4108 RFC 4134 RFC 4210 RFC 4531 RFC 4714 RFC 4910 RFC 4998 RFC 5408 RFC 6482 RFC 7193 RFC 10002 RFC 10003 RFC 10004

A message format for reporting abuse in the messaging infrastructure, designed so that reports can be generated and read automatically.

Plain language A structured format for reporting mail system abuse, designed so computers can automatically generate and read reports.

Used in RFC 6449 RFC 6650 RFC 6652 RFC 9991

One of four Wi-Fi priority classes for traffic: Voice, Video, Best-Effort and Background. Higher categories get quicker access to the radio channel.

Plain language One of four Wi-Fi priority classes (Voice, Video, Best-Effort, Background) that determines how quickly traffic gets radio channel time.

Used in RFC 7561 RFC 8325

The server-side device in PPPoE that answers a host's discovery request and terminates its PPP session. A host may be able to reach more than one.

Plain language The provider-side device in PPPoE that accepts a host's connection request and terminates its PPP session.

Used in RFC 2516 RFC 5007 RFC 6926

Mechanisms and policies that determine who is allowed to use a system or access specific data and resources, and who is not.

Plain language Rules that determine who may use a system or access specific resources.

Used in RFC 1107 RFC 1281 RFC 2830 RFC 3415 RFC 8341

One line of an access control list. It names a principal and a set of privileges that are either granted or denied to that principal.

Plain language One line of an access control list, naming a person or thing and what they may or may not do.

Used in RFC 3341 RFC 3744 RFC 8275 RFC 8519

A list of identity and rights pairs attached to an object. It decides which users may read, change or administer that object.

Plain language A list attached to a resource that specifies which users may read, change, or manage it.

Used in RFC 1281 RFC 1309 RFC 2244 RFC 2820 RFC 2829 RFC 3744 RFC 3860 RFC 4314 RFC 4768 RFC 5464 RFC 7204 RFC 7530 RFC 8006 RFC 8076 RFC 8519 RFC 8520 RFC 8783 RFC 9133 RFC 9631 RFC 9899 RFC 10065

The central device in a CAPWAP network that manages configuration, policy, and security for a group of wireless access points.

Plain language The central management device in a wireless network that directs multiple access points.

Used in RFC 5413 RFC 5414 RFC 5415 RFC 5416 RFC 5833 RFC 5834 RFC 7494

Network equipment, usually at a central office or street cabinet, that terminates subscribers' access lines. For DSL lines it is called a DSLAM.

Plain language Network equipment at a telephone office or street cabinet where subscriber lines converge.

Used in RFC 5713 RFC 5851 RFC 6320 RFC 7256

The Access Node Control Protocol (ANCP) carries Quality of Service, service-related and subscriber-related configuration and operations between a Network Access Server and an Access Node such as a DSLAM. The NAS sends requests to the Access Node, which authorises the actions and replies, and the Access Node in turn provides status reports.

Plain language The protocol a provider uses to tell the cabinet at the end of the street what quality of service to give each line.

Used in RFC 5713 RFC 5851

In 3GPP networks, a logical name that a mobile device connects to. It maps to a gateway and says what services and IP connectivity (IPv4, IPv6 or IPv4v6) the device may use.

Plain language In mobile networks, a logical name that a device connects to, which maps to a gateway and specifies available services.

Used in RFC 6342 RFC 6459

The router that directly serves a mobile node when connected to a network, providing IP connectivity and network services.

Plain language The router that directly serves a mobile device's IP connectivity and network services when connected.

Used in RFC 3374 RFC 4260 RFC 4957 RFC 5121 RFC 5268 RFC 5380 RFC 5568

In OAuth, a string issued by an authorization server that stands for permission granted to a client. The client presents it to a resource server instead of using the owner's password.

Plain language A string issued by an authorization server that grants permission without exposing the owner's password.

Used in RFC 2179 RFC 6749 RFC 6750 RFC 6819 RFC 7009 RFC 7521 RFC 7522 RFC 7523 RFC 7591 RFC 7628 RFC 7635 RFC 7636 RFC 7662 RFC 8252 RFC 8471 RFC 8495 RFC 8628 RFC 8693 RFC 8705 RFC 8707 RFC 8898 RFC 8959 RFC 9068 RFC 9200 and 22 more

In MPEG, the smallest piece of a stream that has its own timing information. An audio frame or a video picture is an example.

Plain language In MPEG, the smallest unit of a stream with its own timing, such as one audio frame or video picture.

Used in RFC 3640 RFC 3984 RFC 6190 RFC 9328 RFC 9584

A RADIUS reply that says the server needs more proof, such as a one-time code. The client prompts the user and sends a new Access-Request with the answer and the State attribute.

Plain language A RADIUS response saying the server needs more proof, such as a one-time code.

Used in RFC 2271 RFC 2865 RFC 5080 RFC 5090

ASCII Compatible Encoding label. An ASCII-only domain label that begins with a special prefix and whose remainder is the Punycode form of a Unicode string.

Plain language An ASCII-only domain label with a special prefix marking it as the encoded form of an internationalized name.

Used in RFC 3490 RFC 3491 RFC 3492 RFC 5890 RFC 5891 RFC 5893 RFC 5894 RFC 6055 RFC 9233 RFC 9549

A DCCP option that gives a run-length encoded history of which packets were received, received with an ECN mark, or not yet received. It lets a sender see exactly what was lost.

Plain language A DCCP option listing which packets were received, received with a congestion mark, or still missing.

Used in RFC 4340 RFC 4341

The Automated Certificate Management Environment, a protocol in which a client talks to a certificate authority's server to request and manage certificates automatically.

Plain language A protocol for automatically requesting and managing digital certificates without manual intervention.

Used in RFC 9444 RFC 9773

A test a certificate authority sets so that an applicant can prove control of a domain name, such as http-01 or dns-01.

Plain language A test that a certificate authority requires to verify you control a domain name.

Used in RFC 8555 RFC 8657 RFC 8737 RFC 8738 RFC 8739 RFC 9060 RFC 9444 RFC 9447 RFC 9448 RFC 9799 RFC 9891

A way of measuring a network by sending synthetic test traffic through it and observing what happens, rather than watching real user traffic.

Plain language Measuring network performance by sending test traffic and observing what happens to it.

Used in RFC 2330 RFC 6808 RFC 6985 RFC 7312 RFC 7497 RFC 7536 RFC 7820 RFC 8762 RFC 9097

Techniques used by network devices to manage queue sizes and signal congestion early, before buffers overflow.

Plain language Techniques routers use to manage queue size and signal congestion before buffers overflow.

Used in RFC 2309 RFC 2481 RFC 3168 RFC 3289 RFC 3819 RFC 4594 RFC 5127 RFC 5166 RFC 5562 RFC 6077 RFC 6297 RFC 7141 RFC 7567 RFC 8033 RFC 8034 RFC 8087 RFC 8257 RFC 8289 RFC 8290 RFC 8311 RFC 8622 RFC 8698 RFC 8867 RFC 8869 and 7 more

Authentic Data. A DNS header bit set by a name server in a response to say that it considers all RRsets in the Answer and Authority sections authentic. It is only meaningful over a trusted channel.

Plain language A DNS header flag indicating that a name server considers the response data authentic.

Used in RFC 2065 RFC 4035 RFC 6731 RFC 7646

The protocol layer that sits between the convergence layer and individual network paths, handling encapsulation or security for each path.

Plain language A protocol layer between the convergence layer and individual network paths, handling encapsulation for each.

Used in RFC 3441 RFC 9188

An audio compression algorithm that reduces the data rate of a 64 kilobit-per-second PCM audio stream to 32 kilobits per second by encoding the differences between successive samples and adapting the quantization step.

Plain language An audio compression algorithm that reduces data rate by encoding sample differences with adaptive quantization.

Used in RFC 1911 RFC 2422

Data that is covered by an authentication tag but is not encrypted and is not part of the output, such as a packet header that must stay readable.

Plain language Data that is authenticated but not encrypted, remaining readable while still protected from tampering.

Used in RFC 3610 RFC 4106 RFC 4543 RFC 7516 RFC 9058

Grouping addresses with common prefixes into a single routing entry so routers can forward many addresses with one rule.

Plain language Grouping addresses with common prefixes into one routing rule to simplify routing tables.

Used in RFC 1287 RFC 1366 RFC 1454 RFC 1518 RFC 1519 RFC 1887 RFC 2374 RFC 2909 RFC 4852 RFC 6115

In classful addressing, one of five predefined categories (A, B, C, D, E) that determined how many bits identified the network versus the local host. Class A provided the most host addresses, Class C the fewest.

Plain language In classful addressing, one of five predefined categories (A, B, C, D, E) determining network and host address bits.

Used in RFC 1335 RFC 1375

A kind of network address, such as IPv4 or IPv6. A system may support one family or several.

Plain language A type of network address system, such as IPv4 or IPv6.

Used in RFC 2858 RFC 4012 RFC 4038 RFC 4684 RFC 5838 RFC 6156 RFC 8305 RFC 8983

A numeric code used by BGP to identify the type of routing information being carried, such as IPv4 (1) or IPv6 (2).

Plain language A numeric code identifying the type of address being routed, such as IPv4 (1) or IPv6 (2).

Used in RFC 2858 RFC 4760 RFC 5549 RFC 8060

A SIP address that identifies a user, such as a SIP, SIPS or tel URI. A participant may have more than one.

Plain language A SIP address identifying a user, such as a SIP URI or telephone number.

Used in RFC 3680 RFC 3764 RFC 4474 RFC 4596 RFC 5627 RFC 7044 RFC 7315 RFC 7865 RFC 7890 RFC 7904 RFC 8224

An approach to the IPv4 address shortage in which several hosts use the same IPv4 address and are told apart by non-overlapping sets of transport-layer ports.

Plain language An approach to the IPv4 shortage where multiple hosts share one address but use different port ranges.

Used in RFC 6967 RFC 7618 RFC 9313

A table of prefixes, each with a precedence and a label, that an IPv6 host uses to choose among several source and destination addresses. RFC 6724 defines its default contents.

Plain language A table with address prefixes and priorities that helps a system choose among several addresses.

Used in RFC 5220 RFC 7078

The table in a BGP speaker that holds the routes learned from each neighbor before local policy is applied.

Used in RFC 1771 RFC 9069 RFC 9324

A relationship between two neighboring routers in an IS-IS network. An adjacency in the UP state means the neighbors are actively exchanging routing information.

Plain language An active relationship between two neighboring routers in an IS-IS network that exchange routing information.

Used in RFC 1246 RFC 1247 RFC 1583 RFC 1586 RFC 2178 RFC 2642 RFC 3036 RFC 3623 RFC 3719 RFC 3787 RFC 3847 RFC 4061 RFC 4062 RFC 4444 RFC 4812 RFC 5303 RFC 5796 RFC 5882 RFC 6320 RFC 7177 RFC 9454 RFC 10041

In X.400, a network administered by a public service provider or large organization, identified as part of an X.400 O/R name.

Plain language In X.400, a network administered by a service provider or large organization.

Used in RFC 987 RFC 1664 RFC 5585 RFC 7601

A network or set of networks operated and controlled by a single organization or authority.

Plain language A network or group of networks operated and controlled by a single organization.

Used in RFC 1125 RFC 1136 RFC 1272 RFC 1478 RFC 1479 RFC 3340 RFC 4375 RFC 6418 RFC 8190

A link attribute, also called a color, that is a bitmask used in traffic engineering. A set bit marks the link as belonging to the corresponding group.

Plain language A link attribute (or color) marking which traffic engineering groups may use or avoid a link.

Used in RFC 3970 RFC 4209 RFC 7308 RFC 9104 RFC 9917

An organization or operator that is responsible for a part of the Internet mail system, and so for the domain names it uses. Also called an ADMD.

Plain language An organization managing part of the Internet mail system and the domain names it uses.

Used in RFC 7208 RFC 8601

A boundary defined by network administrators that limits the reach of multicast traffic. Each scope has its own set of multicast addresses.

Plain language A boundary set by network administrators that limits multicast traffic to a specific area.

Used in RFC 2365 RFC 2730 RFC 2771 RFC 2776 RFC 2908

A check that decides whether a link has enough spare capacity to accept a new reservation, and refuses it if not.

Plain language A check deciding whether a link has enough capacity for a new reservation.

Used in RFC 1633 RFC 2188 RFC 2205 RFC 2208 RFC 2211 RFC 2212 RFC 2386 RFC 2688 RFC 2749 RFC 2750 RFC 2751 RFC 2814 RFC 2816 RFC 2990 RFC 2998 RFC 3175 RFC 3181 RFC 3313 RFC 4128 RFC 5127 RFC 5559 RFC 5670 RFC 5974 RFC 6016 and 6 more

Asymmetric Digital Subscriber Loop: a technology for carrying data over a telephone line, with a modem (ATU-C) at the central end and another (ATU-R) at the remote end.

Plain language A technology for sending data over a telephone line using modems at both ends.

Used in RFC 2662 RFC 4706

Authenticated Encryption with Associated Data. A cipher mode that encrypts data and checks that it has not been changed in one step. All ciphers in TLS 1.3 are AEAD ciphers.

Plain language An encryption method that scrambles data and proves it has not been changed in a single operation.

Used in RFC 3610 RFC 4106 RFC 4253 RFC 4309 RFC 5083 RFC 5084 RFC 5116 RFC 5282 RFC 5288 RFC 5289 RFC 5487 RFC 5647 RFC 5669 RFC 6054 RFC 6209 RFC 6367 RFC 6460 RFC 6655 RFC 7165 RFC 7251 RFC 7253 RFC 7366 RFC 7457 RFC 7516 and 65 more

Advanced Encryption Standard, a symmetric encryption algorithm that scrambles data using a secret key. The key can be 128, 192, or 256 bits long.

Plain language A symmetric encryption standard that scrambles data using a secret key (128, 192, or 256 bits).

Used in RFC 3394 RFC 3565 RFC 3566 RFC 3602 RFC 3664 RFC 3686 RFC 3766 RFC 3826 RFC 4106 RFC 4309 RFC 4543 RFC 4568 RFC 5008 RFC 5077 RFC 5274 RFC 5430 RFC 5796 RFC 5926 RFC 6030 RFC 6031 RFC 6033 RFC 6318 RFC 6379 RFC 6380 and 2 more

A way to use the AES block cipher as a stream cipher by encrypting successive counter values and XORing the result onto the data.

Plain language A way to use the AES cipher as a stream cipher by encrypting counter values and mixing the result with data.

Used in RFC 3268 RFC 3610 RFC 3686 RFC 3711 RFC 3723 RFC 3830 RFC 4106 RFC 4305 RFC 4309 RFC 4344 RFC 4543 RFC 4568 RFC 4656 RFC 4763 RFC 5083 RFC 5084 RFC 5116 RFC 5297 RFC 5529 RFC 5669 RFC 5930 RFC 6054 RFC 6188 RFC 6239 and 9 more

Advanced Encryption Standard in Galois/Counter Mode; an encryption and authentication algorithm that both encrypts data and proves it has not been tampered with.

Plain language An encryption and authentication algorithm that scrambles data and proves it has not been tampered with.

Used in RFC 4106 RFC 4543 RFC 4705 RFC 5084 RFC 5647 RFC 5959 RFC 7402 RFC 7714 RFC 8247 RFC 9206 RFC 10004

The Address Family Transition Router is the provider-side end of a Dual-Stack Lite IPv4-over-IPv6 tunnel. Customer equipment connects to it by name.

Plain language The provider-side endpoint of a Dual-Stack Lite IPv4-over-IPv6 tunnel.

Used in RFC 6334 RFC 6519 RFC 6674 RFC 6908 RFC 7393 RFC 7870

A message sent downstream when a server layer fault is detected. It lets the layers above suppress their own alarms.

Plain language A message sent downstream when a server layer detects a fault, suppressing duplicate alarms from upper layers.

Used in RFC 1595 RFC 3592 RFC 4842 RFC 5086 RFC 5087 RFC 6310 RFC 6371 RFC 6427

A helper on a NAT device that inspects and rewrites application payloads, such as FTP PORT commands, that carry IP addresses or ports inside the data.

Plain language A device on a NAT that inspects and rewrites application payloads carrying IP addresses or ports.

Used in RFC 2663 RFC 2993 RFC 3022 RFC 3234 RFC 3235 RFC 3424 RFC 4787 RFC 4924 RFC 4961 RFC 4966 RFC 5382 RFC 5597 RFC 6144 RFC 6269 RFC 6384 RFC 8725 RFC 8839 RFC 9864

The none value of the alg header, which makes an Unsecured JWT with no signature. Implementations must support it, but a verifier that accepts it when a signature was expected can be fooled by forged tokens.

Plain language A JWT header value indicating no signature, which is dangerous if signature verification is expected.

Used in RFC 7515 RFC 7518 RFC 7519 RFC 8725

The ability of a protocol to name the algorithm it uses, so that an algorithm can be replaced without redesigning the format.

Plain language The ability to name and swap the algorithm a protocol uses without redesigning the format.

Used in RFC 4108 RFC 5035 RFC 6862 RFC 7696 RFC 9231 RFC 9904

An attack in which the attacker changes the algorithm, or its parameters, used in a signed or authenticated message so that verification gives a different result.

Plain language An attack where the attacker changes the algorithm or its parameters to fool verification.

Used in RFC 6211 RFC 8725 RFC 8933

Application-Layer Protocol Negotiation, a TLS extension in which client and server agree on which protocol to speak inside the connection. HTTP/2 over TLS uses the identifier h2.

Plain language A TLS extension letting client and server agree which protocol to use inside the connection.

Used in RFC 7301 RFC 7443 RFC 7639 RFC 7838 RFC 8323 RFC 8404 RFC 8447 RFC 8701 RFC 8737 RFC 8738 RFC 8744 RFC 8833 RFC 8915 RFC 9000 RFC 9001 RFC 9103 RFC 9112 RFC 9113 RFC 9114 RFC 9209 RFC 9250 RFC 9289 RFC 9325 RFC 9368 and 11 more

The Alternative Services mechanism, through which a server tells a client in an Alt-Svc header field or an HTTP/2 ALTSVC frame that the same service is also reachable another way. HTTP/3 uses the token h3, as in Alt-Svc: h3=":443".

Plain language A mechanism letting a server tell a client that the same service is available through another route.

Used in RFC 7838 RFC 8030 RFC 8164 RFC 8336 RFC 9114 RFC 9369 RFC 9460 RFC 9848

A passive measurement method that marks consecutive batches of packets so that packet loss, latency and jitter can be measured on live traffic.

Plain language A measurement method marking consecutive packet batches to measure loss, delay, and jitter on real traffic.

Used in RFC 8889 RFC 9341 RFC 9342 RFC 9343 RFC 9779 RFC 9947

An SDP grouping semantic that lets a media stream offer multiple network addresses of different types (such as IPv4 and IPv6) as alternatives, with a preference order.

Plain language An SDP mechanism offering multiple network address types (IPv4 and IPv6) as alternatives with preferred order.

Used in RFC 4091 RFC 4092

Application-Layer Traffic Optimization; a protocol that helps applications choose which servers to use based on network topology and costs.

Plain language A protocol helping applications choose servers based on network topology and cost.

Used in RFC 5693 RFC 7752 RFC 7971 RFC 8189 RFC 8686 RFC 8895 RFC 8896 RFC 9240 RFC 9439

Authority that is attached to a request automatically instead of being named in it. Cookies are an example: the browser adds them to every matching request, which is why cross-site request forgery works.

Plain language Authority automatically included in a request without being explicitly named, like cookies in web browsers.

Used in RFC 6265 RFC 6454

An attack in which a server turns one incoming request into many outgoing ones, so a single cheap message can flood a victim with much more traffic.

Plain language An attack turning one request into many outgoing responses, flooding a victim with much more traffic.

Used in RFC 4453 RFC 5062 RFC 5358 RFC 5360 RFC 5363 RFC 7252 RFC 7835 RFC 9322 RFC 9853

Data in an MPLS packet that goes with a Network Action. It may be input to the action or the result of it, and it can sit in the label stack or after it.

Plain language Data in an MPLS packet accompanying a network action, either input to it or the result.

Used in RFC 2292 RFC 8331 RFC 9613 RFC 9791

A statistical test that checks whether several samples of measurements plausibly come from the same underlying distribution. RFC 6808 uses it to compare delay results from different tools.

Plain language A statistical test checking whether several measurement samples plausibly come from the same distribution.

Used in RFC 2330 RFC 6576 RFC 6808

A single bit in the OSPF TE link performance sub-TLVs that is set when a measured value exceeds a configured maximum threshold and cleared when the value falls back below the reuse threshold. RFC 7471 uses it to mark a sub-TLV that reports a link in an abnormal state rather than its steady state.

Plain language One bit that says the link is not behaving normally right now.

Used in RFC 7471 RFC 8570

The group of servers whose externally visible TLS behavior is the same, so that a connection to one cannot be told apart from a connection to another. In ECH, the set is the names served under the same client-facing server and configuration.

Plain language The group of servers with identical visible TLS behavior, so connections to them appear identical.

Used in RFC 3693 RFC 6462 RFC 6973 RFC 7619 RFC 7937 RFC 8280 RFC 8932 RFC 9230 RFC 9458 RFC 9576 RFC 9620 RFC 9848 RFC 9849

A way of offering files for public download over ftp, where visitors log in without an account of their own, so that anyone can fetch the files.

Plain language A way to publicly share files over FTP where visitors log in without their own account.

Used in RFC 1175 RFC 1402 RFC 1470 RFC 1689

An unpredictable value sent by a server that the other side must send back. It shows the sender is an active participant and not part of a flooding attack.

Plain language A value sent by a server that must be returned to prove the sender is active, not part of a flooding attack.

Used in RFC 2408 RFC 2412 RFC 3104 RFC 5931

The classic multicast mode in which a receiver joins a group address G and receives traffic sent to that group by any source.

Plain language The classic multicast mode where a receiver joins a group and receives traffic from any sender.

Used in RFC 3738 RFC 3956 RFC 4604 RFC 5186 RFC 5374 RFC 5740 RFC 5757 RFC 6308 RFC 6450 RFC 8815

An address shared by a set of interfaces, usually on different nodes. A packet sent to it is delivered to the nearest one, as measured by routing.

Plain language An address shared by multiple interfaces, usually on different nodes, with packets delivered to the nearest one.

Used in RFC 1546 RFC 1621 RFC 1884 RFC 1888 RFC 2101 RFC 2373 RFC 2460 RFC 2501 RFC 2526 RFC 2775 RFC 2780 RFC 3068 RFC 3258 RFC 3446 RFC 3484 RFC 3513 RFC 3568 RFC 3618 RFC 3627 RFC 3775 RFC 3879 RFC 3956 RFC 3964 RFC 4007 and 86 more

A message relaying service for application programs, specified as a BEEP profile. Applications attach to a relaying mesh as named endpoints and send data elements naming an originator and one or more recipients.

Plain language A service that lets programs pass messages to each other through a network of forwarding servers.

Used in RFC 3340 RFC 3341

An optional POP3 login command. The client sends an MD5 digest of the server's one-time timestamp plus a shared secret instead of the password itself.

Plain language An optional POP3 login method where the client sends an MD5 digest rather than the password itself.

Used in RFC 1460 RFC 1725 RFC 1939 RFC 1957 RFC 2195 RFC 2384 RFC 2449 RFC 3206 RFC 6856

A protocol suite with an open peer-to-peer architecture that runs over a variety of transmission media. It can interoperate with the IP protocol suite through encapsulation.

Plain language A peer-to-peer protocol suite that allows computers and printers to communicate over various media.

Used in RFC 1378 RFC 1742

A piece of data that can be processed out of order with respect to other pieces. It is the smallest unit of error recovery in an ALF design.

Plain language A piece of data that can be processed independently and is the smallest recovery unit in an ALF design.

Used in RFC 2736 RFC 2887 RFC 3119 RFC 6363 RFC 6865

An intermediary that relays a particular application protocol, such as e-mail or FTP, between a private network and the outside, so that private hosts get the service without having IP connectivity to outside hosts.

Plain language An intermediary relaying a specific application protocol between private and outside networks.

Used in RFC 1415 RFC 1530 RFC 1918 RFC 2101 RFC 2588 RFC 2775 RFC 2871 RFC 3027 RFC 3102 RFC 3103 RFC 3303 RFC 3665 RFC 3715 RFC 4028 RFC 4838 RFC 6875 RFC 7092 RFC 9944

A functional entity that hosts one or more communication application instances. It terminates SIP signaling from user agents and controls media servers to deliver services such as IVR or conferencing.

Plain language A system hosting communication applications that terminates user agent signaling and controls media delivery.

Used in RFC 3332 RFC 5567 RFC 6231 RFC 7245

A single process instance of an Application Server, for example a primary or backup controller. An Application Server is modeled at the gateway as an ordered list of these processes.

Plain language A single process instance of an application server, part of an ordered list serving a shared job.

Used in RFC 3057 RFC 4233

The string that starts a DDDS lookup. Its lexical structure must imply a single delegation path that the rewrite rules can be applied to.

Plain language The string a DDDS lookup starts from.

Used in RFC 3402 RFC 3761 RFC 5464 RFC 6116 RFC 8917

Describes a sender that sends less than the congestion or receiver window allows because the application has no more data ready. The RFC calls such senders rate-limited.

Plain language Describes a sender sending less than the network allows because the application has no more data ready.

Used in RFC 2861 RFC 7661

The media type for a single DNS message in the RFC 1035 on-the-wire format, up to 65535 bytes, used as the body of DoH requests and responses.

Plain language The media type for a single DNS message in the RFC 1035 on-the-wire format, up to 65535 bytes.

Used in RFC 883 RFC 2540 RFC 2671 RFC 2931 RFC 3226 RFC 3597 RFC 3755 RFC 4343 RFC 5936 RFC 6762 RFC 6895 RFC 7766 RFC 8467 RFC 8484 RFC 8618 RFC 8764 RFC 9267 RFC 9619 RFC 9953

An evolution of SNA that allows dynamic routing and peer-to-peer communication without a central hub, bringing more flexibility to SNA networks.

Plain language An evolution of SNA allowing dynamic routing and peer-to-peer communication without a central hub.

Used in RFC 1593 RFC 2353

In TRILL, the switch on a multi-access link that handles native frames for a given VLAN. It is chosen so that at most one switch does this per VLAN.

Plain language In TRILL, the switch on a multi-access link handling native frames for a specific VLAN.

Used in RFC 6439 RFC 8139

A humorous RFC published on 1 April, a long-running tradition in the series. RFC 2324 and RFC 2325 are examples. They are written in the formal style of real specifications.

Plain language A humorous RFC published on April 1st, written in the formal style of real specifications.

Used in RFC 748 RFC 1097 RFC 1217 RFC 1924 RFC 1925 RFC 1926 RFC 2100 RFC 2134 RFC 2321 RFC 2322 RFC 2324 RFC 2549 RFC 2550 RFC 2551 RFC 2795 RFC 3093 RFC 3251 RFC 3252 RFC 3751 RFC 4041 RFC 4042 RFC 4824 RFC 5241 RFC 5242 and 16 more

A system for locating files at anonymous FTP archive sites on the Internet. Archie maintains an indexed database of files from over 1,000 FTP sites worldwide, allowing users to search for specific files by name or pattern.

Used in RFC 1402 RFC 1739

An OSPF router attached to more than one area, which summarizes routing information between them.

Plain language An OSPF router connected to multiple areas that summarizes routing information between them.

Used in RFC 1131 RFC 1247 RFC 1253 RFC 1583 RFC 1584 RFC 1793 RFC 2178 RFC 2328 RFC 2370 RFC 2740 RFC 3101 RFC 3509 RFC 4098 RFC 4105 RFC 4561 RFC 4577 RFC 4674 RFC 4920 RFC 5088 RFC 5130 RFC 5152 RFC 5185 RFC 5250 RFC 5283 and 30 more

An IETF leader who oversees the working groups in one technical area and sits on the IESG. Area Directors are selected by the NomCom.

Plain language An IETF leader overseeing working groups in one technical area and serving on the IESG.

Used in RFC 3131 RFC 3683 RFC 3710 RFC 3774 RFC 4052 RFC 4858 RFC 4929 RFC 6701 RFC 9281

The elected representative router within a Level 1 area that generates and originates the proxy LSP on behalf of the entire area.

Plain language The elected router in a Level 1 area that generates and originates the proxy LSP for the entire area.

Used in RFC 9666 RFC 9667

The Address Resolution Protocol. A host uses it to find the hardware address that goes with an IP address on the same network. RARP is its inverse.

Plain language The Address Resolution Protocol, used to find the hardware address matching an IP address on the same network.

Used in RFC 824 RFC 826 RFC 828 RFC 831 RFC 891 RFC 893 RFC 894 RFC 903 RFC 906 RFC 917 RFC 919 RFC 922 RFC 925 RFC 948 RFC 961 RFC 985 RFC 990 RFC 1009 RFC 1027 RFC 1029 RFC 1042 RFC 1044 RFC 1051 RFC 1060 and 104 more

The table in which a host stores the protocol-address to hardware-address pairings it has learned, so it does not have to broadcast a request for every packet.

Plain language A table storing protocol-to-hardware address mappings so repeated lookups are unnecessary.

Used in RFC 826 RFC 925 RFC 1027 RFC 1044 RFC 1329 RFC 1868 RFC 2176 RFC 2320 RFC 2390 RFC 2834 RFC 2835 RFC 4436 RFC 5227 RFC 8302 RFC 8344

An attack in which a host sends forged ARP replies so that others store the wrong hardware address for an IP address, which can redirect traffic through the attacker. ARP has no authentication, so networks add protections such as Dynamic ARP Inspection.

Plain language An attack using forged ARP replies to make others store wrong hardware addresses for IP addresses.

Used in RFC 826 RFC 2225 RFC 2390 RFC 2834 RFC 4036 RFC 4436 RFC 4732 RFC 6747 RFC 6941 RFC 6959 RFC 7039 RFC 7384 RFC 7454 RFC 7513 RFC 8171 RFC 8302 RFC 9047 RFC 9161

The Advanced Research Projects Agency Network, the predecessor to the modern Internet, operational from 1969 to 1989.

Plain language The Advanced Research Projects Agency Network, the predecessor to the modern Internet (1969-1989).

Used in RFC 7 RFC 63 RFC 78 RFC 107 RFC 151 RFC 281 RFC 283 RFC 306 RFC 333 RFC 342 RFC 344 RFC 353 RFC 362 RFC 366 RFC 439 RFC 441 RFC 443 RFC 604 RFC 608 RFC 846 RFC 851 RFC 878 RFC 952 RFC 1000 and 3 more

The BGP path attribute listing the autonomous systems a route has traversed, as AS_SEQUENCE and AS_SET segments. A speaker adds its own AS number when it advertises a route to an external peer, and a router rejects a route whose AS_PATH already contains its own AS.

Plain language The BGP attribute listing the autonomous systems a route has passed through.

Used in RFC 1105 RFC 1164 RFC 1265 RFC 1267 RFC 1364 RFC 1403 RFC 1771 RFC 1772 RFC 1774 RFC 1965 RFC 1997 RFC 2280 RFC 2439 RFC 2622 RFC 3065 RFC 3345 RFC 4098 RFC 4271 RFC 4272 RFC 4760 RFC 4786 RFC 4893 RFC 5065 RFC 5575 and 25 more

A loosely coordinated project that runs servers to answer reverse DNS queries for private-use IPv4 addresses. It keeps those junk queries away from the rest of the reverse DNS.

Plain language A project running servers to answer reverse DNS queries for private IP addresses, keeping junk queries separate.

Used in RFC 6305 RFC 7534 RFC 7535

OpenPGP's printable encoding of binary data, made of base64 text plus a 24-bit CRC checksum, so that it survives channels that only carry text.

Plain language OpenPGP's base64 encoding of binary data with a checksum, allowing it to travel through text-only channels.

Used in RFC 1288 RFC 2015 RFC 2440 RFC 3156 RFC 4880 RFC 9580

Abstract Syntax Notation One, a language for describing the structure of data independently of how it is written as bytes. Encoding rules such as BER and DER turn ASN.1 values into octets.

Plain language Abstract Syntax Notation One, a language describing data structure independently of how it is stored as bytes.

Used in RFC 1014 RFC 1021 RFC 1022 RFC 1023 RFC 1024 RFC 1052 RFC 1065 RFC 1066 RFC 1076 RFC 1155 RFC 1156 RFC 1157 RFC 1189 RFC 1208 RFC 1212 RFC 1213 RFC 1214 RFC 1227 RFC 1229 RFC 1230 RFC 1231 RFC 1232 RFC 1233 RFC 1238 and 320 more

A package of identity and security information, signed or otherwise integrity protected by its issuer, that can be shared across security domains. It typically names a subject, an issuer and the conditions under which it is valid.

Used in RFC 7521 RFC 7523 RFC 7861

A side channel that runs inside a pseudowire alongside the user data. It carries control and management messages, marked by a header whose first nibble is 0001b.

Plain language A side channel running inside a pseudowire alongside user data, carrying control and management messages.

Used in RFC 5317 RFC 6426 RFC 6478

Data given to an AEAD algorithm that is authenticated but not encrypted, such as addresses or sequence numbers. It stays readable but cannot be altered without detection.

Used in RFC 5116 RFC 7253

SCTP's name for a connection between two endpoints. Unlike a TCP connection, it can span several IP addresses on each side and carry many streams.

Plain language SCTP's term for a connection between two endpoints that can span multiple IP addresses and carry many streams.

Used in RFC 700 RFC 1305 RFC 2788 RFC 2960 RFC 3057 RFC 3257 RFC 3868 RFC 3873 RFC 4165 RFC 4895 RFC 4960 RFC 5043 RFC 5061 RFC 5062 RFC 5203 RFC 5907 RFC 6458 RFC 6525 RFC 6526 RFC 6780 RFC 7551 RFC 8261 RFC 8303 RFC 8537 and 9 more

A set of subservices linked by dependencies that together represent what a service relies on. Agents report a health status and symptoms for each node in it.

Plain language A set of subservices linked by dependencies representing what a service relies on, with health status tracking.

Used in RFC 9417 RFC 9418

A CMS content type that holds public and private keys used in asymmetric cryptography, along with metadata and attributes describing those keys.

Used in RFC 5959 RFC 7906 RFC 9881

A switched network technology that transmits data in fixed-size cells and supports dynamic connection establishment with quality-of-service guarantees.

Plain language A switched network technology transmitting data in fixed-size cells with dynamic connection setup and quality guarantees.

Used in RFC 1483 RFC 1755 RFC 1932 RFC 1937 RFC 2022 RFC 2105 RFC 2225 RFC 2297 RFC 2331 RFC 2332 RFC 2380 RFC 2381 RFC 2382 RFC 2383 RFC 2417 RFC 2443 RFC 2502 RFC 2515 RFC 2520 RFC 2684 RFC 2685 RFC 2761 RFC 3033 RFC 3035 and 9 more

The fixed-size unit of an ATM network. The interfaces table counts cells rather than bytes, and multiplies the cell count by 53 to get an octet count.

Plain language The small fixed-size packet that ATM networks carry. Each one is 53 bytes.

Used in RFC 2515 RFC 2761 RFC 4454 RFC 4717

The ARP protocol extended to work over ATM, where a server maps IP addresses to ATM addresses. Its companion InATMARP asks the other end of a connection for its addresses.

Plain language The ARP protocol extended to work over ATM, mapping IP addresses to ATM addresses.

Used in RFC 1577 RFC 1755 RFC 2170 RFC 2225

An XML document in the Atom Syndication Format that lists related items, called Entries. New and updated Entries come first, so clients can fetch just what changed.

Plain language An XML document listing related items (Entries) with newest ones first for efficient client updates.

Used in RFC 5023 RFC 8322

An operation that reads, changes and writes a value as one indivisible step, so no other access can slip in between. Examples are fetch-and-add and compare-and-swap.

Plain language An operation that reads, changes, and writes a value as one indivisible step with no interruption.

Used in RFC 7306 RFC 8508

The Layer 2 link that connects a customer edge device to a provider edge device in a Layer 2 VPN.

Plain language The Layer 2 link connecting a customer's edge device to the provider's edge device in a Layer 2 VPN.

Used in RFC 3916 RFC 3985 RFC 4448 RFC 4553 RFC 4664 RFC 5085 RFC 5641 RFC 5921 RFC 6073 RFC 6074 RFC 6310 RFC 6575 RFC 6624 RFC 6870 RFC 7023 RFC 7152 RFC 7275 RFC 7338 RFC 7387 RFC 8184 RFC 9744 RFC 9833 RFC 9834 RFC 9835 and 1 more

A digitally signed structure that binds authorization information such as group membership, role, or clearance to an identity, without including a public key.

Plain language A digitally signed structure binding authorization information (group, role, clearance) to an identity without a public key.

Used in RFC 2904 RFC 3114 RFC 3281 RFC 5755 RFC 5878 RFC 8550

A client choice in IPP between printing a job exactly as requested or rejecting it, and letting the printer ignore or substitute unsupported settings so the job still prints.

Plain language A printer configuration choice: execute a job exactly as requested or skip unsupported settings.

Used in RFC 2911 RFC 8011

The name and type of a field in an LDAP entry, such as 'givenName', 'mail', or 'description'.

Plain language The name and data type of a field in an LDAP entry, such as 'name' or 'email'.

Used in RFC 1274 RFC 1430 RFC 2256 RFC 2596 RFC 2798 RFC 3703 RFC 4514 RFC 4519 RFC 5755 RFC 6929 RFC 7612

A unit of data in Diameter made of a code that names the attribute and a value. Messages are built from a list of them.

Plain language A data unit in Diameter containing a code and a value.

Used in RFC 2866 RFC 2924 RFC 3169 RFC 3216 RFC 3931 RFC 3955 RFC 4740 RFC 5191 RFC 5281 RFC 5447 RFC 5777 RFC 5779 RFC 5866 RFC 5872 RFC 6733 RFC 7156 RFC 7683 RFC 8583

The basic unit of data in a Diameter message: a code, a type and a value. A grouped AVP contains other AVPs inside it.

Plain language The basic unit of Diameter data: a code, type, and value.

Used in RFC 2661 RFC 3308 RFC 3573 RFC 3588 RFC 4072 RFC 4349 RFC 4454 RFC 4623 RFC 5447 RFC 5641 RFC 5777 RFC 5778 RFC 5779 RFC 6734 RFC 6735 RFC 7155 RFC 7423 RFC 7683 RFC 7886 RFC 7944 RFC 7966 RFC 8506 RFC 9390

A password-authenticated key exchange protocol where the server stores a verifier (a derived value like g^password mod p) rather than the password itself, providing security even if the verifier is compromised.

Plain language A password-authenticated key exchange where the server stores a derived verifier instead of the password itself.

Used in RFC 6628 RFC 8121 RFC 8125 RFC 9383 RFC 9807

A signed proof that a name or record type does not exist, built in DNSSEC from NSEC records. It stops attackers from forging negative answers.

Plain language A signed proof that a name or record type does not exist, built in DNSSEC from NSEC records.

Used in RFC 2065 RFC 2535 RFC 3833 RFC 4035 RFC 4470 RFC 5155 RFC 6605 RFC 6840 RFC 8976 RFC 9276 RFC 9824

An encryption algorithm that provides both confidentiality and authentication of the encrypted data, verifying that it has not been modified.

Plain language Encryption that both hides data and proves it has not been modified.

Used in RFC 5084 RFC 7253 RFC 7321 RFC 7366 RFC 7516 RFC 7905 RFC 8152 RFC 9058

A domain name that a DNS client uses to authenticate a DNS resolver, by comparing it with the name in the resolver's certificate.

Plain language A domain name a DNS client uses to verify a resolver's identity by comparing it with the resolver's certificate.

Used in RFC 8310 RFC 9463

An IP extension header that carries a cryptographic signature (Authentication Data) computed over the datagram to prove its origin and detect modifications.

Plain language An IP extension header carrying a cryptographic signature proving packet origin and detecting tampering.

Used in RFC 1810 RFC 1825 RFC 1826 RFC 2207 RFC 2401 RFC 2890 RFC 3566 RFC 4302 RFC 4543 RFC 5570 RFC 6071

A named way of proving identity to an SSH server, such as publickey, password or hostbased. The server lists which methods may continue, and the client chooses.

Plain language A named way of proving identity to an SSH server, such as public key or password.

Used in RFC 471 RFC 501 RFC 1022 RFC 1124 RFC 1225 RFC 1244 RFC 1246 RFC 1281 RFC 1334 RFC 1339 RFC 1411 RFC 1412 RFC 1445 RFC 1446 RFC 1492 RFC 1508 RFC 1509 RFC 1511 RFC 1616 RFC 1635 RFC 1636 RFC 1731 RFC 1734 RFC 1751 and 116 more

In HTTP authentication, a token such as Basic, Digest or Bearer that names the method used to produce credentials. A challenge and the matching Authorization header both begin with the scheme name.

Plain language In HTTP authentication, a token (like Basic or Bearer) naming the method producing credentials.

Used in RFC 912 RFC 1447 RFC 1813 RFC 1852 RFC 2203 RFC 2245 RFC 2264 RFC 2425 RFC 2520 RFC 2617 RFC 2839 RFC 3206 RFC 3325 RFC 3567 RFC 3651 RFC 4169 RFC 4189 RFC 4190 RFC 4284 RFC 4742 RFC 5310 RFC 6094 RFC 7235 RFC 7236 and 22 more

A short value appended to a ciphertext that lets the receiver check that the data and associated data were not altered. If the tag does not match, the message is rejected.

Plain language A short value appended to encrypted data letting the receiver check it has not been altered.

Used in RFC 3566 RFC 5084 RFC 5776 RFC 6562 RFC 6655 RFC 6904 RFC 7253 RFC 7714

An email header field (RFC 8601) that records the results of one or more message authentication checks, allowing downstream systems to know what authentication methods were used and what they found.

Used in RFC 7001 RFC 8904

A small record containing the client's name and a current timestamp, encrypted with the session key from a ticket. It proves the sender holds the key and that the request is fresh.

Plain language A small record with the client name and current timestamp, encrypted with the session key.

Used in RFC 1305 RFC 1334 RFC 1510 RFC 1994 RFC 2107 RFC 2264 RFC 2284 RFC 2403 RFC 2404 RFC 2620 RFC 2759 RFC 2866 RFC 2869 RFC 2942 RFC 3059 RFC 3543 RFC 3580 RFC 3748 RFC 4017 RFC 4072 RFC 4120 RFC 4121 RFC 4137 RFC 4187 and 26 more

A DNS name server that holds the real data for a zone, as opposed to one repeating what it has cached.

Plain language A DNS name server holding the real data for a zone, not cached data from another source.

Used in RFC 882 RFC 883 RFC 1033 RFC 1536 RFC 1996 RFC 2181 RFC 2182 RFC 2308 RFC 2870 RFC 3258 RFC 3655 RFC 4035 RFC 4074 RFC 4470 RFC 4892 RFC 5358 RFC 5452 RFC 5936 RFC 6147 RFC 6303 RFC 6563 RFC 6761 RFC 7534 RFC 7706 and 25 more

The optional part of a URI that follows the two slashes after the scheme. It has the form [userinfo@]host[:port] and names the server or registry that governs the rest of the URI.

Plain language The optional part of a URI following the scheme, with form [userinfo@]host[:port].

Used in RFC 1808 RFC 2396 RFC 2732 RFC 3981 RFC 3986 RFC 4088 RFC 4151 RFC 5122 RFC 5538 RFC 6270 RFC 6920 RFC 8089 RFC 8820

The process of determining what a user, service, or device is allowed to do, based on identity, role, group membership, time, or other attributes.

Plain language Determining what a user, service, or device is allowed to do based on identity, role, or other attributes.

Used in RFC 2138 RFC 2693 RFC 2704 RFC 2903 RFC 2905 RFC 2906 RFC 3891 RFC 4745 RFC 5176 RFC 7397

A short-lived credential that the authorization server gives the client after the owner approves. The client exchanges it for an access token at the token endpoint, so the token itself never passes through the user's browser.

Plain language A short-lived credential letting a client exchange it for an access token without exposing the user's password.

Used in RFC 2904 RFC 3867 RFC 5733 RFC 6749 RFC 6819 RFC 7636 RFC 8252 RFC 8707 RFC 9126 RFC 9207 RFC 9560 RFC 9700 RFC 10006 RFC 10017

The identity a client asks to act as after it has authenticated. It may differ from the authentication identity tied to its credentials.

Plain language The identity a client asks to act as after authenticating, which may differ from the authenticated identity.

Used in RFC 2222 RFC 3829 RFC 4422 RFC 4532

A secret value, such as a password, attached to an EPP object that a client must present to prove it may query or transfer that object.

Plain language A secret value (like a password) an EPP client must present to prove it may query or transfer an object.

Used in RFC 5733 RFC 9154

In OAuth, the server that authenticates the resource owner, obtains their approval, and issues access tokens to the client.

Plain language In OAuth, the server that authenticates the resource owner, obtains approval, and issues access tokens.

Used in RFC 2903 RFC 4284 RFC 6749 RFC 6750 RFC 6819 RFC 7009 RFC 7521 RFC 7522 RFC 7523 RFC 7591 RFC 7635 RFC 7636 RFC 7662 RFC 8053 RFC 8252 RFC 8414 RFC 8628 RFC 8693 RFC 8705 RFC 8707 RFC 8898 RFC 9068 RFC 9101 RFC 9126 and 19 more

The authz-info resource is the endpoint on a resource server where a client uploads an access token before it starts a DTLS session. The resource server keeps the token there and uses it to decide which requests the client is allowed to make.

Plain language The place on a server where the client deposits its access token before the secure connection starts.

Used in RFC 9200 RFC 9202

A link procedure in which the two ends of an Ethernet connection exchange their capabilities and settle on a common operating mode. In this MIB it can be enabled, disabled or restarted through SNMP.

Used in RFC 3636 RFC 4836

The ability of a network node to automatically determine and assign its own configuration parameters without manual intervention, using mechanisms like DHCP, SLAAC, or self-generation of addresses.

Plain language The ability of a network node to automatically determine its own configuration parameters without manual setup.

Used in RFC 1526 RFC 4057 RFC 5375 RFC 5505 RFC 5558

Autokey is the key exchange protocol defined in RFC 5906 for NTP version 4. It uses an NTP extension field, and the packet carrying that field is always followed by a Message Authentication Code.

Plain language The NTPv4 key exchange method, which adds an extra field and always signs the packet.

Used in RFC 5906 RFC 7822

AMT, defined in RFC 7450, carries multicast traffic over a unicast tunnel between a relay and a gateway so that it can cross network segments that cannot forward multicast.

Plain language A method carrying multicast traffic over a unicast tunnel so it can cross network segments that cannot forward multicast.

Used in RFC 8313 RFC 8777 RFC 9706

A reliability method in which the receiver reports what it got and the sender resends whatever is missing. A retransmission timer protects the process when feedback is lost.

Plain language A reliability method where the receiver reports what arrived and the sender resends what is missing.

Used in RFC 3819 RFC 8931

An ITU-T architecture for optical networks that supports dynamic provisioning of optical circuits through standardized signaling between network elements from multiple vendors.

Used in RFC 3474 RFC 6827

A secure, self-managing control plane that provides a protected channel for communication between autonomic nodes. It is established through a bootstrap process and serves as the foundation for ASA communication.

Plain language A secure, self-managing control plane providing a protected channel for autonomic nodes to communicate.

Used in RFC 7576 RFC 8368 RFC 8991 RFC 8994 RFC 9222 RFC 9315

Software running on an autonomic node that implements a specific autonomic function, either independently or as part of a distributed function.

Plain language Software on a node that implements a specific autonomic function independently or as part of a distributed function.

Used in RFC 7575 RFC 7576 RFC 8316 RFC 8990 RFC 8991 RFC 8993 RFC 9222

A routing domain under one administration, identified by an AS number, that exchanges routes with other such domains using BGP.

Plain language A routing domain under one administration identified by an AS number, exchanging routes with other domains using BGP.

Used in RFC 820 RFC 827 RFC 888 RFC 890 RFC 904 RFC 911 RFC 923 RFC 975 RFC 985 RFC 990 RFC 1009 RFC 1020 RFC 1058 RFC 1059 RFC 1062 RFC 1069 RFC 1092 RFC 1093 RFC 1104 RFC 1105 RFC 1117 RFC 1118 RFC 1125 RFC 1126 and 343 more

A router at the boundary of an autonomous system that peers with routers in other autonomous systems using EBGP.

Plain language A router at the boundary of an autonomous system that peers with other autonomous systems using EBGP.

Used in RFC 1403 RFC 1745 RFC 3101 RFC 4216 RFC 6198 RFC 9346

The RFC's term for a bird used as the physical medium for carrying IP datagrams. In RFC 1149 the datagram is a paper scroll wrapped around one of its legs.

Plain language An RFC term for a bird used as the physical medium for carrying IP datagrams.

Used in RFC 1149 RFC 2549 RFC 6214 RFC 7511