Glossary
V
39 terms.
- VALARM
The iCalendar component for a reminder, nested in a VEVENT or VTODO. It has an ACTION (AUDIO, DISPLAY or EMAIL) and a TRIGGER.
Like I'm five The little alarm clipped onto a plan.
- Validating resolver
A security-aware resolver that checks DNSSEC signatures itself rather than trusting an upstream server to do it.
Like I'm five A checker who inspects every seal personally.
Used in RFC 2535 RFC 3008 RFC 3833 RFC 4033 RFC 4035 RFC 4955 RFC 4956 RFC 5074 RFC 6147 RFC 6672 RFC 6840 RFC 6975 RFC 7583 RFC 7646 RFC 7901 RFC 8027 RFC 8145 RFC 8198 RFC 8499 RFC 8657 RFC 8749 RFC 8806 RFC 8901 RFC 8914 and 5 more
- Variable binding
In SNMP, a pairing of a variable's name (an OBJECT IDENTIFIER) with its value, or with an exception that explains why no value was returned.
Like I'm five A label stuck to a value, like a name tag on a box.
- Variant label
A label computed from an original label by substituting code points with their defined variants. Registry policy can block it or reserve it for the same owner as the original.
Like I'm five A look-alike spelling of a name made by swapping in letters that count as the same.
- vCard
A standardized text format for electronic business cards and contact information, defined in RFC 6350.
Like I'm five A digital version of a business card with your name, email, phone, and address.
Used in RFC 2426 RFC 2739 RFC 4770 RFC 6351 RFC 6352 RFC 6474 RFC 6493 RFC 6869 RFC 7095 RFC 8605 RFC 9553 RFC 9554 RFC 9555
- Vector Graphics
Display using lines, points, and shapes, where positions are specified by coordinates rather than as a grid of pixels. The alternative is raster graphics.
Like I'm five A picture made of lines drawn between points, like a pen drawing.
- Vendor-Specific Attribute
A RADIUS attribute (number 26) that lets a vendor define its own data, identified by the vendor's Private Enterprise Code. The vendor assigns the attribute types inside it.
Like I'm five A blank slot that each company may fill with its own special information.
- Vendor-Specific Extension (VSE)
An extensible mechanism in Mobile IPv4 that allows vendors to add custom fields to registration messages without modifying the core protocol.
Like I'm five A way for companies to add their own custom settings to the registration message without breaking the standard.
- Verifiable Data Structure
An append-only data structure, that can produce signed proofs about its contents, for example that an entry was included. Transparency services use one to record signed statements.
Like I'm five A diary that only lets you add pages, and can prove a page is in it.
- Version negotiation
The process by which two endpoints agree on which version of a protocol to use. It succeeds when they find a version both support.
Like I'm five Two people finding a language they both speak.
- VEVENT
The iCalendar component for a scheduled amount of time, such as a meeting or an all-day event. It needs a UID and DTSTAMP.
Like I'm five The small card for one planned thing.
Used in RFC 2445 RFC 2446 RFC 5545 RFC 7265 RFC 7529 RFC 7986 RFC 9073 RFC 9074
- Virtual circuit
A connection-oriented network service in which the network sets up and remembers a path for a conversation. RFC 1958 says datagrams are better than classical virtual circuits because they avoid state inside the network.
Like I'm five A phone line that the post office reserves for you and has to remember.
Used in RFC 466 RFC 852 RFC 874 RFC 877 RFC 878 RFC 883 RFC 955 RFC 1090 RFC 1294 RFC 1356 RFC 1382 RFC 1483 RFC 1490 RFC 1577 RFC 1581 RFC 1582 RFC 1586 RFC 1596 RFC 1598 RFC 1604 RFC 1613 RFC 1680 RFC 1755 RFC 1772 and 83 more
- Virtual Circuit Connectivity Verification
A protocol for testing the health and connectivity of pseudowire circuits, using different control channel types such as the Control Word, Router Alert Label, or TTL expiration.
Like I'm five A way to check if a pseudowire connection is working properly.
- Virtual concatenation
A method that bonds several TDM signals into one larger logical connection by striping data bytes across them. The member signals can travel separately.
Like I'm five Using several small pipes together so they work like one big pipe.
- Virtual File
A standard representation of file data independent of local system formats, identified by dataset name, date, time, originator and destination.
Like I'm five A file that is the same no matter what computer system receives it, like a standard letter format.
- Virtual Gateway
A collection of policy gateways from two adjacent domains that serves as the only inter-domain connection point recognized by IDPR, providing redundancy and load sharing.
Like I'm five A cluster of routers connecting two networks, which IDPR treats as a single connection point.
- Virtual hosting
Running many separate sites or services, each with its own name, from a single server or network address.
Like I'm five One house with many mailboxes, each for a different family.
Used in RFC 2616 RFC 2817 RFC 3546 RFC 4227 RFC 5922 RFC 5923 RFC 6066 RFC 7151 RFC 7671 RFC 7711 RFC 7712 RFC 9112
- Virtual Interface
A software abstraction representing the network link between a VPN client and gateway, created by the VPN software to hold the assigned IP addresses and traffic policies.
Like I'm five A pretend network connection that the VPN software creates to hold the addresses the gateway assigned you.
- Virtual link
A logical OSPF connection between two routers that are not directly attached, carried across the network using a reachable unicast address of the far endpoint.
Like I'm five A pretend direct cable between two routers that are really far apart.
- Virtual network
A network a provider offers a customer to use as though it were a physical network, though it is built from resources of underlying networks.
Like I'm five A pretend network made from pieces of a real one that you can use like your own.
- Virtual Network Identifier
A number carried in a tunnel header that says which virtual network a packet belongs to. Geneve gives it 24 bits, and the control plane decides what it means for forwarding.
Like I'm five A number on the envelope that tells which private network the letter belongs to.
- Virtual Network Topology
The topology formed by lower-layer LSPs that are advertised as traffic engineering links in the higher layer.
Like I'm five A map of shortcuts built on a lower floor that the upper floor can use as if they were roads.
- Virtual Private Network
A private network service built on top of shared infrastructure. Its members can use their own private address space, which may overlap with other networks.
Like I'm five A private club network that runs over shared wires, with its own set of names.
Used in RFC 2735 RFC 4026 RFC 4031 RFC 4176 RFC 4847 RFC 6513 RFC 6624 RFC 6867 RFC 6882 RFC 8049
- Virtual Private Network
An encrypted network tunnel that allows two devices to communicate securely over the internet as if they were on the same private network.
Like I'm five A secret tunnel between two computers so only they can read what they send each other.
Used in RFC 2764 RFC 4110 RFC 4923 RFC 5265 RFC 5684 RFC 6193 RFC 7359 RFC 9252 RFC 9375
- Virtual Reassembly Buffer
A table kept by a forwarding node that remembers where the fragments of each datagram come from and go to, so fragments can be passed on without storing the whole packet.
Like I'm five A small notebook of where each piece should go, instead of a big box to hold the whole message.
- Virtual Router
An abstract router, identified by a VRID and a set of IP addresses, that several physical routers on a LAN share. One of them acts for it at a time.
Like I'm five A pretend router that several real routers take turns being.
Used in RFC 2281 RFC 2338 RFC 2917 RFC 3768 RFC 5798 RFC 6527 RFC 9568
- Virtual Routing and Forwarding
A separate routing and forwarding table kept inside one router, so that different customers or services can be kept apart. Interfaces are assigned to a VRF.
Like I'm five Giving one router several separate address books, one for each customer.
- Virtual Routing and Forwarding (VRF)
A separate routing and forwarding table instance on a router, allowing multiple logical routers to coexist. Used in VPNs to isolate customer traffic.
Like I'm five A separate set of routing rules for each customer, so they do not see each other's traffic.
- VLAN
A virtual LAN, identified by a 12-bit VLAN ID, that splits one physical Ethernet network into separate logical networks.
Like I'm five Separate groups on the same network, like different classes sharing one school building.
Used in RFC 2613 RFC 2641 RFC 2674 RFC 3518 RFC 3619 RFC 4363 RFC 4554 RFC 4562 RFC 4675 RFC 4719 RFC 5517 RFC 5556 RFC 5603 RFC 6246 RFC 6325 RFC 6329 RFC 6439 RFC 6820 RFC 7172 RFC 7174 RFC 7348 RFC 7498 RFC 7796 RFC 8383 and 1 more
- Vocoder
A speech coder that turns voice into a small set of parameters that can be sent at a low bitrate, then rebuilds speech from them at the other end.
Like I'm five A machine that describes your voice in a few numbers, so a far-away machine can speak it again.
- Voice Activity Detection
A feature that detects when a speaker has stopped talking, used to reduce the amount of data sent during silence periods.
Like I'm five Noticing when someone stops talking so you can stop sending lots of sound data.
- VoIP
Voice over IP. Phone calls carried as packets over an IP network instead of a traditional telephone circuit.
Like I'm five Talking on the phone through the Internet.
Used in RFC 2543 RFC 2705 RFC 2719 RFC 2805 RFC 2824 RFC 2871 RFC 2995 RFC 3015 RFC 3219 RFC 3261 RFC 3326 RFC 3372 RFC 3389 RFC 3398 RFC 3432 RFC 3435 RFC 3495 RFC 3508 RFC 3523 RFC 3525 RFC 3603 RFC 3611 RFC 3660 RFC 3665 and 69 more
- Voucher
A signed statement from a manufacturer's signing service telling a new device the cryptographic identity of the domain it should trust. It is how a device learns its owner.
Like I'm five A signed note from the maker saying who a new gadget belongs to.
- VPLS
Virtual Private LAN Service. A provider service in which customer devices at different sites appear to be connected by a single LAN.
Like I'm five A pretend shared room where all your sites can talk to each other as if on one local network.
Used in RFC 4026 RFC 4665 RFC 7117 RFC 7209 RFC 7257 RFC 7309 RFC 7769 RFC 7796
- VRF
A VPN Routing and Forwarding table, a separate routing table kept on a router for one VPN. A single router can hold several VRFs at once.
Like I'm five A private address book on a router, one for each customer network.
Used in RFC 4364 RFC 4365 RFC 4382 RFC 4577 RFC 4659 RFC 5824 RFC 6016 RFC 6368 RFC 6514 RFC 6565 RFC 7024 RFC 7611 RFC 7674 RFC 7900 RFC 7956 RFC 8049 RFC 8299 RFC 8529 RFC 8994 RFC 9182
- VRRP
The Virtual Router Redundancy Protocol lets routers back each other up so that a backup takes over when the master fails. Version 3 covers both IPv4 and IPv6 and is defined in RFC 5798.
Like I'm five A team of routers where a spare steps in when the leader stops working.
- VTIMEZONE
The iCalendar component that describes a time zone, with STANDARD and DAYLIGHT sub-components giving the offsets and when they change.
Like I'm five A card that explains what a city's clock does through the year.
Used in RFC 2445 RFC 4791 RFC 4833 RFC 5545 RFC 5546 RFC 7529 RFC 7808 RFC 7809 RFC 7953 RFC 8984
- Vulnerability disclosure
The process by which someone who finds a security flaw reports it to the party responsible for the affected product or service, so that it can be fixed and, usually, announced.
Like I'm five Telling the owner of a shop that a lock is broken so they can fix it before a burglar finds it.
Used in RFC 1135 RFC 1244 RFC 2350 RFC 7495 RFC 8953 RFC 9116 RFC 9267