Appendix A - VINES X.3 and X.25 Compliance with CCITT and Glossary
This appendix describes how VINES X.3 and X.25 complies with the CCITT 1984 definitions.
Table A-1 summarizes the VINES X.3 PAD parameter compliance with CCITT references. See the Banyan Asynchronous Terminal Emulation Guide for details.
Table A-2 summarizes the VINES X.25 compliance with CCITT references.
This glossary contains key terms that are used in the VINES Protocol Definition. If a specific word you are looking for is not defined in this glossary, we encourage you to use the Reader Comment card at the back of this document to let us know of the omission. Any comments you make will be considered in the future.
abort message A NetRPC message that a service returns to a client indicating the RPC aborted. The abort message header contains the reason.
address A description of the location of a node in a network.
acknowledgment packet A packet that IPC and SPP entities send to acknowledge the last packet containing user data received on a virtual connection.
Address Resolution Protocol (ARP) A VINES network layer protocol that assigns VINES internet addresses to client nodes.
address resolution client ARP software running in a node without a preassigned VINES internet address. Typically, the address resolution client runs in a client node.
See also address resolution service.
address resolution service ARP software running in a router with VINES IP route-through capabilities and a static 32-bit network ID.
See also address resolution client.
application layer protocols In the VINES architecture, the protocols that VINES applications use to communicate.
ARCNET modified token-passing LAN A LAN on which nodes communicate with the ARCNET modified token-passing protocol.
assignment request packet A packet that an address resolution client sends to an address resolution service requesting a VINES internet address.
See also assignment response packet.
assignment response packet A packet that an address resolution service sends to an address resolution client. The packet contains the client's VINES internet address.
See also assignment request packet.
backbone LAN A local area network, named for its physical and functional resemblance to a spine, that connects VINES servers to one another. Mainframe or host computers can also reside on a backbone, but, for efficient network performance, workstations should be placed on other LANS that are connected to a server.
block asynchronous protocol A data link layer protocol that enables VINES nodes to communicate asynchronously over point-to-point serial links. The block asynchronous protocol frames a block of data, as opposed to the traditional, character-oriented asynchronous protocol.
bridge A device that connects two physical networks using data link layer protocols. In most cases, the networks are of the same type, such as two Ethernet LANs.
A bridge spans two or more data links and performs protocol conversion on the data link layer (layer two of the OSI model). It uses information in the data link layer headers of frames to direct network traffic from one data link to another. Because bridges operate on the data link layer, they are faster than routers, which operate on the network layer.
Because a bridge does not logically separate data links (it only separates them physically) it can make multiple data links appear as one to nodes on the network. For example, a network in which multiple Token-Ring LANs are connected by IBM Token-Ring bridges appears as one LAN to the nodes on those LANs.
call message A NetRPC message that a client sends to a service, requesting a specific action from the service.
client An application program that accepts user requests and submits them to a service.
See also service.
client node A VINES node that requires the address resolution and routing services of a router.
See also router.
connection ID The identifier that IPC or SPP entities assign to a virtual connection.
connection record Information associated with a virtual connection.
CSMA/CD access method An industry-standard medium access method supported within the VINES data link layer. VINES nodes communicate over bus topologies, such as Ethernet, with this access method.
data link A direct, physical connection between two nodes, such as a LAN or serial line.
data link connectionless service A Logical Link Control service defined by the IEEE 802.2 LLC protocol. This service provides minimal recovery and sequencing but is useful when higher layers perform error recovery and sequencing functions.
data link connection-oriented service A Logical Link Control service defined by the IEEE 802.2 LLC protocol. This service provides comprehensive support for sequenced delivery of data and error recovery.
data link layer Layer two of the OSI model. The data link layer enables blocks of data to be transmitted from one device to another. It handles the transfer of data between devices and guarantees the integrity of the data being exchanged.
data link layer protocols In the VINES architecture, a set of protocols that manage communications over data links.
data packet A packet containing user data as part of an IPC reliable message or SPP message.
data stream service A transport layer service supporting the controlled flow of data between two processes. In the VINES architecture, SPP provides this service.
disconnect packet A packet with an SPP or IPC header that contains a request for disconnection.
echo frame A frame that the echo protocol on a node sends to determine if the node can communicate on the LAN.
echo packet A packet that ICP on a node sends to determine if a destination is reachable.
echo protocol A VINES diagnostic protocol for LANs.
error packet A packet containing an IPC header with communications failure information in the error field.
Ethernet LAN A LAN on which nodes communicate with the CSMA/CD access method.
See also CSMA/CD access method.
exception notification packet A packet that ICP sends to IPC or SPP entities indicating a packet could not be routed. The ICP header in this packet contains an exception field.
Fragmentation Protocol (FRP) A data link layer protocol that breaks up and reassembles packets. The FRP enables packets to be routed between media that support different frame sizes.
frame The unit of data sent over a data link.
gateway A device that connects two dissimilar network operating systems, file systems, or applications. In some applications, for example, TCP/IP, the term gateway is synonymous with router. See also router.
half-connection A point of reference that IPC and SPP entities use to manage a virtual connection.
header A unit of data containing information specific to a given protocol.
High-Level Data Link Control Protocol (HDLC) A data link layer protocol that VINES nodes use to communicate synchronously over point-to-point serial links.
hop A step in the transmission of data from one node to another node through an intermediate node. For example, if data on server 1 must pass through server 2 to reach server 3, it must take one hop. If it must pass through servers 2 and 3, to travel to server 4, it must take two hops.
hop count The number of intermediate nodes through which data must be transmitted to reach its destination.
IEEE 802.2 Logical Link Control standard An industry-standard link control and information transfer protocol, supported within the VINES data link layer.
IEEE 802.5 token-passing access method An industry-standard medium access method that is supported within the VINES data link layer. VINES nodes communicate over star-wired topologies, such as IBM Token-Ring, with this method.
IBM PC Network A broadband LAN on which nodes communicate with the IBM PC Network Adapter.
Integrated Services Digital Network (ISDN) A digital telecommunications network that supports the transmission of voice and data.
Internet Control Protocol (ICP) A VINES network layer protocol that provides support functions to certain transport layer service entities. ICP support includes providing notification on some network errors and topological conditions.
Interprocess Communications Protocol (IPC) A VINES transport layer protocol that provides unreliable datagram and reliable message service.
LAN (Local Area Network) A network that supports servers, workstations, printers, minicomputers, and mainframe computers that are connected over limited distances. Backbone LANs connect servers.
LAN card A hardware device that consists of electronic components of a LAN and a sheet of insulating material. It is the physical interface for a workstation to a VINES network.
LAN interface driver Software that provides access to the network interface hardware.
last forwarding node The node where a packet that generates a routing redirect packet or sequenced redirect packet originates.
See also preferred gateway; routing redirect packet; sequenced redirect packet.
Link Access Protocol Balanced (LAPB) The link access protocol that VINES uses for bit-synchronous communications over point-to-point HDLC serial lines and X.25 virtual circuits. LAPB enhances the bit-error-rate characteristics of common serial communications lines.
Link Access Protocol for the D-Channel (LAPD) The link access protocol that VINES uses for T1 server-to-server communications.
Level 2 of CCITT Recommendation X.25 See High-Level Data Link Control Protocol.
logical network A grouping of VINES nodes that share a common network ID in their VINES internet addresses.
MAC (Media Access Control) A set of IEEE data link layer standards for computer networks.
metric notification packet A packet containing a metric in the ICP header. IPC and SPP calculate the total path metric with this packet.
See also total path metric.
neighbor The relationship of one node to the other nodes that share a direct connection. For example, all nodes on an Ethernet LAN are neighbors.
neighbor entry An entry in the neighbor table.
See also neighbor table.
neighbor path A direct connection to a neighbor.
See also neighbor path entry.
neighbor path entry An entry in the neighbor table associated with a neighbor entry that identifies each neighbor path to the neighbor.
See also neighbor path.
neighbor table A routing table containing an entry for each neighbor and an entry for each direct connection to a neighbor.
NetRPC The VINES Remote Procedure Call mechanism that implements most session and presentation layer functions.
Network Driver Interface Specification (NDIS) A standard for writing network device drivers. With this standard, multiple protocol families use the same LAN card. For example, with NDIS, VINES 5.50 workstations can use both VINES and non-VINES protocols with the same LAN card.
network entry An entry in the network table containing information on the network topology.
See also network table; tuple.
network ID A 32-bit number that identifies a VINES logical network. The network ID is part of the VINES internet address.
See also VINES internet address.
network layer protocols In the VINES architecture, a set of protocols that manages the routing of packets between transport layers on two nodes. These nodes can be separated by multiple intermediate nodes and several data links.
network sequence number The router sequence number of the router in a logical network. The network sequence number is stored in the network entry for the router's logical network.
Compare with router sequence number; timestamp sequence number.
network table A routing table containing an entry for each known logical network.
See also network entry.
See also neighbor entry; neighbor path entry.
non-sequenced ARP An implementation of ARP designed to complement non-sequenced RTP.
Compare with sequenced ARP.
non-sequenced RTP The older of the two RTP implementations. Non-sequenced RTP provides fewer mechanisms for guaranteeing the integrity of routing table information than sequenced RTP.
Compare with sequenced RTP.
Omninet LAN A LAN on which nodes communicate with the Corvus Omninet LAN card.
packet The network layer unit of data sent over a path between network layer protocol entities on two nodes.
port A message queue that a communicating process uses to send and receive data.
port address A 64-bit address that communicating processes use to identify a port. A port address consists of the VINES internet address of the node where the port resides and a port number.
port number A number that uniquely identifies a port among the set of ports that a specific transport layer protocol supports.
preferred gateway A gateway providing the best route between the destination and the last forwarding node.
See also last forwarding node.
presentation layer protocols The rules and procedures for converting data formats between machine format and standard network representation. In the VINES architecture, NetRPC performs this function.
probe packet A packet that IPC and SPP entities use to respond to a sequencing error.
ProNET-10 LAN A LAN on which nodes communicate with the Proteon ProNET-10 adapter.
protocol A set of rules that defines how two applications or two sets of network equipment transfer data.
query request packet A packet that an address resolution client broadcasts to request a response from an address resolution service.
See also service response packet.
reject message A message that NetRPC returns to a client indicating a failure to process a Remote Procedure Call.
reliable message A transport layer unit of data consisting of a set of data packets (from one to four) that is transferred from one source port to one destination port. Reliable messages are acknowledged on delivery.
reliable message service A transport layer service that IPC provides to deliver and acknowledge reliable messages.
Remote Procedure Call (RPC) A NetRPC call that a client issues to request a service to perform a specific action.
return address message A NetRPC message that a service returns to a client in response to a search or search-all message. The return address message contains the service's port address.
return message A NetRPC message that returns the results of the Remote Procedure Call to the client. The results indicate successful completion of the processing of the service request.
router A node providing address resolution and routing services to client nodes and other routers. A router uses information from the network layer headers to direct network traffic from one data link to another, and to select the most effective routes to particular destinations.
See also client node.
router sequence number The sequence number that one router uses to validate the integrity of another router's routing information.
Compare with network sequence number; timestamp sequence number.
route-through service A routing service provided by routers and switches packets between different physical media.
routing metric A rough, round-trip delay time estimate in the path that maximum-sized VINES IP packets take to the router within the specified network.
routing decision The algorithm that VINES IP performs to route a packet.
routing redirect packet A non-sequenced RTP packet that a router sends to another node indicating the router should not be used as the gateway to a destination. The packet provides information on the appropriate gateway to reach the destination.
routing request packet A packet that non-sequenced RTP sends to request information on the network topology.
See also routing response packet; routing response.
routing response Routing information in one or more non-sequenced RTP response packets sent in response to a routing request packet.
See also routing request packet.
routing response packet A packet that non-sequenced RTP on a router sends to a client node in response to a request for routing information.
See also routing request packet; routing response.
routing server A router that assigns a VINES internet address to a client node.
See also client node.
routing table A table of information that allows VINES IP on client nodes and routers to make routing decisions. VINES has two routing tables: the neighbor table and the network table.
See also neighbor table; network table.
Routing Update Protocol (RTP) A network layer protocol that distributes routing information to support the routing services provided by VINES IP. RTP has two implementations: non-sequenced RTP and sequenced RTP.
See also non-sequenced RTP; sequenced RTP.
routing update Routing information contained in one or more non-sequenced routing update packets that keeps routing tables up-to-date.
See also routing update packet.
routing update packet A non-sequenced packet that propagates news of network changes and informs neighbors of each other's continued presence.
See also routing update.
search-all message A NetRPC message that a client uses to locate any instance of a distributed service.
search message A NetRPC message that enables a client to locate a particular type of distributed service.
sequenced ARP An implementation of ARP designed to complement sequenced RTP.
Compare with non-sequenced ARP.
Sequenced Packet Protocol (SPP) A transport layer protocol that provides a data stream service to communicating processes.
sequenced redirect packet A sequenced RTP packet that a router sends to another node indicating the router should not be used as the gateway to a destination. The packet provides information on the appropriate gateway to reach the destination.
sequenced re-initialization packet A sequenced RTP packet that a router broadcasts on all of its interfaces when it detects neighbor routers without the most up-to-date routing information about it.
sequenced request packet A sequenced RTP packet that client nodes and routers send to request routing information from other routers.
See also sequenced response.
sequenced response Routing information in one or more sequenced update packets sent in response to a sequenced request packet.
See also sequenced request packet; sequenced update packet.
sequenced RTP An RTP implementation that uses sequence numbers as a reliable means of maintaining routing tables.
sequenced update Routing information in one or more sequenced update packets that keeps routing tables up-to-date.
See also sequenced update packet.
sequenced update packet A sequenced update packet that propagates news of network changes, informs neighbors of each other's continued presence, and responds to sequenced request packets.
See also sequenced update.
service An application program that accepts user requests from a client.
See also client.
service response packet A packet that a router sends in response to a query request packet.
See also query request packet.
session layer protocols The rules and procedures that coordinate communications between processes. In the VINES architecture, the session layer transparently handles VINES socket communications, managing the conversion of ordinary local procedure calls from processes to IPC reliable messages on the VINES transport layer. NetRPC implements most session layer functions.
source-level routing A standard VINES feature that enables nodes (either workstations or servers) to communicate across IBM Token-Ring bridges.
subnetwork ID A 16-bit number that uniquely identifies a node within a VINES logical network.
See also VINES internet address.
timestamp sequence number A reference point based on the router sequence number when network information is stored.
Compare with network sequence number; router sequence number.
Token-Ring LAN A LAN on which nodes communicate with the IEEE 802.5 Token-passing access method. Examples of Token-Ring LANs include IBM Token-Ring and ProNET-4.
total path metric A connection record value indicating the total routing cost of reaching a destination.
See also metric notification packet.
transaction ID A parameter common to all NetRPC messages identifying the Remote Procedure Call to which the message applies.
transient port A port assigned on a rotating basis by IPC or SPP.
Compare with well-known port.
transport layer protocols In the VINES architecture, a set of protocols (SPP and IPC) that coordinate the end-to-end movement of data between two processes in the network.
tunneling A process by which packets traveling through non-VINES networks are enclosed, or encapsulated, in headers that are recognized by the network. Examples of tunneling include AppleTalk packets passing through a VINES network and VINES packets passing through a TCP/IP network.
tuple Information from a network entry contained in a non-sequenced or sequenced RTP packet.
See also network entry.
unreliable datagram A discrete unit of data limited in size that one process either transfers to another or broadcasts to a set of processes of the same type.
See also unreliable datagram service.
unreliable datagram service A transport layer service that does not order or acknowledge unreliable datagrams. In the VINES architecture, IPC provides this service.
See also unreliable datagram.
VINES internet address A 48-bit address that uniquely identifies a node in a VINES logical network. The address consists of a network ID and a subnetwork ID.
See also network ID; subnetwork ID.
VINES Internet Protocol (VINES IP) A VINES network layer protocol that moves packets through the network.
virtual connection Associations established between any two processes or IPC protocol entities in the network. The association is a two-way data pipe through which two processes or IPC protocol entities can exchange messages.
well-known port A port reserved for certain upper-layer services, such as the StreetTalk Service, and identified by a unique port number.
Compare with transient port.