Routing Fundamentals Flashcards

Flashcards on Routing Fundamentals, Data Encapsulation, and Network Communication

Encapsulation

A process wherein a new string of information is added to an existing unit to form a new unit of information.

Decapsulation

The reverse process of encapsulation wherein the header and tail of a packet are removed to obtain the data payload.

Packet

A data unit that is exchanged and transmitted on a network, in the format of header+data payload+tail.

Header

The information segment added before the data payload during packet assembly to facilitate information transmission.

Tail

The information segment added after the payload to facilitate information transmission.

Protocol Data Unit (PDU)

A specific block of information transferred over a network. It describes the different types of data that are transferred from each layer in the OSI model.

Internet Protocol (IP)

Defines a packet and an addressing scheme, transfers data, and routes packets to remote hosts.

Internet Control Message Protocol (ICMP)

A TCP/IP protocol that handles errors and controls the process of sending data between computers.

Internet Group Management Protocol (IGMP)

A TCP/IP protocol that handles multicasting; hosts use it to keep local routers apprised of their membership in multicast groups.

Address Resolution Protocol (ARP)

A TCP/IP protocol that obtains the physical address of a node from a specific IP number.

Reverse Address Resolution Protocol (RARP)

A TCP/IP protocol that allows a host with no local permanent data storage media to find its Internet address given its physical address.

Ethernet

A family of LANs covered by a group of IEEE 802.3 standards; a best-effort delivery system that uses a CSMA/CD access method.

Point-to-Point Protocol (PPP)

The protocol used for data transfer across a serial line.

Fiber distributed data interface (FDDI)

A set of ANSI protocols for sending digital data over fiber optic cable.

Asynchronous Transfer Mode (ATM)

A wide area protocol that features high data rates and equal-sized packets/cells suitable for text, audio, and video data transfer.

Frame Relay

A WAN protocol for LAN internetworking that provides a fast and efficient method of transmitting information across multiple switches and routers.

Proxy ARP

A protocol used when a network terminal needs to pass data from one segment to another without changing its current IP address information.

Routing

The the basic element of data communication networks, which process of selecting paths on a network along which packets are sent from a source to a destination.

Path determination

Enables a router to compare the destination address to the available routes in its routing table and to select the best path.

Routes

Path information used to guide packet forwarding.

Routing device (Router)

A network device that forwards packets to a destination subnet based on routes, and maintains an IP routing table.

Packet routing

The overall network-wide process of finding the most efficient path for forwarding the IP packet from source to destination through the use of network routing tables, protocols, and algorithms.

Destination

Identifies a destination subnet.

Mask

Identifies a subnet together with a destination IP address.

Outbound interface

Indicates the interface through which a data packet is sent out of the local router.

Next hop

Indicates the next-hop address used by the router to forward the data packet to the destination subnet.

Packet Forwarding

Passing or moving of information between interfaces.

Direct Delivery

Occurs when the IP node forwards a packet to its final destination in the network.

Indirect Delivery

Occurs when the IP node forwards a packet to an intermediate node because the final destination is not on a directly attached network.

Routing Table

A database that contains information about which router network interface or port to place information to send it to a particular network segment.

Destination/Mask

Indicates the destination network address and mask of a specific route.

Protocol (Proto)

Indicates the protocol type of the route.

Preference (Pre)

Indicates the routing protocol preference of the route and is used to compare routes from different routing protocols.

Cost

Indicates the cost of the route, also known as the metric.

Next Hop

Indicates the local router’s next-hop address of the route to the destination network.

Interface

Indicates the outbound interface of the route.

Direct routes

Automatically generated by devices and point to local directly connected networks.

Static routes

Manually configured by network administrators.

Dynamic routes

Learned by dynamic routing protocols running on routers.