7. Routing

Router

A device that sends packets from one network to another.

20, 170, 5

Administrative Distance BGP external = ______ EIGRP external = ______ EIGRP summary = ______

0, 200, 115

Administrative Distance Connected interface or static route = ______ BGP Internal = ______ IS-IS = ______

90, 100, 120

Administrative Distance EIGRP internal = ______ IGRP = ______ RIP = ______

255, 1, 110

Administrative Distance Unknown Source = ______ Static Route to an IP address = ______ OSPF = ______

Network Address Translation (NAT)

Allows you to connect a private network to the internet without obtaining registered addresses for every host.

Network

Can be defined as a broadcast domain where all the hosts have the same ______ portion in their IP address.

Header

Contains source and destination IP addresses

Payload

Depends on the protocol that formed the packet

Hop

Distance Vector Routing Protocol Are generally measured by ______ count

False

Distance Vector Routing Protocol T or F Doesn't share any routing information

True

Distance Vector Routing Protocol T or F Will only share information with its direct neighbors (the next hop routers)

True

Distance Vector Routing Protocol T or F Will send route information at a regularly scheduled time

Direction

Distance Vector Routing Protocol ______ refers to the network interface that is used to forward the IP packet to the distant network.

Port Address Translation (PAT)

How NAT Works Allows multiple private hosts to share a single public address

NAT Router

How NAT Works Hosts on the private network share the IP addresses of the ______ ______ or a pool of address assigned for the network.

False

How NAT Works T or F NAT associates multiple public addresses with a single private address.

True

How NAT Works T or F NAT is usually synonymous with PAT

Port

How NAT Works Technically speaking, NAT translates one address to another. ______ address translation associates a port number with the translated address.

Private, Internet, Forward

How NAT Works The NAT router maps port numbers to ______ IP addresses. Responses to ______ requests include the port number appended by the NAT router. This allows the NAT router to ______ responses back to the correct private host.

DHCP (Dynamic Host Configuration Protocol)

Implementing NAT A NAT router can act as a limited-function ______ server, assigning addresses to private hosts

DNS (Domain Name System)

Implementing NAT A NAT router can forward ______ requests to the internet

Security

Implementing NAT NAT provides some ______ for the private network because it translates or hides private addresses.

5,000

Implementing NAT NAT supports a limit of ______ concurrent connections

Exterior

Interior and Exterior Routing Done between autonomous systems. Organizations that connect their private networks to the internet are assigned a unique autonomous system number, or ASN. 1. The routing performed by the so-called internet backbone 2. Will be limited to a single router that connects the organizations network to the internet via an ISP 3. Larger organizations or organizations with a critical mission may have multiple ISPs that give them redundant internet connectivity. In this case, the edge router or routers must run an ______ routing protocol.

Interior

Interior and Exterior Routing Done with an autonomous system (AS) 1. You own and control the routers 2. You determine where the routers are located 3. You control the interfaces that connect the routers to your network 4. You determine which ______ routing protocols are enabled.

Circular

Link-State Routing Protocol A smart flooding algorithm prevents looping when there are ______ routing paths.

Status, Connection, Bandwidth, Delay

Link-State Routing Protocol The metric value is based on the ______ and ______ type of the link. The metric value may also include other factors, such as ______ and ______

Looping

Link-State Routing Protocol To eliminate ______, each router forwards the packet to every neighbor except the one it received the packet from

Map

Link-State Routing Protocol Using converged route information, the router constructs a complete ______ of the routing topology.

Throughput

Routing Metrics Although the advertised bandwidth is the max capacity of a link, its actual ______ will be less due to latency and other network overhead. If used in the cost calculation, larger ______ will contribute to a lower cost.

Reliability

Routing Metrics Measured by how often the path is down.

Bandwidth

Routing Metrics Network ______ measures the capacity of a link. If ______ is a factor in the cost, a link with a lower capacity will have a higher cost that a link with high ______.

Load

Routing Metrics Refers to the amount of computational work that it performs. Links for routers that are performing under heavy ______ will have a higher cost.

Maximum Transmission Unit (MTU)

Routing Metrics Setting on a router that determines the maximum payload size for a frame.

Latency

Routing Metrics The delay in transmissions over the path.

Hop Count

Routing Metrics The distance between networks can be measured in ______, or the number of times a router forwards an IP packet from one network to another. For a directly connected link, the ______ will be zero.

Link Utilization

Routing Metrics The percentage of a network's bandwidth that is currently being consumed by network traffic.

Packet Loss

Routing Metrics This occurs when IP packets fail to reach their destination. If it is used in calculating the cost, a link that experiences greater ______ will have a higher cost.

Routing Table

Routing Terms A database of entries, each with 1. Address of a known network 2. The next hop gateway 3. The network interface to reach the next hop gateway 5. A metric or cost that indicates the desirability of the route

Default Route

Routing Terms An entry of 0.0.0.0 in a routing table. This entry matches every network. If no other entry in the routing table matches the destination IP address in a packet, the router will send the packet to the gateway found in the ______ ______ If a ______ ______ does not exist, the router will drop any packets that do not match an entry in a routing table.

Loopback Entry

Routing Terms Contains ______ addresses which are used for diagnostics and for troubleshooting the TCP/IP stack.

Next Hop

Routing Terms To forward a packet, a router only needs to know ______ ______ information, not the full path to the ultimate destination. The gateway that the router will send the packet to.

Static

Static and Dynamic Routing ______ routing entries are manually added to the routing table 1. A route entry of 0.0.0.0 identifies the default entry or default route which is a special form of a ______ entry 2. ______ entries remain in the routing table until they are manually removed 3. ______ routing works well in smaller networks

Dynamic

Static and Dynamic Routing ______ routing is implemented by enabling a routing protocol

Packet

The payload of an OSI layer 2 frame Has a header and a payload.

Routing

The process of moving packet from one network to another using routers

Hybrid

There is only one popular exterior routing protocol, and it is a ______ protocol.

Frame, Payload, Header, Destination, Next Hop

To perform routing, a router: 1. Receives a ______ 2. Opens the frame's ______, which is an IP packet 3. Reads the packet ______ to find IP addressing information 4. Matches the ______ network address with entries in its routing table creates a new frame using the packet as a payload 5. Transmits the new frame to the ______ ______ gateway

Link-State

Type of Routing Protocol 1. Also known as shortest path protocols. 2. The router examines its directly connected network links and assigns a metric value 3. The router determines the neighbor routers that are connected by each direct network link 4. The router builds a link-state packet (LSP) that contains a list of its neighbors and the metric value of the link to that neighbor 5. The router sends the LSP to its neighbor routers. 6. Neighboring routers, in turn, sends the LSP to its neighbors, and so on

Routing Information Protocol (RIP)

Type of Routing Protocol A distance vector routing protocol used for routing within an autonomous system Network size is limited to a max of 15 hops between any two networks. ______ v1 is a classful protocol. ______ v2 is a classless protocol.

Enhanced Interior Gateway Routing Protocol (EIGRP)

Type of Routing Protocol A hybrid routing protocol developed by CIsco for routing within an AS. uses a composite number for the metric, which indicates bandwidth and delay for a link.

Open Shortest Path First (OSPF)

Type of Routing Protocol A link-state routing protocol used for routing within an AS. Divides a large network into areas.

Border Gateway Protocol (BGP)

Type of Routing Protocol An advanced distance vector protocol. An exterior gateway used for routing between autonomous systems. Uses paths, rules, and policies instead of a metric for making routing decisions.

Distance Vector

Type of Routing Protocol Sets a metric value or cost based on how far away a network is. Sets a direction that is associated with the distance

Intermediate System to Intermediate System (IS-IS)

Type of Routing Protocol a link-state routing protocol used for routing within an AS. Divides a large network into areas. There is no area 0 requirement, and ______ provides greater flexibility for creating and connecting areas than OSPF

Dynamic NAT

Types of NAT Allows internal (private) hosts to contact external (public) hosts, but not vice versa---external hosts cannot initiate communications with internal hosts.

Static NAT (SNAT)

Types of NAT Maps a single private IP address to a single public IP address on the NAT router. Used to take a server on the private network (such as a web server) and make it available on the internet

Dynamic & Static NAT

Types of NAT Where two IP addresses are given to the public NAT interface, allows traffic to flow in both directions

Convergence

______ occurs when all routers share a consistent view of the network.