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.