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Flashcards in Network Layer Deck (18):
0

Main idea

Provides addressing

2

Four essential processes

1. Addressing
2. Encapsulation: creates packet with addressing info
3. Routing: selects best path for and directs packets toward destination
4. Decapsulation

3

IP use..

Is media independent; only packet size matters (maximum transmission unit)

4

Broadcast

A message sent from one host to all other hosts on network

5

Gateway router...

Delivers data to devices on remote network

6

Network layer supplies...

Network portion of address (this is how routers forward addresses between networks)

7

Hierarchical addressing

More subnets = fewer hosts
Network portion is the same

8

Default gateway

Forwards packets outside local network

9

Next hop address

Where to forward packet next; address of device that will process the packet next.

10

Ipconfig

View IP address of default gateway

11

No packet can't be forwarded without a route

Forwarding process is known as routing

Only indicates the next hop router to be forwarded, not final router

12

Three main features of routing table:

Destination network
Next hop address
Metric

13

Routing table commands

Netstat -r, route, routePRINT

14

Default route

Matches all destination networks

0.0.0.0

15

Packet forwarding

1. Layer 2 address is discarded for examination
2. Router at each hop only knows address of next hop

16

Static routing

Manually configured routes

17

Dynamic routing

Ex: RIP, OSPF, Enhanced Interior Gateway Routing Protocol

Adds overhead, consumes bandwidth; processed extensively by protocols

18

Ipv4 basic characteristics

Connection less, best effort, media independent (similar to UDP)

*requiring reliability overhead would consume bandwidth and increase delay*