Network Flashcards
What is forwarding?
A process in which a packet arrives at a router then later output to the next router
What is routing
Determine the best route for packet delivery
What is VC & its characteristics?
- connection oriented data transmission
~ data transfer stays on source & destination path
~ requires buffer & bandwidth thus costly
What is datagram?
- connectionless data transmission in small units by all intermediate routers
~ packet consisting of destination address header
What are the routing algorithms?
- distance vector
- link state
- hierarchical
What are the 3 routing methods?
- Routing Information Protocol
- Open Shortest Path First
- Border Gateway Protocol
What is RIP & how it works
- Routing Information Protocol
~ determine best path via hop count
~ 1 router = 1 hop (max=15)
~ exchange with neighbour for 30s, after 180s no response, send new advertisement to new neighbour
~ < hop count = best path
What is OSPF & how it works?
- Open Shortest Path First
~ determine best path by mapping out networking link
~ gather link state information, map out network, network based on dest ip address, compute shortest path using Dijksha algorithm
What is BGP & how it works?
- Border Gateway Protocol
- determine path by exchanging routing & reachability among autonomous system
- information from iBGP & eBGP, advertise prefix & forward datagram
What is IPv4
- 32 bit address to identify host & network route
How to get IPv4 address?
Domain Host Configuration Protocol
- device connects to router
- device DHCP request is being encapsulated downwards
- request then receive by DCP server
- demux the request at server side
- DHCP ACK send from server which later encapsulated
- demux at client’s end which receive ip address
IPv4 subnet & NAT
- consists of 3 network subnet & 1 host subnet
- Network Address Translation
~ convert local address to public NAT address
what is IPv6?
-128 bit address
Why use IPv6?
solve IPv4 limitation & issues with NAT
What is IPv6 subnet?
- consists of 8 subnet portions
- 0/1 is 4 hexa bits = 16 bits
- has global subnet, subnet ID (organization) & interface ID (host)