ARP
Purpose of ARP:
Used to mediate between ethernet (or other broadcast link-level protocols) and the network layer, or IP protocols.
Difference between IPv4 and IPv6
IPv4
Has 32-bit address length
IPv6
Supports manual and DHCP configuration
Has 128-bit address length
Supports auto-configuration and renumbering
End-to-end connection integrity is unachievable
End-to-end connection integrity is achievable
Encryption and authentication is not provided
Encryption and authentication is provided
Has a broadcast message transmission scheme
Has Multicast and Anycast message transmission scheme
Q: . Explain why the IPv4 protocol requires other layers to provide reliability.
A: The protocol does not provide any functionality for error recovering for datagrams that are either duplicated, lost or arrive to the remote host in another order than they are send.
Checksumfield is available
Sender and forwarding routers performs fragmentation
Checksumfield is not available
Q: Explain how network devices use routing tables to direct packets to a destination network.
Fragmentation is performed only by the sender
Security features relies on application
Has an inbuilt security feature named IPSEC
- When a data packet comes to a router port, the router reads address information in packet to determine out which port the packet will be sent.
- When a packet arrives at a Router, it examines destination IP address of a received packet and make routing decisions accordingly.
- A routing table lists all networks for which routes are known.
- If there’s a match, the packet is forwarded using the specified information in the routing table.