Operation of IP Data Networks
The IP protocol or internet protocol is the principal
communications protocol in the Internet Protocol suite. It’s used for relaying
datagrams across network boundaries. Its routing function enables
internetworking and essentially establishes the internet.
IP is the primary protocol in the internet layer of the Internet
Protocol suite has the task of delivering packets from the source host to the
destination host solely based on the IP address in the packet headers.
As you can see IP is the highest layer protocol which is
implemented on both routers and hosts. The delivery service associated
with IP is minimal.
IP provides an unreliable, connectionless, best effort service
also called Datagram service.
·
Unreliable: IP does not make an
attempt to recover lost packets.
·
Connectionless: Each
packet is handled independently IP is not aware that packets between hosts may
not be sent in logical Sequence.
·
Best-effort: IP does not make
guarantees on the service (no throughput guarantee, no delay guarantee)
The consequences of this is that higher-level protocols have to
deal with losses or duplicate packets and packets may be delivered out of
sequence.
IP supports the following
services
·
one-to-one communication or unicast
·
communication 1 – all communication or broadcast communication
·
1 to several communication or multicast communication
That being said IP multicast requires the support of other
protocols such as IGMP or multicast routing.
As I mentioned before IP is unreliable and connection less.
It relies on higher-level protocols such as TCP and UDP to ensure packets have
no errors and that all packets arrive and are correctly reassembled.
Out of the two protocols that are used, the first one is UDP.
·
UDP provides unreliable connectionless delivery servicing the
Internet Protocol.
·
Application programs utilizing UDP accept full responsibility
for packet reliability including message loss delay and out of sequence packets
With transmission
control protocol or TCP
·
TCP provides a reliable connection-oriented service using the
Internet Protocol
·
It provides reliable packet delivery, packet sequencing, error
control and multiplexing
No comments:
Post a Comment