RIP and OSFP Tutorial

There are few popular Routing Protocols like

(a) Distance Vector Protocol ( used by RIP )
(b) Link State Protocol ( used by OSFP )
(c) Path Vector Protocol ( used by EGP & BGP )

OSFP is going to replace RIP because OSFP create less traffic among the routers because it never continuously broadcast the routing table to each other ( broadcast among the routers ) , it only broadcast the routing table information if there is any change in the routing table .

OSFP create less traffic and improve bandwidth within the WAN ( WAN is formed by a group of routers to forward ( to route ) the packet from source to destinations .



Distance Vector Protocol
A simple routing protocol that uses distance or hop count as its primary measurement ( metric) for determining the best forwarding path.

This protocol ( distance vector protocol ) will use the shortest path ( less hop count , less distance ) to send
the packet to the destination .

This protocol , will calculate and determine the shortest path to send the packet to the destination

RIP, IGRP and EIGRP are examples for this protocol .

A distance vector protocol routinely ( frequently ) sends its neigboring routers copies of its routing tables to keep them up-to-date.

This protocol will send all the neigbouring routers’ routing table information to each other . To share the routing table among themselves .

In the other , this protocol will help the routers to update their routing table by sharing the routing table information among themselves .

Contrast with link state protocol and path vector protocol.


Link State Protocol
A complex routing protocol that shares information with other routers in order to determine the best path.

OSPF, NLSP and IS-IS are examples for this protocol .

Rather than continuously broadcast its routing tables as in a distance vector protocol, a link state protocol router only notifies its neighboring routers when it detects a change.

Contrast with distance vector protocol and path vector protocol.


Path Vector Protocol
A routing protocol, sometimes known as a policy routing protocol,

This protocol is used to span different autonomous systems.

[ span = determine the best path from source to destination ]

EGP and BGP are examples of this protocol .

The routing table maintains the autonomous systems that are traversed in order to reach the destination system.

Contrast with distance vector protocol and link state protocol.



Autonomous System
A network that is administered by a single set of management that are controlled by one person, group or organization.

Autonomous systems often use only one routing protocol, although multiple protocols can be used.

The core of the Internet is made up many autonomous systems.


Span =跨度 ; 翼展


Spanning Tree Algorithm

An algorithm used in transparent bridges

Spanning mean dynamically determines the best path from source to destination.

It avoids bridge loops (two or more paths linking one segment to another), which can cause the bridges to misinterpret results.

The algorithm creates a hierarchical "tree" that "spans" the entire network including all switches.

It determines all redundant paths and makes only one of them active at any given time.

The spanning tree protocol (STP) is part of the IEEE 802.1 standard.


OSPF
(Open Shortest Path First)

A routing protocol that determines the best path for routing IP traffic over a TCP/IP network.

OSPF is an interior gateway protocol (IGP), which is designed to work within an SAME autonomous system.

IGP ==> span within SAME autonomous system
EGP ===> span across FEW autonomous systems


It is also a link state protocol that provides less router to router update traffic than the RIP protocol (distance vector protocol) à Less update to each other ( routers ) so, it create LESS traffic and wouldn’t waste the bandwidth.

Only notifies its neighboring routers when it detects a change in routing table . It wouldn’t simply broadcast the routing table to their neighboring routers . -à save bandwidth , less traffic if compare to RIP

OSPF is designed to replace RIP .


EGP
(Exterior Gateway Protocol)

A broad category of routing protocols that are designed to span different autonomous systems. Contrast with IGP.


BGP
A routing protocol that is used to span autonomous systems on the Internet.

It is a robust, sophisticated and scalable protocol that was developed by the Internet Engineering Task Force (IETF).

BGP4 supports the CIDR addressing scheme, which has increased the number of available IP addresses on the Internet.

BGP was designed to supersede ( replace ) EGP.

It is also known as a path vector protocol. See CIDR and routing protocol.


CIDR
(Classless Inter-Domain Routing)

A method for creating additional addresses on the Internet, which are given to Internet service providers (ISPs) that in turn delegate them to their customers.

CIDR reduces the burden on Internet routers by aggregating routes so that one IP address represents thousands of addresses that are serviced by a major backbone provider.

All packets sent to any of those addresses are sent to the ISP . In 1990, there were about 2,000 routes on the Internet. Five years later, there were more than 30,000.

Without CIDR, the routers would not have been able to support the increasing number of Internet sites.

Instead of the fixed 8, 16 and 24 bits used in the Class A-B-C network IDs, CIDR uses a variable network ID from 13 to 27 bits. For example, the CIDR address 204.12.01.42/24 indicates that the first 24 bits are used for network ID. See IP address.



RIP
(Routing Information Protocol)
A simple routing protocol that is part of the TCP/IP protocol suite.

It determines a route based on the smallest hop count between source and destination.

RIP is a distance vector protocol that routinely broadcasts routing information to its neighboring routers and is known to waste bandwidth.

AppleTalk, DECnet, TCP/IP, NetWare and VINES all use incompatible versions of RIP.


Routing Protocol
A formula used by routers to determine the appropriate path onto which data should be forwarded.

The routing protocol also specifies how routers report changes and share information with the other routers in the network that they can reach.
A routing protocol allows the network to dynamically adjust to changing conditions, otherwise all routing decisions have to be predetermined and remain static. See router, routing table, RIP, OSPF, IGRP, EGP and BGP.