In the early years of networking and network expansion, RIP was considered the best routing protocol and was well suited to the needs of the era, but after a successful network experience and public acceptance, computer networks Size and surface coverage began to grow, and naturally, new and more efficient routing tools were needed. Networks require more routers, more stability, and less convergence of routing tables and less constraints. A clear and precise example: The 15-step restriction in the RIP protocol draws designers to the development of a network.
Therefore, business networks came together and tried to connect and integrate their distributed environments, and RIP was not usable for these environments.
But at the end of the 80's, the golden age of the Internet was emerging in the era of technology-free technology, and new protocols should be developed to meet the needs of a widespread and integrated network: protocols that go beyond stability, convergence, and speed It's also easy to configure, maintain, and understand.
By the mid-eighties, Cisco had tried to design a new protocol based on the core of the RIP protocol, with fewer restrictions than RIP. This protocol, called IGRP (Interior Gateway Routing Protocol), was expanded shortly after the release, and was named "EIGRP".
These two protocols are the key to inter-domain routing.
This topic is dedicated to the IGRP-EIGRP protocols. First, we'll go a little bit to the technology used in these protocols, and then explain the configuration and operational method in later sections.
Important parts:
1-EIGRP and EIGRP compared to the RIP protocol
2-IGRP technology
3-Configure IGRP
4- EIGRP technology
5- Configuring EIGRP
Since the basis of both the IGRP and EIGRP protocols are based on the RIP protocol, the best way to review them is to describe their features and characteristics compared to the RIP.
IGRP and EIGRP compared to RIP
RIP An internal Routing protocol: This means that it has the task of directing and routing data packets in a single, independent environment. RIP is not designed for environments that require the transfer of data packets between multiple independent networks with different management structures and policies.
Example: The RIPs that belong to the RIP can not be connected to two independent universities (each of which consists of multiple internal networks, routers, and independent management).
RIP is a prototype designed to be fast, uncomplicated, and operational, designed for small and one-handed environments, and has many limitations and limited capabilities. This is a general principle that one can not design a protocol that works well in any environment and in any environment.
The IGRP is in fact the scientific and operational development of the RIP protocol, but it still remains an internal routing protocol and is not used for routing between independent environments. IGRP aims to develop an independent and integrated network environment and optimized routing.
For example, based on the IGRP, an organization's network can be expanded to any degree. The IGRP designers added new terminology and definitions to the routing literature, including the concept of an "autonomous network." Autonomous System or Autonomous Network is a large network with specific purposes and uses, and is supervised and supervised by a specific organization or organization. Within an autonomous grid, there are other small and large networks, all of which use routing elements and common protocols to connect to each other.
For example, a university can provide itself an AS network, so that each college has at least one local area network. These local networks are connected to the router according to the discretion of the network manager.
Configuration and management of routers are typically the same, and are within the scope of the responsibilities of the AS network. Changes in the network configuration or network topology and the removal or addition of routers with permissions and network monitoring will be possible. The network administrator is responsible for defining the "subnet mask pattern" and setting up routers in such a way that routing within the network under his supervision is done correctly. Naturally, such an independent network is considered to be independent, and even if it is connected to another network, one can not change its outsourcing routing policies.
An autonomous network operator can operate on a network under its own control of "authority" (autority), which can be applied to each individual network component (host machine), network topology, operating system, communication infrastructure design, and network connection method Localization and type of routing protocol and influence their views.
Routing IP packets within a more autonomous network is a function of parameters such as the speed and reliability of the routing algorithm. Now assume that autonomous networks are connected through a very fast and universal communication infrastructure. The routing of packets on the shah The ways that connect AS networks are completely different from routing within an autonomous network. In routing between AS networks, issues such as security, payment of subscription rights and policy can also be involved in choosing the best route.
Another new term in the gateway network literature is that it will mean something more than a router. "Gateway" is a router that operates routing between two or more independent network environments (multiple ASs). Due to the fact that in each of these independent networks, some management and routing systems have been implemented, so the gateway role for routing between AS networks, where no control and variation within it is possible, is different from that of routers. Figure 1-1 shows an Independent As network with a gate.
Most gates are routers that link the As network to an Internet or Internet organization. The Internet is a massive and fast communication structure that guides and routes packets between As networks. In the following lessons, we will describe the role of "gateway" and its technology.
