Difference between revisions of "IPv6: Interior dan Exterior Gateway Protocol"

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Interior and Exterior Gateway Protocols
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Areas introduce a hierarchy to the network architecture. Another layer is added to this hierarchical structure by grouping areas into larger areas. These higher-level areas are called autonomous systems in the IP world and routing domains in the ISO world.
Areas introduce a hierarchy to the network architecture. Another layer is
+
 
added to this hierarchical structure by grouping areas into larger areas.
+
An autonomous system was once defined as a group of routers under a common administrative domain running a common routing protocol. Given the fluidity of modern networking life, the latter part of the definition is no longer very accurate. Departments, divisions, and even entire companies frequently merge, and networks that were designed with different routing protocols merge along with them. The result is that many networks nowadays combine multiple routing protocols with multiple degrees of inelegance, all under common administrations. So a contemporary definition of an autonomous system is a network under a common administration.
These higher-level areas are called autonomous systems in the IP world
+
 
and routing domains in the ISO world.
+
The routing protocols that run within an autonomous system are referred to as Interior Gateway Protocols (IGP). All the protocols given in this chapter as examples of distance vector or link state protocols are IGPs. Routing protocols that route between autonomous systems or routing domains are referred to as Exterior Gateway Protocols (EGP). Whereas IGPs discover paths between networks, EGPs discover paths between autonomous systems. Examples of EGPs include the following:
An autonomous system was once defined as a group of routers under a
+
 
common administrative domain running a common routing protocol.
+
Border Gateway Protocol (BGP) for IP
Given the fluidity of modern networking life, the latter part of the definition
+
Exterior Gateway Protocol (EGP) for IP (yes, an EGP named EGP)
is no longer very accurate. Departments, divisions, and even entire
+
The ISO's InterDomain Routing Protocol (IDRP)
companies frequently merge, and networks that were designed with
+
 
different routing protocols merge along with them. The result is that many
+
Novell also incorporates an EGP functionality, called Level 3 Routing, into NLSP.Having given these definitions, it must be said that the common usage of the term autonomous system is not so absolute. Various standards documents, literature, and people tend to give various meanings to the term. As a result, it is important to understand the context in which one is reading or hearing the term.
networks nowadays combine multiple routing protocols with multiple
+
 
degrees of inelegance, all under common administrations. So a
 
contemporary definition of an autonomous system is a network under a
 
common administration.
 
The routing protocols that run within an autonomous system are referred
 
to as Interior Gateway Protocols (IGP). All the protocols given in this
 
chapter as examples of distance vector or link state protocols are IGPs.
 
Routing protocols that route between autonomous systems or routing
 
domains are referred to as Exterior Gateway Protocols (EGP). Whereas
 
IGPs discover paths between networks, EGPs discover paths between
 
autonomous systems. Examples of EGPs include the following:
 
Border Gateway Protocol (BGP) for IP
 
Exterior Gateway Protocol (EGP) for IP (yes, an EGP named EGP)
 
The ISO's InterDomain Routing Protocol (IDRP)
 
Novell also incorporates an EGP functionality, called Level 3 Routing,
 
into NLSP.Having given these definitions, it must be said that the common usage of
 
the term autonomous system is not so absolute. Various standards
 
documents, literature, and people tend to give various meanings to the
 
term. As a result, it is important to understand the context in which one is
 
reading or hearing the term.
 
 
This book uses autonomous system in one of two contexts:
 
This book uses autonomous system in one of two contexts:
Autonomous system might refer to a routing domain, as defined at
+
 
the beginning of this section. In this context, an autonomous system
+
* Autonomous system might refer to a routing domain, as defined at the beginning of this section. In this context, an autonomous system is a system of one or more IGPs that is autonomous from other systems of IGPs. An EGP is used to route between these autonomous systems.
is a system of one or more IGPs that is autonomous from other
+
 
systems of IGPs. An EGP is used to route between these
+
* Autonomous system might also refer to a process domain, or a single IGP process that is autonomous from other IGP processes. For example, a system of OSPF-speaking routers might be referred to as an OSPF autonomous system. EIGRP also uses autonomous system in this context. Redistribution is used to route between these autonomous systems.
autonomous systems.
+
 
Autonomous system might also refer to a process domain, or a
+
The context will indicate which form of autonomous system is under discussion at different points throughout this book.
single IGP process that is autonomous from other IGP processes.
 
For example, a system of OSPF-speaking routers might be referred
 
to as an OSPF autonomous system. EIGRP also uses autonomous
 
system in this context. Redistribution is used to route between these
 
autonomous systems.
 
The context will indicate which form of autonomous system is under
 
discussion at different points throughout this book.
 
  
  

Latest revision as of 07:36, 23 March 2019

Areas introduce a hierarchy to the network architecture. Another layer is added to this hierarchical structure by grouping areas into larger areas. These higher-level areas are called autonomous systems in the IP world and routing domains in the ISO world.

An autonomous system was once defined as a group of routers under a common administrative domain running a common routing protocol. Given the fluidity of modern networking life, the latter part of the definition is no longer very accurate. Departments, divisions, and even entire companies frequently merge, and networks that were designed with different routing protocols merge along with them. The result is that many networks nowadays combine multiple routing protocols with multiple degrees of inelegance, all under common administrations. So a contemporary definition of an autonomous system is a network under a common administration.

The routing protocols that run within an autonomous system are referred to as Interior Gateway Protocols (IGP). All the protocols given in this chapter as examples of distance vector or link state protocols are IGPs. Routing protocols that route between autonomous systems or routing domains are referred to as Exterior Gateway Protocols (EGP). Whereas IGPs discover paths between networks, EGPs discover paths between autonomous systems. Examples of EGPs include the following:

Border Gateway Protocol (BGP) for IP
Exterior Gateway Protocol (EGP) for IP (yes, an EGP named EGP)
The ISO's InterDomain Routing Protocol (IDRP)

Novell also incorporates an EGP functionality, called Level 3 Routing, into NLSP.Having given these definitions, it must be said that the common usage of the term autonomous system is not so absolute. Various standards documents, literature, and people tend to give various meanings to the term. As a result, it is important to understand the context in which one is reading or hearing the term.

This book uses autonomous system in one of two contexts:

  • Autonomous system might refer to a routing domain, as defined at the beginning of this section. In this context, an autonomous system is a system of one or more IGPs that is autonomous from other systems of IGPs. An EGP is used to route between these autonomous systems.
  • Autonomous system might also refer to a process domain, or a single IGP process that is autonomous from other IGP processes. For example, a system of OSPF-speaking routers might be referred to as an OSPF autonomous system. EIGRP also uses autonomous system in this context. Redistribution is used to route between these autonomous systems.

The context will indicate which form of autonomous system is under discussion at different points throughout this book.


Pranala Menarik