Onnowpurbo at 02:14, 24 March 2019

2019-03-24T02:14:00Z

← Older revision		Revision as of 02:14, 24 March 2019
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	Chapter 2. Introduction to Border Gateway Protocol 4		Chapter 2. Introduction to Border Gateway Protocol 4

	This chapter covers the following key topics:		This chapter covers the following key topics:
	Classless Interdomain Routing This section introduces CIDR and discusses both its advantages and its shortcomings.
	Who Needs BGP? This section examines several inter-AS scenarios, with an eye to where BGP is necessary and where it is		* Classless Interdomain Routing This section introduces CIDR and discusses both its advantages and its shortcomings.
	not.		* Who Needs BGP? This section examines several inter-AS scenarios, with an eye to where BGP is necessary and where it is not.
	BGP Basics This section discusses the fundamentals of the Border Gateway Protocol, including message types and path		* BGP Basics This section discusses the fundamentals of the Border Gateway Protocol, including message types and path attributes.
	attributes.		* IBGP and IGP Synchronization This section presents the issues surrounding synchronization between IBGP and the IGP within an AS, why synchronization is required by default, and how synchronization problems can be avoided.
	IBGP and IGP Synchronization This section presents the issues surrounding synchronization between IBGP and the IGP		* Managing Large-Scale BGP Peering This section presents four tools for controlling large-scale BGP implementations.
	within an AS, why synchronization is required by default, and how synchronization problems can be avoided.		* BGP Message Formats This section examines the details of the various BGP messages.
	Managing Large-Scale BGP Peering This section presents four tools for controlling large-scale BGP implementations.		* Border Gateway Protocol (BGP) is a particularly important topic for any CCIE, and you can expect your knowledge of it to be thoroughly challenged in the CCIE lab.
	BGP Message Formats This section examines the details of the various BGP messages.
	Border Gateway Protocol (BGP) is a particularly important topic for any CCIE, and you can expect your knowledge of it to be		You learned in Chapter 1, "Exterior Gateway Protocol," that the architects of the ARPANET began recognizing in the early 1980s that autonomous systems, and an inter-AS reachability protocol, were necessary to maintain manageability of the fast-growing Internet.
	thoroughly challenged in the CCIE lab.
	You learned in Chapter 1, "Exterior Gateway Protocol," that the architects of the ARPANET began recognizing in the early 1980s that		Their original solution, Exterior Gateway Protocol (EGP), was adequate for the backbone-based ARPANET, but from the beginning, the architects understood the necessity of moving to a meshed inter-AS topology. They further understood that EGP was not capable of efficiently routing in such an environment because of its inability to detect loops, its very slow convergence time, and its lack of tools
	autonomous systems, and an inter-AS reachability protocol, were necessary to maintain manageability of the fast-growing Internet.
	Their original solution, Exterior Gateway Protocol (EGP), was adequate for the backbone-based ARPANET, but from the beginning,
	the architects understood the necessity of moving to a meshed inter-AS topology. They further understood that EGP was not capable
	of efficiently routing in such an environment because of its inability to detect loops, its very slow convergence time, and its lack of tools
	to support routing policies.		to support routing policies.
	Attempts were made to enhance EGP, but in the end, an entirely new inter-AS protocol, a true routing protocol rather than a mere
	reachability protocol such as EGP, was called for. That inter-AS routing protocol, first introduced in 1989 in RFC 1105[1], is BGP. The		Attempts were made to enhance EGP, but in the end, an entirely new inter-AS protocol, a true routing protocol rather than a mere reachability protocol such as EGP, was called for. That inter-AS routing protocol, first introduced in 1989 in RFC 1105[1], is BGP. The first version of BGP was updated exactly one year later in RFC 1163[2]. BGP was upgraded again in 1991 in RFC 1267[3], and with this third modification, it became customary to refer to the three versions as BGP-1, BGP-2, and BGP-3, respectively.
	first version of BGP was updated exactly one year later in RFC 1163[2]. BGP was upgraded again in 1991 in RFC 1267[3], and with
	this third modification, it became customary to refer to the three versions as BGP-1, BGP-2, and BGP-3, respectively.		The current version of BGP, BGP-4, was introduced in 1995 in RFC 1771[4]. BGP-4 differs significantly from the earlier versions. The most important difference is that BGP-4 is classless, whereas the earlier versions are classful. The motive for this fundamental change goes to the very heart of the reason exterior gateway protocols exist at all: to keep routing within the Internet both manageable and
	The current version of BGP, BGP-4, was introduced in 1995 in RFC 1771[4]. BGP-4 differs significantly from the earlier versions. The		reliable. Classless interdomain routing (CIDR) originally introduced in RFC 1517[5] in 1993, finalized in RFC 1519[6] in the same year as a standard proposal, and amended by RFC 1520[7] was created for this purpose, and BGP-4 was created to support CIDR.
	most important difference is that BGP-4 is classless, whereas the earlier versions are classful. The motive for this fundamental change
	goes to the very heart of the reason exterior gateway protocols exist at all: to keep routing within the Internet both manageable and
	reliable. Classless interdomain routing (CIDR) originally introduced in RFC 1517[5] in 1993, finalized in RFC 1519[6] in the same year
	as a standard proposal, and amended by RFC 1520[7] was created for this purpose, and BGP-4 was created to support CIDR.

Onnowpurbo: Created page with "Chapter 2. Introduction to Border Gateway Protocol 4 This chapter covers the following key topics: Classless Interdomain Routing This section introduces CIDR and discusses..."

2019-03-18T04:21:03Z

Created page with "Chapter 2. Introduction to Border Gateway Protocol 4 This chapter covers the following key topics: Classless Interdomain Routing This section introduces CIDR and discusses..."

New page

Chapter 2. Introduction to Border Gateway Protocol 4
This chapter covers the following key topics:
Classless Interdomain Routing This section introduces CIDR and discusses both its advantages and its shortcomings.
Who Needs BGP? This section examines several inter-AS scenarios, with an eye to where BGP is necessary and where it is
not.
BGP Basics This section discusses the fundamentals of the Border Gateway Protocol, including message types and path
attributes.
IBGP and IGP Synchronization This section presents the issues surrounding synchronization between IBGP and the IGP
within an AS, why synchronization is required by default, and how synchronization problems can be avoided.
Managing Large-Scale BGP Peering This section presents four tools for controlling large-scale BGP implementations.
BGP Message Formats This section examines the details of the various BGP messages.
Border Gateway Protocol (BGP) is a particularly important topic for any CCIE, and you can expect your knowledge of it to be
thoroughly challenged in the CCIE lab.
You learned in Chapter 1, "Exterior Gateway Protocol," that the architects of the ARPANET began recognizing in the early 1980s that
autonomous systems, and an inter-AS reachability protocol, were necessary to maintain manageability of the fast-growing Internet.
Their original solution, Exterior Gateway Protocol (EGP), was adequate for the backbone-based ARPANET, but from the beginning,
the architects understood the necessity of moving to a meshed inter-AS topology. They further understood that EGP was not capable
of efficiently routing in such an environment because of its inability to detect loops, its very slow convergence time, and its lack of tools
to support routing policies.
Attempts were made to enhance EGP, but in the end, an entirely new inter-AS protocol, a true routing protocol rather than a mere
reachability protocol such as EGP, was called for. That inter-AS routing protocol, first introduced in 1989 in RFC 1105[1], is BGP. The
first version of BGP was updated exactly one year later in RFC 1163[2]. BGP was upgraded again in 1991 in RFC 1267[3], and with
this third modification, it became customary to refer to the three versions as BGP-1, BGP-2, and BGP-3, respectively.
The current version of BGP, BGP-4, was introduced in 1995 in RFC 1771[4]. BGP-4 differs significantly from the earlier versions. The
most important difference is that BGP-4 is classless, whereas the earlier versions are classful. The motive for this fundamental change
goes to the very heart of the reason exterior gateway protocols exist at all: to keep routing within the Internet both manageable and
reliable. Classless interdomain routing (CIDR) originally introduced in RFC 1517[5] in 1993, finalized in RFC 1519[6] in the same year
as a standard proposal, and amended by RFC 1520[7] was created for this purpose, and BGP-4 was created to support CIDR.

==Pranala Menarik==

* [[IPv6: Advanced Routing]]

IPv6: BGP - Revision history

Onnowpurbo at 02:14, 24 March 2019

Onnowpurbo: Created page with "Chapter 2. Introduction to Border Gateway Protocol 4 This chapter covers the following key topics: Classless Interdomain Routing​ This section introduces CIDR and discusses..."

Onnowpurbo: Created page with "Chapter 2. Introduction to Border Gateway Protocol 4 This chapter covers the following key topics: Classless Interdomain Routing This section introduces CIDR and discusses..."