Overview: Border Gateway Protocol (BGP) Tại thời điểm này, Internet nắm giữ hơn các tuyến đường, mà là nhiều hơn so với giao thức cổng nội thất (IGPs) như EIGRP hay OSPF được thiết kế để xử lý. Ngoài ra, trong khi một mạng tư nhân thường có chỉ là một vài con đường có thể, với Internet, có nghĩa là có thể có hàng ngàn cách khác nhau để đi đến cùng một đích đến. EIGRP hoặc OSPF sẽ có vấn đề lớn trong những trường hợp này. Rõ ràng, một giao thức khác là cần thiết để. | Chapter 10 Overview Border Gateway Protocol BGP Solutions in this chapter The History of BGP Maximizing the Functionality of BGP External BGP and the Internet The BGP Path Selection Process Redistributing BGP into Your IGP Defining Internal BGP Route Reflectors and Confederations Advanced BGP Network Design 375 376 Chapter 10 Overview Border Gateway Protocol BGP Introduction As at press time the Internet holds well over 90 000 routes which is far more than Interior Gateway Protocols IGPs such as EIGRP or OSPF were designed to handle. Additionally whereas private internetworks generally have only a few possible paths with the Internet there could literally be thousands of ways to arrive at the same destination. EIGRP or OSPF would have major problems under these circumstances. Clearly another protocol is needed to deal with the complex routing issues on the public Internet. The answer to this problem is BGP or more precisely BGP 4. Unlike OSPF or EIGRP which were designed to be intra-AS autonomous system BGP was specifically designed to route traffic between autonomous systems and is therefore called an Inter-AS routing protocol. This chapter gives some background on the development of this protocol explains the difference between EBGP and IBGP explores some of the most popular design concepts and discusses more complex issues such as route reflectors and confederations. The History of BGP Border Gateway Protocol 4 BGP 4 was preceded by BGP 1 BGP 2 and BGP 3 as standards for use in exchanging TCP IP routing information between domains. Furthermore all BGP versions were preceded by the Exterior Gateway Protocol EGP as both a standard and a protocol for interdomain routing. The Internet and most of the backbone providers were using EGP exclusively until the mid 1990 was limited use of BGP 3 on any production network primarily because of the stability of EGP and the lack of significant differences in features available in BGP 3. However BGP 4 was developed to .
