IS-IS：Intermediate System to Intermediate System Routing Protocol
IS-IS is a routing protocol proposed by ISO. It is a link state protocol. In this protocol, IS (the router) is CCNP Certification responsible for exchanging routing information based on link overhead and determining network topology. IS-IS is similar to the of TCP/IP network. ISO network includes the terminal system, the inter Open Shortest Path First (OSPF) protocol mediate system, areas and domains. The terminal system refers to user equipment, and the intermediate system refers to the router. A local group formed by routers are called an area, and multiple areas form a domain. IS-IS is designed to provide intra-domain or intra-region routing. IS-IS combines with CLNP, ES-IS and IDRP protocols to provide complete routing for the entire network. check for ccnp cost
IS-IS routing uses a two-layer routing system. Level 1 routers only know the topology in their own area, including all routers and hosts, but do not know the routers and destinations outside the area. Level 1 routers forward all traffic which goes to other areas to an L2 router in this area. This L2 router knows the topology of level 2 and does not need to know any topology of level 1, unless it is also a L1 router in this area. The IS-IS suitable for transmitting IP network information is called integrated IS-IS. Among the current routing protocols, integrated IS-IS has the most important feature: it supports VLSM and fast convergence. In addition, it is scalable and can support large-scale networks.
Cisco’s Internetwork Operating System (IOS) is a complex operating system optimized for Internetworking- similar to a Network Operating System (NOS), such as Novell’s NetWare, which is optimized for LANs. IOS provides unified rules for maintaining an Internet economically and effectively for a long time. In short, it is a software architecture separated from hardware. With the continuous development of network technology, it can be dynamically upgraded to adapt to changing technologies (hardware and software). IOS can be regarded as an Internetworking hub: a highly intelligent administrator responsible for managing and controlling complex distributed network resources.
Interior Gateway Protocol (IGP)
IGP is a protocol dedicated to exchanging data flow channel information between gateways in an autonomous network system (such as an autonomous network system within a local community). Network IP protocol or other network protocols often determine how to transmit data flow through these channel information. At present, the two most commonly used interior gateway protocols are: Routing Information Protocol (RIP) and Open Shortest Path First (OSPF) protocol. At present, IGP includes RIP, OSPF, IGRP, EIGRP, IS-IS and other protocols.
IPv6 is the abbreviation of Internet Protocol version 6. Pv6 is the next generation IP protocol designed by IETF (Internet Engineering Task Force) to replace the current version of IP protocol (IPv4). At present, the protocol family adopted by the global Internet is TCP/IP protocol family. IP is the network layer protocol in TCP/IP protocol family, and is the core protocol of TCP/IP protocol family. The current version number of the IP protocol is 4 (IPv4 for short), and its next version is IPv6. IPv6 is in the process of continuous development and improvement. It will replace IPv4, which is widely used at present, in the near future. Everyone will have more IP addresses.
STP is the abbreviation of Spanning Tree Protocol. CCNP Certification The protocol can be applied to the loop network to achieve path redundancy through a certain algorithm. At the same time, the loop network is pruned into a tree network without loop, so as to avoid the proliferation and infinite circulation of packets in the loop network. The basic principle of STP is to determine the network topology by passing a special protocol message between switches (this protocol message is called “configuration message” in IEEE 802.1D). The configuration message contains enough information to ensure that the switch completes the spanning tree calculation. CCNP Certification The main application of spanning tree protocol is to avoid network loopback in LAN and solve the problem of “broadcast storm” in looped Ethernet network. In a sense, it is a network protection technology, which can eliminate the circular connection caused by errors or accidents.